Commit Graph

840 Commits

Author SHA1 Message Date
Linus Torvalds
63eb28bb14 ARM:
- Host driver for GICv5, the next generation interrupt controller for
   arm64, including support for interrupt routing, MSIs, interrupt
   translation and wired interrupts.
 
 - Use FEAT_GCIE_LEGACY on GICv5 systems to virtualize GICv3 VMs on
   GICv5 hardware, leveraging the legacy VGIC interface.
 
 - Userspace control of the 'nASSGIcap' GICv3 feature, allowing
   userspace to disable support for SGIs w/o an active state on hardware
   that previously advertised it unconditionally.
 
 - Map supporting endpoints with cacheable memory attributes on systems
   with FEAT_S2FWB and DIC where KVM no longer needs to perform cache
   maintenance on the address range.
 
 - Nested support for FEAT_RAS and FEAT_DoubleFault2, allowing the guest
   hypervisor to inject external aborts into an L2 VM and take traps of
   masked external aborts to the hypervisor.
 
 - Convert more system register sanitization to the config-driven
   implementation.
 
 - Fixes to the visibility of EL2 registers, namely making VGICv3 system
   registers accessible through the VGIC device instead of the ONE_REG
   vCPU ioctls.
 
 - Various cleanups and minor fixes.
 
 LoongArch:
 
 - Add stat information for in-kernel irqchip
 
 - Add tracepoints for CPUCFG and CSR emulation exits
 
 - Enhance in-kernel irqchip emulation
 
 - Various cleanups.
 
 RISC-V:
 
 - Enable ring-based dirty memory tracking
 
 - Improve perf kvm stat to report interrupt events
 
 - Delegate illegal instruction trap to VS-mode
 
 - MMU improvements related to upcoming nested virtualization
 
 s390x
 
 - Fixes
 
 x86:
 
 - Add CONFIG_KVM_IOAPIC for x86 to allow disabling support for I/O APIC,
   PIC, and PIT emulation at compile time.
 
 - Share device posted IRQ code between SVM and VMX and
   harden it against bugs and runtime errors.
 
 - Use vcpu_idx, not vcpu_id, for GA log tag/metadata, to make lookups O(1)
   instead of O(n).
 
 - For MMIO stale data mitigation, track whether or not a vCPU has access to
   (host) MMIO based on whether the page tables have MMIO pfns mapped; using
   VFIO is prone to false negatives
 
 - Rework the MSR interception code so that the SVM and VMX APIs are more or
   less identical.
 
 - Recalculate all MSR intercepts from scratch on MSR filter changes,
   instead of maintaining shadow bitmaps.
 
 - Advertise support for LKGS (Load Kernel GS base), a new instruction
   that's loosely related to FRED, but is supported and enumerated
   independently.
 
 - Fix a user-triggerable WARN that syzkaller found by setting the vCPU
   in INIT_RECEIVED state (aka wait-for-SIPI), and then putting the vCPU
   into VMX Root Mode (post-VMXON).  Trying to detect every possible path
   leading to architecturally forbidden states is hard and even risks
   breaking userspace (if it goes from valid to valid state but passes
   through invalid states), so just wait until KVM_RUN to detect that
   the vCPU state isn't allowed.
 
 - Add KVM_X86_DISABLE_EXITS_APERFMPERF to allow disabling interception of
   APERF/MPERF reads, so that a "properly" configured VM can access
   APERF/MPERF.  This has many caveats (APERF/MPERF cannot be zeroed
   on vCPU creation or saved/restored on suspend and resume, or preserved
   over thread migration let alone VM migration) but can be useful whenever
   you're interested in letting Linux guests see the effective physical CPU
   frequency in /proc/cpuinfo.
 
 - Reject KVM_SET_TSC_KHZ for vm file descriptors if vCPUs have been
   created, as there's no known use case for changing the default
   frequency for other VM types and it goes counter to the very reason
   why the ioctl was added to the vm file descriptor.  And also, there
   would be no way to make it work for confidential VMs with a "secure"
   TSC, so kill two birds with one stone.
 
 - Dynamically allocation the shadow MMU's hashed page list, and defer
   allocating the hashed list until it's actually needed (the TDP MMU
   doesn't use the list).
 
 - Extract many of KVM's helpers for accessing architectural local APIC
   state to common x86 so that they can be shared by guest-side code for
   Secure AVIC.
 
 - Various cleanups and fixes.
 
 x86 (Intel):
 
 - Preserve the host's DEBUGCTL.FREEZE_IN_SMM when running the guest.
   Failure to honor FREEZE_IN_SMM can leak host state into guests.
 
 - Explicitly check vmcs12.GUEST_DEBUGCTL on nested VM-Enter to prevent
   L1 from running L2 with features that KVM doesn't support, e.g. BTF.
 
 x86 (AMD):
 
 - WARN and reject loading kvm-amd.ko instead of panicking the kernel if the
   nested SVM MSRPM offsets tracker can't handle an MSR (which is pretty
   much a static condition and therefore should never happen, but still).
 
 - Fix a variety of flaws and bugs in the AVIC device posted IRQ code.
 
 - Inhibit AVIC if a vCPU's ID is too big (relative to what hardware
   supports) instead of rejecting vCPU creation.
 
 - Extend enable_ipiv module param support to SVM, by simply leaving
   IsRunning clear in the vCPU's physical ID table entry.
 
 - Disable IPI virtualization, via enable_ipiv, if the CPU is affected by
   erratum #1235, to allow (safely) enabling AVIC on such CPUs.
 
 - Request GA Log interrupts if and only if the target vCPU is blocking,
   i.e. only if KVM needs a notification in order to wake the vCPU.
 
 - Intercept SPEC_CTRL on AMD if the MSR shouldn't exist according to the
   vCPU's CPUID model.
 
 - Accept any SNP policy that is accepted by the firmware with respect to
   SMT and single-socket restrictions.  An incompatible policy doesn't put
   the kernel at risk in any way, so there's no reason for KVM to care.
 
 - Drop a superfluous WBINVD (on all CPUs!) when destroying a VM and
   use WBNOINVD instead of WBINVD when possible for SEV cache maintenance.
 
 - When reclaiming memory from an SEV guest, only do cache flushes on CPUs
   that have ever run a vCPU for the guest, i.e. don't flush the caches for
   CPUs that can't possibly have cache lines with dirty, encrypted data.
 
 Generic:
 
 - Rework irqbypass to track/match producers and consumers via an xarray
   instead of a linked list.  Using a linked list leads to O(n^2) insertion
   times, which is hugely problematic for use cases that create large
   numbers of VMs.  Such use cases typically don't actually use irqbypass,
   but eliminating the pointless registration is a future problem to
   solve as it likely requires new uAPI.
 
 - Track irqbypass's "token" as "struct eventfd_ctx *" instead of a "void *",
   to avoid making a simple concept unnecessarily difficult to understand.
 
 - Decouple device posted IRQs from VFIO device assignment, as binding a VM
   to a VFIO group is not a requirement for enabling device posted IRQs.
 
 - Clean up and document/comment the irqfd assignment code.
 
 - Disallow binding multiple irqfds to an eventfd with a priority waiter,
   i.e.  ensure an eventfd is bound to at most one irqfd through the entire
   host, and add a selftest to verify eventfd:irqfd bindings are globally
   unique.
 
 - Add a tracepoint for KVM_SET_MEMORY_ATTRIBUTES to help debug issues
   related to private <=> shared memory conversions.
 
 - Drop guest_memfd's .getattr() implementation as the VFS layer will call
   generic_fillattr() if inode_operations.getattr is NULL.
 
 - Fix issues with dirty ring harvesting where KVM doesn't bound the
   processing of entries in any way, which allows userspace to keep KVM
   in a tight loop indefinitely.
 
 - Kill off kvm_arch_{start,end}_assignment() and x86's associated tracking,
   now that KVM no longer uses assigned_device_count as a heuristic for
   either irqbypass usage or MDS mitigation.
 
 Selftests:
 
 - Fix a comment typo.
 
 - Verify KVM is loaded when getting any KVM module param so that attempting
   to run a selftest without kvm.ko loaded results in a SKIP message about
   KVM not being loaded/enabled (versus some random parameter not existing).
 
 - Skip tests that hit EACCES when attempting to access a file, and rpint
   a "Root required?" help message.  In most cases, the test just needs to
   be run with elevated permissions.
 -----BEGIN PGP SIGNATURE-----
 
 iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmiKXMgUHHBib256aW5p
 QHJlZGhhdC5jb20ACgkQv/vSX3jHroMhMQf/QDhC/CP1aGXph2whuyeD2NMqPKiU
 9KdnDNST+ftPwjg9QxZ9mTaa8zeVz/wly6XlxD9OQHy+opM1wcys3k0GZAFFEEQm
 YrThgURdzEZ3nwJZgb+m0t4wjJQtpiFIBwAf7qq6z1VrqQBEmHXJ/8QxGuqO+BNC
 j5q/X+q6KZwehKI6lgFBrrOKWFaxqhnRAYfW6rGBxRXxzTJuna37fvDpodQnNceN
 zOiq+avfriUMArTXTqOteJNKU0229HjiPSnjILLnFQ+B3akBlwNG0jk7TMaAKR6q
 IZWG1EIS9q1BAkGXaw6DE1y6d/YwtXCR5qgAIkiGwaPt5yj9Oj6kRN2Ytw==
 =j2At
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "ARM:

   - Host driver for GICv5, the next generation interrupt controller for
     arm64, including support for interrupt routing, MSIs, interrupt
     translation and wired interrupts

   - Use FEAT_GCIE_LEGACY on GICv5 systems to virtualize GICv3 VMs on
     GICv5 hardware, leveraging the legacy VGIC interface

   - Userspace control of the 'nASSGIcap' GICv3 feature, allowing
     userspace to disable support for SGIs w/o an active state on
     hardware that previously advertised it unconditionally

   - Map supporting endpoints with cacheable memory attributes on
     systems with FEAT_S2FWB and DIC where KVM no longer needs to
     perform cache maintenance on the address range

   - Nested support for FEAT_RAS and FEAT_DoubleFault2, allowing the
     guest hypervisor to inject external aborts into an L2 VM and take
     traps of masked external aborts to the hypervisor

   - Convert more system register sanitization to the config-driven
     implementation

   - Fixes to the visibility of EL2 registers, namely making VGICv3
     system registers accessible through the VGIC device instead of the
     ONE_REG vCPU ioctls

   - Various cleanups and minor fixes

  LoongArch:

   - Add stat information for in-kernel irqchip

   - Add tracepoints for CPUCFG and CSR emulation exits

   - Enhance in-kernel irqchip emulation

   - Various cleanups

  RISC-V:

   - Enable ring-based dirty memory tracking

   - Improve perf kvm stat to report interrupt events

   - Delegate illegal instruction trap to VS-mode

   - MMU improvements related to upcoming nested virtualization

  s390x

   - Fixes

  x86:

   - Add CONFIG_KVM_IOAPIC for x86 to allow disabling support for I/O
     APIC, PIC, and PIT emulation at compile time

   - Share device posted IRQ code between SVM and VMX and harden it
     against bugs and runtime errors

   - Use vcpu_idx, not vcpu_id, for GA log tag/metadata, to make lookups
     O(1) instead of O(n)

   - For MMIO stale data mitigation, track whether or not a vCPU has
     access to (host) MMIO based on whether the page tables have MMIO
     pfns mapped; using VFIO is prone to false negatives

   - Rework the MSR interception code so that the SVM and VMX APIs are
     more or less identical

   - Recalculate all MSR intercepts from scratch on MSR filter changes,
     instead of maintaining shadow bitmaps

   - Advertise support for LKGS (Load Kernel GS base), a new instruction
     that's loosely related to FRED, but is supported and enumerated
     independently

   - Fix a user-triggerable WARN that syzkaller found by setting the
     vCPU in INIT_RECEIVED state (aka wait-for-SIPI), and then putting
     the vCPU into VMX Root Mode (post-VMXON). Trying to detect every
     possible path leading to architecturally forbidden states is hard
     and even risks breaking userspace (if it goes from valid to valid
     state but passes through invalid states), so just wait until
     KVM_RUN to detect that the vCPU state isn't allowed

   - Add KVM_X86_DISABLE_EXITS_APERFMPERF to allow disabling
     interception of APERF/MPERF reads, so that a "properly" configured
     VM can access APERF/MPERF. This has many caveats (APERF/MPERF
     cannot be zeroed on vCPU creation or saved/restored on suspend and
     resume, or preserved over thread migration let alone VM migration)
     but can be useful whenever you're interested in letting Linux
     guests see the effective physical CPU frequency in /proc/cpuinfo

   - Reject KVM_SET_TSC_KHZ for vm file descriptors if vCPUs have been
     created, as there's no known use case for changing the default
     frequency for other VM types and it goes counter to the very reason
     why the ioctl was added to the vm file descriptor. And also, there
     would be no way to make it work for confidential VMs with a
     "secure" TSC, so kill two birds with one stone

   - Dynamically allocation the shadow MMU's hashed page list, and defer
     allocating the hashed list until it's actually needed (the TDP MMU
     doesn't use the list)

   - Extract many of KVM's helpers for accessing architectural local
     APIC state to common x86 so that they can be shared by guest-side
     code for Secure AVIC

   - Various cleanups and fixes

  x86 (Intel):

   - Preserve the host's DEBUGCTL.FREEZE_IN_SMM when running the guest.
     Failure to honor FREEZE_IN_SMM can leak host state into guests

   - Explicitly check vmcs12.GUEST_DEBUGCTL on nested VM-Enter to
     prevent L1 from running L2 with features that KVM doesn't support,
     e.g. BTF

  x86 (AMD):

   - WARN and reject loading kvm-amd.ko instead of panicking the kernel
     if the nested SVM MSRPM offsets tracker can't handle an MSR (which
     is pretty much a static condition and therefore should never
     happen, but still)

   - Fix a variety of flaws and bugs in the AVIC device posted IRQ code

   - Inhibit AVIC if a vCPU's ID is too big (relative to what hardware
     supports) instead of rejecting vCPU creation

   - Extend enable_ipiv module param support to SVM, by simply leaving
     IsRunning clear in the vCPU's physical ID table entry

   - Disable IPI virtualization, via enable_ipiv, if the CPU is affected
     by erratum #1235, to allow (safely) enabling AVIC on such CPUs

   - Request GA Log interrupts if and only if the target vCPU is
     blocking, i.e. only if KVM needs a notification in order to wake
     the vCPU

   - Intercept SPEC_CTRL on AMD if the MSR shouldn't exist according to
     the vCPU's CPUID model

   - Accept any SNP policy that is accepted by the firmware with respect
     to SMT and single-socket restrictions. An incompatible policy
     doesn't put the kernel at risk in any way, so there's no reason for
     KVM to care

   - Drop a superfluous WBINVD (on all CPUs!) when destroying a VM and
     use WBNOINVD instead of WBINVD when possible for SEV cache
     maintenance

   - When reclaiming memory from an SEV guest, only do cache flushes on
     CPUs that have ever run a vCPU for the guest, i.e. don't flush the
     caches for CPUs that can't possibly have cache lines with dirty,
     encrypted data

  Generic:

   - Rework irqbypass to track/match producers and consumers via an
     xarray instead of a linked list. Using a linked list leads to
     O(n^2) insertion times, which is hugely problematic for use cases
     that create large numbers of VMs. Such use cases typically don't
     actually use irqbypass, but eliminating the pointless registration
     is a future problem to solve as it likely requires new uAPI

   - Track irqbypass's "token" as "struct eventfd_ctx *" instead of a
     "void *", to avoid making a simple concept unnecessarily difficult
     to understand

   - Decouple device posted IRQs from VFIO device assignment, as binding
     a VM to a VFIO group is not a requirement for enabling device
     posted IRQs

   - Clean up and document/comment the irqfd assignment code

   - Disallow binding multiple irqfds to an eventfd with a priority
     waiter, i.e. ensure an eventfd is bound to at most one irqfd
     through the entire host, and add a selftest to verify eventfd:irqfd
     bindings are globally unique

   - Add a tracepoint for KVM_SET_MEMORY_ATTRIBUTES to help debug issues
     related to private <=> shared memory conversions

   - Drop guest_memfd's .getattr() implementation as the VFS layer will
     call generic_fillattr() if inode_operations.getattr is NULL

   - Fix issues with dirty ring harvesting where KVM doesn't bound the
     processing of entries in any way, which allows userspace to keep
     KVM in a tight loop indefinitely

   - Kill off kvm_arch_{start,end}_assignment() and x86's associated
     tracking, now that KVM no longer uses assigned_device_count as a
     heuristic for either irqbypass usage or MDS mitigation

  Selftests:

   - Fix a comment typo

   - Verify KVM is loaded when getting any KVM module param so that
     attempting to run a selftest without kvm.ko loaded results in a
     SKIP message about KVM not being loaded/enabled (versus some random
     parameter not existing)

   - Skip tests that hit EACCES when attempting to access a file, and
     print a "Root required?" help message. In most cases, the test just
     needs to be run with elevated permissions"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (340 commits)
  Documentation: KVM: Use unordered list for pre-init VGIC registers
  RISC-V: KVM: Avoid re-acquiring memslot in kvm_riscv_gstage_map()
  RISC-V: KVM: Use find_vma_intersection() to search for intersecting VMAs
  RISC-V: perf/kvm: Add reporting of interrupt events
  RISC-V: KVM: Enable ring-based dirty memory tracking
  RISC-V: KVM: Fix inclusion of Smnpm in the guest ISA bitmap
  RISC-V: KVM: Delegate illegal instruction fault to VS mode
  RISC-V: KVM: Pass VMID as parameter to kvm_riscv_hfence_xyz() APIs
  RISC-V: KVM: Factor-out g-stage page table management
  RISC-V: KVM: Add vmid field to struct kvm_riscv_hfence
  RISC-V: KVM: Introduce struct kvm_gstage_mapping
  RISC-V: KVM: Factor-out MMU related declarations into separate headers
  RISC-V: KVM: Use ncsr_xyz() in kvm_riscv_vcpu_trap_redirect()
  RISC-V: KVM: Implement kvm_arch_flush_remote_tlbs_range()
  RISC-V: KVM: Don't flush TLB when PTE is unchanged
  RISC-V: KVM: Replace KVM_REQ_HFENCE_GVMA_VMID_ALL with KVM_REQ_TLB_FLUSH
  RISC-V: KVM: Rename and move kvm_riscv_local_tlb_sanitize()
  RISC-V: KVM: Drop the return value of kvm_riscv_vcpu_aia_init()
  RISC-V: KVM: Check kvm_riscv_vcpu_alloc_vector_context() return value
  KVM: arm64: selftests: Add FEAT_RAS EL2 registers to get-reg-list
  ...
2025-07-30 17:14:01 -07:00
Mark Rutland
57d88f02eb KVM: s390: Rework guest entry logic
In __vcpu_run() and do_vsie_run(), we enter an RCU extended quiescent
state (EQS) by calling guest_enter_irqoff(), which lasts until
__vcpu_run() calls guest_exit_irqoff(). However, between the two we
enable interrupts and may handle interrupts during the EQS. As the IRQ
entry code will not wake RCU in this case, we may run the core IRQ code
and IRQ handler without RCU watching, leading to various potential
problems.

It is necessary to unmask (host) interrupts around entering the guest,
as entering the guest via SIE will not automatically unmask these. When
a host interrupt is taken from a guest, it is taken via its regular
host IRQ handler rather than being treated as a direct exit from SIE.
Due to this, we cannot simply mask interrupts around guest entry, and
must handle interrupts during this window, waking RCU as required.

Additionally, between guest_enter_irqoff() and guest_exit_irqoff(), we
use local_irq_enable() and local_irq_disable() to unmask interrupts,
violating the ordering requirements for RCU/lockdep/tracing around
entry/exit sequences. Further, since this occurs in an instrumentable
function, it's possible that instrumented code runs during this window,
with potential usage of RCU, etc.

To fix the RCU wakeup problem, an s390 implementation of
arch_in_rcu_eqs() is added which checks for PF_VCPU in current->flags.
PF_VCPU is set/cleared by guest_timing_{enter,exit}_irqoff(), which
surround the actual guest entry.

To fix the remaining issues, the lower-level guest entry logic is moved
into a shared noinstr helper function using the
guest_state_{enter,exit}_irqoff() helpers. These perform all the
lockdep/RCU/tracing manipulation necessary, but as sie64a() does not
enable/disable interrupts, we must do this explicitly with the
non-instrumented arch_local_irq_{enable,disable}() helpers:

        guest_state_enter_irqoff()

        arch_local_irq_enable();
        sie64a(...);
        arch_local_irq_disable();

        guest_state_exit_irqoff();

[ajd@linux.ibm.com: rebase, fix commit message]

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20250708092742.104309-3-ajd@linux.ibm.com
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Message-ID: <20250708092742.104309-3-ajd@linux.ibm.com>
2025-07-21 13:01:03 +00:00
Heiko Carstens
65c9a9f925 s390: Explicitly include <linux/export.h>
Explicitly include <linux/export.h> in files which contain an
EXPORT_SYMBOL().

See commit a934a57a42 ("scripts/misc-check: check missing #include
<linux/export.h> when W=1") for more details.

Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2025-06-17 18:18:02 +02:00
Claudio Imbrenda
d6c8097803 KVM: s390: Simplify and move pv code
All functions in kvm/gmap.c fit better in kvm/pv.c instead.
Move and rename them appropriately, then delete the now empty
kvm/gmap.c and kvm/gmap.h.

Reviewed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20250528095502.226213-5-imbrenda@linux.ibm.com
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20250528095502.226213-5-imbrenda@linux.ibm.com>
2025-05-28 17:48:04 +02:00
Claudio Imbrenda
200197908d KVM: s390: Refactor and split some gmap helpers
Refactor some gmap functions; move the implementation into a separate
file with only helper functions. The new helper functions work on vm
addresses, leaving all gmap logic in the gmap functions, which mostly
become just wrappers.

The whole gmap handling is going to be moved inside KVM soon, but the
helper functions need to touch core mm functions, and thus need to
stay in the core of kernel.

Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20250528095502.226213-4-imbrenda@linux.ibm.com
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20250528095502.226213-4-imbrenda@linux.ibm.com>
2025-05-28 17:48:04 +02:00
Linus Torvalds
0e8863244e ARM:
* Rework heuristics for resolving the fault IPA (HPFAR_EL2 v. re-walk
   stage-1 page tables) to align with the architecture. This avoids
   possibly taking an SEA at EL2 on the page table walk or using an
   architecturally UNKNOWN fault IPA.
 
 * Use acquire/release semantics in the KVM FF-A proxy to avoid reading
   a stale value for the FF-A version.
 
 * Fix KVM guest driver to match PV CPUID hypercall ABI.
 
 * Use Inner Shareable Normal Write-Back mappings at stage-1 in KVM
   selftests, which is the only memory type for which atomic
   instructions are architecturally guaranteed to work.
 
 s390:
 
 * Don't use %pK for debug printing and tracepoints.
 
 x86:
 
 * Use a separate subclass when acquiring KVM's per-CPU posted interrupts
   wakeup lock in the scheduled out path, i.e. when adding a vCPU on
   the list of vCPUs to wake, to workaround a false positive deadlock.
   The schedule out code runs with a scheduler lock that the wakeup
   handler takes in the opposite order; but it does so with IRQs disabled
   and cannot run concurrently with a wakeup.
 
 * Explicitly zero-initialize on-stack CPUID unions
 
 * Allow building irqbypass.ko as as module when kvm.ko is a module
 
 * Wrap relatively expensive sanity check with KVM_PROVE_MMU
 
 * Acquire SRCU in KVM_GET_MP_STATE to protect guest memory accesses
 
 selftests:
 
 * Add more scenarios to the MONITOR/MWAIT test.
 
 * Add option to rseq test to override /dev/cpu_dma_latency
 
 * Bring list of exit reasons up to date
 
 * Cleanup Makefile to list once tests that are valid on all architectures
 
 Other:
 
 * Documentation fixes
 -----BEGIN PGP SIGNATURE-----
 
 iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmf083IUHHBib256aW5p
 QHJlZGhhdC5jb20ACgkQv/vSX3jHroN1dgf/QwfpZcHoMNQSnrc1jMy2LHrArln2
 XfmsOGZTU7kyoLQsLWGAPNocOveGdiemTDsj5ZXoNMnqV8hCBr+tZuv2gWI1rr/o
 kiGerdIgSZ9piTjBlJkVAaOzbWhg2DUnr7qVVzEzFY9+rPNyQ81vgAfU7h56KhYB
 optecozmBrHHAxvQZwmPeL9UyPWFjOF1BY/8LTMx7X+aVuCX6qx1JqO3a3ylAw4J
 tGXv6qFJfuCnu1d1b4X0ILce0iMUTOjQzvTcIm+BKjYycecl+3j1aczC/BOorIgc
 mf0+XeauhcTduK73pirnvx2b05eOxntgkOpwJytO2RP6pE0uK+2Th/C3Qg==
 =ba/Y
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:
 "ARM:

   - Rework heuristics for resolving the fault IPA (HPFAR_EL2 v. re-walk
     stage-1 page tables) to align with the architecture. This avoids
     possibly taking an SEA at EL2 on the page table walk or using an
     architecturally UNKNOWN fault IPA

   - Use acquire/release semantics in the KVM FF-A proxy to avoid
     reading a stale value for the FF-A version

   - Fix KVM guest driver to match PV CPUID hypercall ABI

   - Use Inner Shareable Normal Write-Back mappings at stage-1 in KVM
     selftests, which is the only memory type for which atomic
     instructions are architecturally guaranteed to work

  s390:

   - Don't use %pK for debug printing and tracepoints

  x86:

   - Use a separate subclass when acquiring KVM's per-CPU posted
     interrupts wakeup lock in the scheduled out path, i.e. when adding
     a vCPU on the list of vCPUs to wake, to workaround a false positive
     deadlock. The schedule out code runs with a scheduler lock that the
     wakeup handler takes in the opposite order; but it does so with
     IRQs disabled and cannot run concurrently with a wakeup

   - Explicitly zero-initialize on-stack CPUID unions

   - Allow building irqbypass.ko as as module when kvm.ko is a module

   - Wrap relatively expensive sanity check with KVM_PROVE_MMU

   - Acquire SRCU in KVM_GET_MP_STATE to protect guest memory accesses

  selftests:

   - Add more scenarios to the MONITOR/MWAIT test

   - Add option to rseq test to override /dev/cpu_dma_latency

   - Bring list of exit reasons up to date

   - Cleanup Makefile to list once tests that are valid on all
     architectures

  Other:

   - Documentation fixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (26 commits)
  KVM: arm64: Use acquire/release to communicate FF-A version negotiation
  KVM: arm64: selftests: Explicitly set the page attrs to Inner-Shareable
  KVM: arm64: selftests: Introduce and use hardware-definition macros
  KVM: VMX: Use separate subclasses for PI wakeup lock to squash false positive
  KVM: VMX: Assert that IRQs are disabled when putting vCPU on PI wakeup list
  KVM: x86: Explicitly zero-initialize on-stack CPUID unions
  KVM: Allow building irqbypass.ko as as module when kvm.ko is a module
  KVM: x86/mmu: Wrap sanity check on number of TDP MMU pages with KVM_PROVE_MMU
  KVM: selftests: Add option to rseq test to override /dev/cpu_dma_latency
  KVM: x86: Acquire SRCU in KVM_GET_MP_STATE to protect guest memory accesses
  Documentation: kvm: remove KVM_CAP_MIPS_TE
  Documentation: kvm: organize capabilities in the right section
  Documentation: kvm: fix some definition lists
  Documentation: kvm: drop "Capability" heading from capabilities
  Documentation: kvm: give correct name for KVM_CAP_SPAPR_MULTITCE
  Documentation: KVM: KVM_GET_SUPPORTED_CPUID now exposes TSC_DEADLINE
  selftests: kvm: list once tests that are valid on all architectures
  selftests: kvm: bring list of exit reasons up to date
  selftests: kvm: revamp MONITOR/MWAIT tests
  KVM: arm64: Don't translate FAR if invalid/unsafe
  ...
2025-04-08 13:47:55 -07:00
Paolo Bonzini
adb9061ecc Pointer print format fixes
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEwGNS88vfc9+v45Yq41TmuOI4ufgFAmfemSMACgkQ41TmuOI4
 ufjJSBAAyt4Y12hnen1IkMTpcmn4l1bvLKQ7NXOXuapLXeHJc0BvZ8okbEdNs7uo
 YUlRlOfSNvL2kAYJUaieQcNXoUxQqX/Yb+dsKcXuKIaWaxVvd4U4wLvWWe4y/9MS
 xp9/CjIKw17OmXLBCg0yi5hh3fFcSdPHedtcq2E/x4RaPWgxwnr+olPrwkakbum3
 OQE3azqvSRSMIvT24NsPki91lhJiyc+blqXb+SB68jkvbvtI4i/ESPzw1yYpmZEp
 2587kFdc3RXoFB0bW+2l8DVm+sxV6E+F3a/bDSjXcE5CHLT3RWYhfF1UI+fM5XrL
 aBpaCOSVcMu9L21uJeo2d1VMa3oROCGl5cbYwGsRPnLrL64QbphtDOkQ775E59+u
 ztk9S3UKgY9oaCePidnlsrjPS4tyqvj25jzdoC/nbHuW6fzRv67S+xhWEgIdvjf/
 n+nR9SZCIEzhYzHA5tyt+lTyCIw+vZbdOxzXor5klx8gfaY/hjRBY5ebcvq3P4ha
 umjNPhtZ/Gy6kWhPHcRXY//mBGkhkLwc/BvfotxCcFuMqZcpadBKbRT3NQ8r3JWA
 LA8VJC0z5YJh3PzzNPyiJINTYbgr3n7GF7+xWnOXpcVm6dGlNOOEpaMUd3zdCJl7
 D3Qdpux5/qfOd0MRgOFY3FHvS92ykf+yvT7V+Vcb287CLpdCuiY=
 =rF37
 -----END PGP SIGNATURE-----

Merge tag 'kvm-s390-next-6.15-1' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

Pointer print format fixes
2025-03-31 06:08:11 -04:00
Linus Torvalds
f90f2145b2 s390 updates for 6.15 merge window
- Add sorting of mcount locations at build time
 
 - Rework uaccess functions with C exception handling to shorten inline
   assembly size and enable full inlining. This yields near-optimal code
   for small constant copies with a ~40kb kernel size increase
 
 - Add support for a configurable STRICT_MM_TYPECHECKS which allows to
   generate better code, but also allows to have type checking for
   debug builds
 
 - Optimize get_lowcore() for common callers with alternatives that
   nearly revert to the pre-relocated lowcore code, while also slightly
   reducing syscall entry and exit time
 
 - Convert MACHINE_HAS_* checks for single facility tests into cpu_has_*
   style macros that call test_facility(), and for features with additional
   conditions, add a new ALT_TYPE_FEATURE alternative to provide a static
   branch via alternative patching. Also, move machine feature detection
   to the decompressor for early patching and add debugging functionality
   to easily show which alternatives are patched
 
 - Add exception table support to early boot / startup code to get rid
   of the open coded exception handling
 
 - Use asm_inline for all inline assemblies with EX_TABLE or ALTERNATIVE
   to ensure correct inlining and unrolling decisions
 
 - Remove 2k page table leftovers now that s390 has been switched to
   always allocate 4k page tables
 
 - Split kfence pool into 4k mappings in arch_kfence_init_pool() and
   remove the architecture-specific kfence_split_mapping()
 
 - Use READ_ONCE_NOCHECK() in regs_get_kernel_stack_nth() to silence
   spurious KASAN warnings from opportunistic ftrace argument tracing
 
 - Force __atomic_add_const() variants on s390 to always return void,
   ensuring compile errors for improper usage
 
 - Remove s390's ioremap_wt() and pgprot_writethrough() due to mismatched
   semantics and lack of known users, relying on asm-generic fallbacks
 
 - Signal eventfd in vfio-ap to notify userspace when the guest AP
   configuration changes, including during mdev removal
 
 - Convert mdev_types from an array to a pointer in vfio-ccw and vfio-ap
   drivers to avoid fake flex array confusion
 
 - Cleanup trap code
 
 - Remove references to the outdated linux390@de.ibm.com address
 
 - Other various small fixes and improvements all over the code
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCAAdFiEE3QHqV+H2a8xAv27vjYWKoQLXFBgFAmfmuPwACgkQjYWKoQLX
 FBgTDAgAjKmZ5OYjACRfYepTvKk9SDqa2CBlQZ+BhbAXEVIrxKnv8OkImAXoWNsM
 mFxiCxAHWdcD+nqTrxFsXhkNLsndijlwnj/IqZgvy6R/3yNtBlAYRPLujOmVrsQB
 dWB8Dl38p63Ip1JfAqyabiAOUjfhrclRcM5FX5tgciXA6N/vhY3OM6k0+k7wN4Nj
 Dei/rCrnYRXTrFQgtM4w8JTIrwdnXjeKvaTYCflh4Q5ISJ7TceSF7cqq8HOs5hhK
 o2ciaoTdx212522CIsxeN3Ls3jrn8bCOCoOeSCysc5RL84grAuFnmjSajo1LFide
 S/TQtHXYy78Wuei9xvHi561ogiv/ww==
 =Kxgc
 -----END PGP SIGNATURE-----

Merge tag 's390-6.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Add sorting of mcount locations at build time

 - Rework uaccess functions with C exception handling to shorten inline
   assembly size and enable full inlining. This yields near-optimal code
   for small constant copies with a ~40kb kernel size increase

 - Add support for a configurable STRICT_MM_TYPECHECKS which allows to
   generate better code, but also allows to have type checking for debug
   builds

 - Optimize get_lowcore() for common callers with alternatives that
   nearly revert to the pre-relocated lowcore code, while also slightly
   reducing syscall entry and exit time

 - Convert MACHINE_HAS_* checks for single facility tests into cpu_has_*
   style macros that call test_facility(), and for features with
   additional conditions, add a new ALT_TYPE_FEATURE alternative to
   provide a static branch via alternative patching. Also, move machine
   feature detection to the decompressor for early patching and add
   debugging functionality to easily show which alternatives are patched

 - Add exception table support to early boot / startup code to get rid
   of the open coded exception handling

 - Use asm_inline for all inline assemblies with EX_TABLE or ALTERNATIVE
   to ensure correct inlining and unrolling decisions

 - Remove 2k page table leftovers now that s390 has been switched to
   always allocate 4k page tables

 - Split kfence pool into 4k mappings in arch_kfence_init_pool() and
   remove the architecture-specific kfence_split_mapping()

 - Use READ_ONCE_NOCHECK() in regs_get_kernel_stack_nth() to silence
   spurious KASAN warnings from opportunistic ftrace argument tracing

 - Force __atomic_add_const() variants on s390 to always return void,
   ensuring compile errors for improper usage

 - Remove s390's ioremap_wt() and pgprot_writethrough() due to
   mismatched semantics and lack of known users, relying on asm-generic
   fallbacks

 - Signal eventfd in vfio-ap to notify userspace when the guest AP
   configuration changes, including during mdev removal

 - Convert mdev_types from an array to a pointer in vfio-ccw and vfio-ap
   drivers to avoid fake flex array confusion

 - Cleanup trap code

 - Remove references to the outdated linux390@de.ibm.com address

 - Other various small fixes and improvements all over the code

* tag 's390-6.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (78 commits)
  s390: Use inline qualifier for all EX_TABLE and ALTERNATIVE inline assemblies
  s390/kfence: Split kfence pool into 4k mappings in arch_kfence_init_pool()
  s390/ptrace: Avoid KASAN false positives in regs_get_kernel_stack_nth()
  s390/boot: Ignore vmlinux.map
  s390/sysctl: Remove "vm/allocate_pgste" sysctl
  s390: Remove 2k vs 4k page table leftovers
  s390/tlb: Use mm_has_pgste() instead of mm_alloc_pgste()
  s390/lowcore: Use lghi instead llilh to clear register
  s390/syscall: Merge __do_syscall() and do_syscall()
  s390/spinlock: Implement SPINLOCK_LOCKVAL with inline assembly
  s390/smp: Implement raw_smp_processor_id() with inline assembly
  s390/current: Implement current with inline assembly
  s390/lowcore: Use inline qualifier for get_lowcore() inline assembly
  s390: Move s390 sysctls into their own file under arch/s390
  s390/syscall: Simplify syscall_get_arguments()
  s390/vfio-ap: Notify userspace that guest's AP config changed when mdev removed
  s390: Remove ioremap_wt() and pgprot_writethrough()
  s390/mm: Add configurable STRICT_MM_TYPECHECKS
  s390/mm: Convert pgste_val() into function
  s390/mm: Convert pgprot_val() into function
  ...
2025-03-29 11:59:43 -07:00
Linus Torvalds
a50b4fe095 A treewide hrtimer timer cleanup
hrtimers are initialized with hrtimer_init() and a subsequent store to
   the callback pointer. This turned out to be suboptimal for the upcoming
   Rust integration and is obviously a silly implementation to begin with.
 
   This cleanup replaces the hrtimer_init(T); T->function = cb; sequence
   with hrtimer_setup(T, cb);
 
   The conversion was done with Coccinelle and a few manual fixups.
 
   Once the conversion has completely landed in mainline, hrtimer_init()
   will be removed and the hrtimer::function becomes a private member.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmff5jQTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoVvRD/wKtuwmiA66NJFgXC0qVq82A6fO3bY8
 GBdbfysDJIbqGu5PTcULTbJ8qkqv3jeLUv6CcXvS4sZ7y/uJQl2lzf8yrD/0bbwc
 rLI6sHiPSZmK93kNVN4X5H7kvt7cE/DYC9nnEOgK3BY5FgKc4n9887d4aVBhL8Lv
 ODwVXvZ+xi351YCj7qRyPU24zt/p4tkkT1o2k4a0HBluqLI0D+V20fke9IERUL8r
 d1uWKlcn0TqYDesE8HXKIhbst3gx52rMJrXBJDHwFmG6v8Pj1fkTXCVpPo8QcBz8
 OTVkpomN9f/Tx4+GZwhZOF86LhLL3OhxD6pT7JhFCXdmSGv+Ez8uyk1YZysM/XpV
 Juy/1yAcBpDIDkmhMFGdAAn48Nn9Fotty0r4je60zSEp1d/4QMXcFme29qr2JTUE
 iWnQ/HD6DxUjVHqy7CYvvo26Xegg1C7qgyOVt4PYZwAM1VKF5P3kzYTb4SAdxtop
 Tpji1sfW9QV08jqMNo6XntD32DSP9S2HqjO9LwBw700jnx2jjJ35fcJs6iodMOUn
 gckIZLMn3L0OoglPdyA5O7SNTbKE7aFiRKdnT/cJtR3Fa39Qu27CwC5gfiyuie9I
 Q+LG8GLuYSBHXAR+PBK4GWlzJ7Dn8k3eqmbnLeKpRMsU6ZzcttgA64xhaviN2wN0
 iJbvLJeisXr3GA==
 =bYAX
 -----END PGP SIGNATURE-----

Merge tag 'timers-cleanups-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer cleanups from Thomas Gleixner:
 "A treewide hrtimer timer cleanup

  hrtimers are initialized with hrtimer_init() and a subsequent store to
  the callback pointer. This turned out to be suboptimal for the
  upcoming Rust integration and is obviously a silly implementation to
  begin with.

  This cleanup replaces the hrtimer_init(T); T->function = cb; sequence
  with hrtimer_setup(T, cb);

  The conversion was done with Coccinelle and a few manual fixups.

  Once the conversion has completely landed in mainline, hrtimer_init()
  will be removed and the hrtimer::function becomes a private member"

* tag 'timers-cleanups-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (100 commits)
  wifi: rt2x00: Switch to use hrtimer_update_function()
  io_uring: Use helper function hrtimer_update_function()
  serial: xilinx_uartps: Use helper function hrtimer_update_function()
  ASoC: fsl: imx-pcm-fiq: Switch to use hrtimer_setup()
  RDMA: Switch to use hrtimer_setup()
  virtio: mem: Switch to use hrtimer_setup()
  drm/vmwgfx: Switch to use hrtimer_setup()
  drm/xe/oa: Switch to use hrtimer_setup()
  drm/vkms: Switch to use hrtimer_setup()
  drm/msm: Switch to use hrtimer_setup()
  drm/i915/request: Switch to use hrtimer_setup()
  drm/i915/uncore: Switch to use hrtimer_setup()
  drm/i915/pmu: Switch to use hrtimer_setup()
  drm/i915/perf: Switch to use hrtimer_setup()
  drm/i915/gvt: Switch to use hrtimer_setup()
  drm/i915/huc: Switch to use hrtimer_setup()
  drm/amdgpu: Switch to use hrtimer_setup()
  stm class: heartbeat: Switch to use hrtimer_setup()
  i2c: Switch to use hrtimer_setup()
  iio: Switch to use hrtimer_setup()
  ...
2025-03-25 10:54:15 -07:00
Thomas Weißschuh
0c7fbae5bc KVM: s390: Don't use %pK through debug printing
Restricted pointers ("%pK") are only meant to be used when directly
printing to a file from task context.
Otherwise it can unintentionally expose security sensitive,
raw pointer values.

Use regular pointer formatting instead.

Link: https://lore.kernel.org/lkml/20250113171731-dc10e3c1-da64-4af0-b767-7c7070468023@linutronix.de/
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Michael Mueller <mimu@linux.ibm.com>
Tested-by: Michael Mueller <mimu@linux.ibm.com>
Link: https://lore.kernel.org/r/20250217-restricted-pointers-s390-v1-2-0e4ace75d8aa@linutronix.de
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Message-ID: <20250217-restricted-pointers-s390-v1-2-0e4ace75d8aa@linutronix.de>
2025-03-17 08:55:46 +00:00
Claudio Imbrenda
d8dfda5af0 KVM: s390: pv: fix race when making a page secure
Holding the pte lock for the page that is being converted to secure is
needed to avoid races. A previous commit removed the locking, which
caused issues. Fix by locking the pte again.

Fixes: 5cbe24350b ("KVM: s390: move pv gmap functions into kvm")
Reported-by: David Hildenbrand <david@redhat.com>
Tested-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[david@redhat.com: replace use of get_locked_pte() with folio_walk_start()]
Link: https://lore.kernel.org/r/20250312184912.269414-2-imbrenda@linux.ibm.com
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20250312184912.269414-2-imbrenda@linux.ibm.com>
2025-03-14 15:24:19 +01:00
Heiko Carstens
aaab4a4ff3 s390/kvm: Convert MACHINE_HAS_ESOP to machine_has_esop()
Use static branch(es) to implement and use machine_has_esop() instead
of a runtime check via MACHINE_HAS_ESOP.

Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04 17:18:06 +01:00
Heiko Carstens
17d3804808 s390/tlb: Convert MACHINE_HAS_TLB_GUEST to machine_has_tlb_guest()
Use static branch(es) to implement and use machine_has_tlb_guest()
instead of a runtime check via MACHINE_HAS_TLB_GUEST.

Also add sclp_early_detect_machine_features() in order to allow for
feature detection from the decompressor.

Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04 17:18:06 +01:00
Heiko Carstens
42805261fc s390/cpufeature: Convert MACHINE_HAS_GS to cpu_has_gs()
Convert MACHINE_HAS_... to cpu_has_...() which uses test_facility() instead
of testing the machine_flags lowcore member if the feature is present.

test_facility() generates better code since it results in a static branch
without accessing memory. The branch is patched via alternatives by the
decompressor depending on the availability of the required facility.

Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04 17:18:04 +01:00
Nam Cao
7ff22753d8 KVM: s390: Switch to use hrtimer_setup()
hrtimer_setup() takes the callback function pointer as argument and
initializes the timer completely.

Replace hrtimer_init() and the open coded initialization of
hrtimer::function with the new setup mechanism.

Patch was created by using Coccinelle.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Link: https://lore.kernel.org/all/637865c62963fb8cddf6c4368ca12434988a8c27.1738746821.git.namcao@linutronix.de
2025-02-18 10:32:30 +01:00
Claudio Imbrenda
c9f721ed8e KVM: s390: move some gmap shadowing functions away from mm/gmap.c
Move some gmap shadowing functions from mm/gmap.c to kvm/kvm-s390.c and
the newly created kvm/gmap-vsie.c

This is a step toward removing gmap from mm.

Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com>
Link: https://lore.kernel.org/r/20250123144627.312456-10-imbrenda@linux.ibm.com
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20250123144627.312456-10-imbrenda@linux.ibm.com>
2025-01-31 12:03:52 +01:00
Claudio Imbrenda
3762e905ec KVM: s390: use __kvm_faultin_pfn()
Refactor the existing page fault handling code to use __kvm_faultin_pfn().

This possible now that memslots are always present.

Acked-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com>
Link: https://lore.kernel.org/r/20250123144627.312456-7-imbrenda@linux.ibm.com
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20250123144627.312456-7-imbrenda@linux.ibm.com>
2025-01-31 12:03:52 +01:00
Claudio Imbrenda
5cbe24350b KVM: s390: move pv gmap functions into kvm
Move gmap related functions from kernel/uv into kvm.

Create a new file to collect gmap-related functions.

Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com>
[fixed unpack_one(), thanks mhartmay@linux.ibm.com]
Link: https://lore.kernel.org/r/20250123144627.312456-6-imbrenda@linux.ibm.com
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20250123144627.312456-6-imbrenda@linux.ibm.com>
2025-01-31 12:03:52 +01:00
Claudio Imbrenda
413c98f24c KVM: s390: fake memslot for ucontrol VMs
Create a fake memslot for ucontrol VMs. The fake memslot identity-maps
userspace.

Now memslots will always be present, and ucontrol is not a special case
anymore.

Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20250123144627.312456-4-imbrenda@linux.ibm.com
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20250123144627.312456-4-imbrenda@linux.ibm.com>
2025-01-31 12:03:52 +01:00
Claudio Imbrenda
decff09adb KVM: s390: wrapper for KVM_BUG
Wrap the call to KVM_BUG; this reduces code duplication and improves
readability.

Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com>
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20250123144627.312456-3-imbrenda@linux.ibm.com
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20250123144627.312456-3-imbrenda@linux.ibm.com>
2025-01-31 12:03:52 +01:00
Linus Torvalds
509f806f7f more s390 updates for 6.13 merge window
- Add swap entry for hugetlbfs support
 
 - Add PTE_MARKER support for hugetlbs mappings; this fixes a regression
   (possible page fault loop) which was introduced when support for
   UFFDIO_POISON for hugetlbfs was added
 
 - Add ARCH_HAS_PREEMPT_LAZY and PREEMPT_DYNAMIC support
 
 - Mark IRQ entries in entry code, so that stack tracers can filter out the
   non-IRQ parts of stack traces. This fixes stack depot capacity limit
   warnings, since without filtering the number of unique stack traces is
   huge
 
 - In PCI code fix leak of struct zpci_dev object, and fix potential double
   remove of hotplug slot
 
 - Fix pagefault_disable() / pagefault_enable() unbalance in
   arch_stack_user_walk_common()
 
 - A couple of inline assembly optimizations, more cmpxchg() to
   try_cmpxchg() conversions, and removal of usages of xchg() and cmpxchg()
   on one and two byte memory areas
 
 - Various other small improvements and cleanups
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEECMNfWEw3SLnmiLkZIg7DeRspbsIFAmdJ3WoACgkQIg7DeRsp
 bsJt1RAAtlkbeN4+eVeYM4vBwHvgfAY/5Ii2wdHO2qwPHqBVkRtsqrmyewE/tVCF
 PZsYBXDDrzyAtLMqjlNGDQ1QexNLn4BELgSIysr45mxwMq1W33BiXvb8I5uK/V/7
 /TcW2s1daJKKrbk+HBA8ZTwna5SeUSoZuh9y/n9SKVC4rRkWdeL7G1RRNQtafDlg
 aELCo17iHDZNoHeoRStOimZqVBwko6IQqQH4DCx2S4+J6nKQBGRyzGWIkLRoUxr6
 MgNLrxekWjkoqAnXM0Ztb7LYg6AS/iOuGbqg/xLi1VJSWNCIf9zLpDs++SdFHoTU
 n4Cj07IHR4OLQ1YB+EX2uPY7rJw0tPt0g/dgmYYi3uP88hJ7VYFOtfJx/UGlid2q
 3l7wXNwtg+CJtw0Ey+21cMdmnOffxH9c3nBPahe7zK5k1GKjXDOfWEcmucG0zW5K
 qYI5m7vAZAX4ve1362DOgJei/1uxGuMQQZsobHpwfhcGXzLZ2AZY45Ls86nQzHua
 KpupybWQe70hQYk9hUw+M/ShChuH8dhnPjx51T0r/0E0BdU6Q20xLPLWx/2jRzUb
 FlFg7WtVw2y45eQCFPbtVsoVzDCpfpfgTw5rrDsjFf/twS0E3ubmTC1rLr4YB+5m
 5cjPys/SYpQWUi3wQFTQ6dL3w0+vWXlQmTi5ChcxTZF2ytwP+yg=
 =cfmM
 -----END PGP SIGNATURE-----

Merge tag 's390-6.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull more s390 updates from Heiko Carstens:

 - Add swap entry for hugetlbfs support

 - Add PTE_MARKER support for hugetlbs mappings; this fixes a regression
   (possible page fault loop) which was introduced when support for
   UFFDIO_POISON for hugetlbfs was added

 - Add ARCH_HAS_PREEMPT_LAZY and PREEMPT_DYNAMIC support

 - Mark IRQ entries in entry code, so that stack tracers can filter out
   the non-IRQ parts of stack traces. This fixes stack depot capacity
   limit warnings, since without filtering the number of unique stack
   traces is huge

 - In PCI code fix leak of struct zpci_dev object, and fix potential
   double remove of hotplug slot

 - Fix pagefault_disable() / pagefault_enable() unbalance in
   arch_stack_user_walk_common()

 - A couple of inline assembly optimizations, more cmpxchg() to
   try_cmpxchg() conversions, and removal of usages of xchg() and
   cmpxchg() on one and two byte memory areas

 - Various other small improvements and cleanups

* tag 's390-6.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (27 commits)
  Revert "s390/mm: Allow large pages for KASAN shadow mapping"
  s390/spinlock: Use flag output constraint for arch_cmpxchg_niai8()
  s390/spinlock: Use R constraint for arch_load_niai4()
  s390/spinlock: Generate shorter code for arch_spin_unlock()
  s390/spinlock: Remove condition code clobber from arch_spin_unlock()
  s390/spinlock: Use symbolic names in inline assemblies
  s390: Support PREEMPT_DYNAMIC
  s390/pci: Fix potential double remove of hotplug slot
  s390/pci: Fix leak of struct zpci_dev when zpci_add_device() fails
  s390/mm/hugetlbfs: Add missing includes
  s390/mm: Add PTE_MARKER support for hugetlbfs mappings
  s390/mm: Introduce region-third and segment table swap entries
  s390/mm: Introduce region-third and segment table entry present bits
  s390/mm: Rearrange region-third and segment table entry SW bits
  KVM: s390: Increase size of union sca_utility to four bytes
  KVM: s390: Remove one byte cmpxchg() usage
  KVM: s390: Use try_cmpxchg() instead of cmpxchg() loops
  s390/ap: Replace xchg() with WRITE_ONCE()
  s390/mm: Allow large pages for KASAN shadow mapping
  s390: Add ARCH_HAS_PREEMPT_LAZY support
  ...
2024-11-29 10:40:52 -08:00
Heiko Carstens
5618c53d96 KVM: s390: Use try_cmpxchg() instead of cmpxchg() loops
Convert all cmpxchg() loops to try_cmpxchg() loops. With gcc 14 and the
usage of flag output operands in try_cmpxchg() this allows the compiler to
generate slightly better code.

Acked-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20241126102515.3178914-2-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-11-27 12:55:15 +01:00
Linus Torvalds
9f16d5e6f2 The biggest change here is eliminating the awful idea that KVM had, of
essentially guessing which pfns are refcounted pages.  The reason to
 do so was that KVM needs to map both non-refcounted pages (for example
 BARs of VFIO devices) and VM_PFNMAP/VM_MIXMEDMAP VMAs that contain
 refcounted pages.  However, the result was security issues in the past,
 and more recently the inability to map VM_IO and VM_PFNMAP memory
 that _is_ backed by struct page but is not refcounted.  In particular
 this broke virtio-gpu blob resources (which directly map host graphics
 buffers into the guest as "vram" for the virtio-gpu device) with the
 amdgpu driver, because amdgpu allocates non-compound higher order pages
 and the tail pages could not be mapped into KVM.
 
 This requires adjusting all uses of struct page in the per-architecture
 code, to always work on the pfn whenever possible.  The large series that
 did this, from David Stevens and Sean Christopherson, also cleaned up
 substantially the set of functions that provided arch code with the
 pfn for a host virtual addresses.  The previous maze of twisty little
 passages, all different, is replaced by five functions (__gfn_to_page,
 __kvm_faultin_pfn, the non-__ versions of these two, and kvm_prefetch_pages)
 saving almost 200 lines of code.
 
 ARM:
 
 * Support for stage-1 permission indirection (FEAT_S1PIE) and
   permission overlays (FEAT_S1POE), including nested virt + the
   emulated page table walker
 
 * Introduce PSCI SYSTEM_OFF2 support to KVM + client driver. This call
   was introduced in PSCIv1.3 as a mechanism to request hibernation,
   similar to the S4 state in ACPI
 
 * Explicitly trap + hide FEAT_MPAM (QoS controls) from KVM guests. As
   part of it, introduce trivial initialization of the host's MPAM
   context so KVM can use the corresponding traps
 
 * PMU support under nested virtualization, honoring the guest
   hypervisor's trap configuration and event filtering when running a
   nested guest
 
 * Fixes to vgic ITS serialization where stale device/interrupt table
   entries are not zeroed when the mapping is invalidated by the VM
 
 * Avoid emulated MMIO completion if userspace has requested synchronous
   external abort injection
 
 * Various fixes and cleanups affecting pKVM, vCPU initialization, and
   selftests
 
 LoongArch:
 
 * Add iocsr and mmio bus simulation in kernel.
 
 * Add in-kernel interrupt controller emulation.
 
 * Add support for virtualization extensions to the eiointc irqchip.
 
 PPC:
 
 * Drop lingering and utterly obsolete references to PPC970 KVM, which was
   removed 10 years ago.
 
 * Fix incorrect documentation references to non-existing ioctls
 
 RISC-V:
 
 * Accelerate KVM RISC-V when running as a guest
 
 * Perf support to collect KVM guest statistics from host side
 
 s390:
 
 * New selftests: more ucontrol selftests and CPU model sanity checks
 
 * Support for the gen17 CPU model
 
 * List registers supported by KVM_GET/SET_ONE_REG in the documentation
 
 x86:
 
 * Cleanup KVM's handling of Accessed and Dirty bits to dedup code, improve
   documentation, harden against unexpected changes.  Even if the hardware
   A/D tracking is disabled, it is possible to use the hardware-defined A/D
   bits to track if a PFN is Accessed and/or Dirty, and that removes a lot
   of special cases.
 
 * Elide TLB flushes when aging secondary PTEs, as has been done in x86's
   primary MMU for over 10 years.
 
 * Recover huge pages in-place in the TDP MMU when dirty page logging is
   toggled off, instead of zapping them and waiting until the page is
   re-accessed to create a huge mapping.  This reduces vCPU jitter.
 
 * Batch TLB flushes when dirty page logging is toggled off.  This reduces
   the time it takes to disable dirty logging by ~3x.
 
 * Remove the shrinker that was (poorly) attempting to reclaim shadow page
   tables in low-memory situations.
 
 * Clean up and optimize KVM's handling of writes to MSR_IA32_APICBASE.
 
 * Advertise CPUIDs for new instructions in Clearwater Forest
 
 * Quirk KVM's misguided behavior of initialized certain feature MSRs to
   their maximum supported feature set, which can result in KVM creating
   invalid vCPU state.  E.g. initializing PERF_CAPABILITIES to a non-zero
   value results in the vCPU having invalid state if userspace hides PDCM
   from the guest, which in turn can lead to save/restore failures.
 
 * Fix KVM's handling of non-canonical checks for vCPUs that support LA57
   to better follow the "architecture", in quotes because the actual
   behavior is poorly documented.  E.g. most MSR writes and descriptor
   table loads ignore CR4.LA57 and operate purely on whether the CPU
   supports LA57.
 
 * Bypass the register cache when querying CPL from kvm_sched_out(), as
   filling the cache from IRQ context is generally unsafe; harden the
   cache accessors to try to prevent similar issues from occuring in the
   future.  The issue that triggered this change was already fixed in 6.12,
   but was still kinda latent.
 
 * Advertise AMD_IBPB_RET to userspace, and fix a related bug where KVM
   over-advertises SPEC_CTRL when trying to support cross-vendor VMs.
 
 * Minor cleanups
 
 * Switch hugepage recovery thread to use vhost_task.  These kthreads can
   consume significant amounts of CPU time on behalf of a VM or in response
   to how the VM behaves (for example how it accesses its memory); therefore
   KVM tried to place the thread in the VM's cgroups and charge the CPU
   time consumed by that work to the VM's container.  However the kthreads
   did not process SIGSTOP/SIGCONT, and therefore cgroups which had KVM
   instances inside could not complete freezing.  Fix this by replacing the
   kthread with a PF_USER_WORKER thread, via the vhost_task abstraction.
   Another 100+ lines removed, with generally better behavior too like
   having these threads properly parented in the process tree.
 
 * Revert a workaround for an old CPU erratum (Nehalem/Westmere) that didn't
   really work; there was really nothing to work around anyway: the broken
   patch was meant to fix nested virtualization, but the PERF_GLOBAL_CTRL
   MSR is virtualized and therefore unaffected by the erratum.
 
 * Fix 6.12 regression where CONFIG_KVM will be built as a module even
   if asked to be builtin, as long as neither KVM_INTEL nor KVM_AMD is 'y'.
 
 x86 selftests:
 
 * x86 selftests can now use AVX.
 
 Documentation:
 
 * Use rST internal links
 
 * Reorganize the introduction to the API document
 
 Generic:
 
 * Protect vcpu->pid accesses outside of vcpu->mutex with a rwlock instead
   of RCU, so that running a vCPU on a different task doesn't encounter long
   due to having to wait for all CPUs become quiescent.  In general both reads
   and writes are rare, but userspace that supports confidential computing is
   introducing the use of "helper" vCPUs that may jump from one host processor
   to another.  Those will be very happy to trigger a synchronize_rcu(), and
   the effect on performance is quite the disaster.
 -----BEGIN PGP SIGNATURE-----
 
 iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmc9MRYUHHBib256aW5p
 QHJlZGhhdC5jb20ACgkQv/vSX3jHroP00QgArxqxBIGLCW5t7bw7vtNq63QYRyh4
 dTiDguLiYQJ+AXmnRu11R6aPC7HgMAvlFCCmH+GEce4WEgt26hxCmncJr/aJOSwS
 letCS7TrME16PeZvh25A1nhPBUw6mTF1qqzgcdHMrqXG8LuHoGcKYGSRVbkf3kfI
 1ZoMq1r8ChXbVVmCx9DQ3gw1TVr5Dpjs2voLh8rDSE9Xpw0tVVabHu3/NhQEz/F+
 t8/nRaqH777icCHIf9PCk5HnarHxLAOvhM2M0Yj09PuBcE5fFQxpxltw/qiKQqqW
 ep4oquojGl87kZnhlDaac2UNtK90Ws+WxxvCwUmbvGN0ZJVaQwf4FvTwig==
 =lWpE
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "The biggest change here is eliminating the awful idea that KVM had of
  essentially guessing which pfns are refcounted pages.

  The reason to do so was that KVM needs to map both non-refcounted
  pages (for example BARs of VFIO devices) and VM_PFNMAP/VM_MIXMEDMAP
  VMAs that contain refcounted pages.

  However, the result was security issues in the past, and more recently
  the inability to map VM_IO and VM_PFNMAP memory that _is_ backed by
  struct page but is not refcounted. In particular this broke virtio-gpu
  blob resources (which directly map host graphics buffers into the
  guest as "vram" for the virtio-gpu device) with the amdgpu driver,
  because amdgpu allocates non-compound higher order pages and the tail
  pages could not be mapped into KVM.

  This requires adjusting all uses of struct page in the
  per-architecture code, to always work on the pfn whenever possible.
  The large series that did this, from David Stevens and Sean
  Christopherson, also cleaned up substantially the set of functions
  that provided arch code with the pfn for a host virtual addresses.

  The previous maze of twisty little passages, all different, is
  replaced by five functions (__gfn_to_page, __kvm_faultin_pfn, the
  non-__ versions of these two, and kvm_prefetch_pages) saving almost
  200 lines of code.

  ARM:

   - Support for stage-1 permission indirection (FEAT_S1PIE) and
     permission overlays (FEAT_S1POE), including nested virt + the
     emulated page table walker

   - Introduce PSCI SYSTEM_OFF2 support to KVM + client driver. This
     call was introduced in PSCIv1.3 as a mechanism to request
     hibernation, similar to the S4 state in ACPI

   - Explicitly trap + hide FEAT_MPAM (QoS controls) from KVM guests. As
     part of it, introduce trivial initialization of the host's MPAM
     context so KVM can use the corresponding traps

   - PMU support under nested virtualization, honoring the guest
     hypervisor's trap configuration and event filtering when running a
     nested guest

   - Fixes to vgic ITS serialization where stale device/interrupt table
     entries are not zeroed when the mapping is invalidated by the VM

   - Avoid emulated MMIO completion if userspace has requested
     synchronous external abort injection

   - Various fixes and cleanups affecting pKVM, vCPU initialization, and
     selftests

  LoongArch:

   - Add iocsr and mmio bus simulation in kernel.

   - Add in-kernel interrupt controller emulation.

   - Add support for virtualization extensions to the eiointc irqchip.

  PPC:

   - Drop lingering and utterly obsolete references to PPC970 KVM, which
     was removed 10 years ago.

   - Fix incorrect documentation references to non-existing ioctls

  RISC-V:

   - Accelerate KVM RISC-V when running as a guest

   - Perf support to collect KVM guest statistics from host side

  s390:

   - New selftests: more ucontrol selftests and CPU model sanity checks

   - Support for the gen17 CPU model

   - List registers supported by KVM_GET/SET_ONE_REG in the
     documentation

  x86:

   - Cleanup KVM's handling of Accessed and Dirty bits to dedup code,
     improve documentation, harden against unexpected changes.

     Even if the hardware A/D tracking is disabled, it is possible to
     use the hardware-defined A/D bits to track if a PFN is Accessed
     and/or Dirty, and that removes a lot of special cases.

   - Elide TLB flushes when aging secondary PTEs, as has been done in
     x86's primary MMU for over 10 years.

   - Recover huge pages in-place in the TDP MMU when dirty page logging
     is toggled off, instead of zapping them and waiting until the page
     is re-accessed to create a huge mapping. This reduces vCPU jitter.

   - Batch TLB flushes when dirty page logging is toggled off. This
     reduces the time it takes to disable dirty logging by ~3x.

   - Remove the shrinker that was (poorly) attempting to reclaim shadow
     page tables in low-memory situations.

   - Clean up and optimize KVM's handling of writes to
     MSR_IA32_APICBASE.

   - Advertise CPUIDs for new instructions in Clearwater Forest

   - Quirk KVM's misguided behavior of initialized certain feature MSRs
     to their maximum supported feature set, which can result in KVM
     creating invalid vCPU state. E.g. initializing PERF_CAPABILITIES to
     a non-zero value results in the vCPU having invalid state if
     userspace hides PDCM from the guest, which in turn can lead to
     save/restore failures.

   - Fix KVM's handling of non-canonical checks for vCPUs that support
     LA57 to better follow the "architecture", in quotes because the
     actual behavior is poorly documented. E.g. most MSR writes and
     descriptor table loads ignore CR4.LA57 and operate purely on
     whether the CPU supports LA57.

   - Bypass the register cache when querying CPL from kvm_sched_out(),
     as filling the cache from IRQ context is generally unsafe; harden
     the cache accessors to try to prevent similar issues from occuring
     in the future. The issue that triggered this change was already
     fixed in 6.12, but was still kinda latent.

   - Advertise AMD_IBPB_RET to userspace, and fix a related bug where
     KVM over-advertises SPEC_CTRL when trying to support cross-vendor
     VMs.

   - Minor cleanups

   - Switch hugepage recovery thread to use vhost_task.

     These kthreads can consume significant amounts of CPU time on
     behalf of a VM or in response to how the VM behaves (for example
     how it accesses its memory); therefore KVM tried to place the
     thread in the VM's cgroups and charge the CPU time consumed by that
     work to the VM's container.

     However the kthreads did not process SIGSTOP/SIGCONT, and therefore
     cgroups which had KVM instances inside could not complete freezing.

     Fix this by replacing the kthread with a PF_USER_WORKER thread, via
     the vhost_task abstraction. Another 100+ lines removed, with
     generally better behavior too like having these threads properly
     parented in the process tree.

   - Revert a workaround for an old CPU erratum (Nehalem/Westmere) that
     didn't really work; there was really nothing to work around anyway:
     the broken patch was meant to fix nested virtualization, but the
     PERF_GLOBAL_CTRL MSR is virtualized and therefore unaffected by the
     erratum.

   - Fix 6.12 regression where CONFIG_KVM will be built as a module even
     if asked to be builtin, as long as neither KVM_INTEL nor KVM_AMD is
     'y'.

  x86 selftests:

   - x86 selftests can now use AVX.

  Documentation:

   - Use rST internal links

   - Reorganize the introduction to the API document

  Generic:

   - Protect vcpu->pid accesses outside of vcpu->mutex with a rwlock
     instead of RCU, so that running a vCPU on a different task doesn't
     encounter long due to having to wait for all CPUs become quiescent.

     In general both reads and writes are rare, but userspace that
     supports confidential computing is introducing the use of "helper"
     vCPUs that may jump from one host processor to another. Those will
     be very happy to trigger a synchronize_rcu(), and the effect on
     performance is quite the disaster"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (298 commits)
  KVM: x86: Break CONFIG_KVM_X86's direct dependency on KVM_INTEL || KVM_AMD
  KVM: x86: add back X86_LOCAL_APIC dependency
  Revert "KVM: VMX: Move LOAD_IA32_PERF_GLOBAL_CTRL errata handling out of setup_vmcs_config()"
  KVM: x86: switch hugepage recovery thread to vhost_task
  KVM: x86: expose MSR_PLATFORM_INFO as a feature MSR
  x86: KVM: Advertise CPUIDs for new instructions in Clearwater Forest
  Documentation: KVM: fix malformed table
  irqchip/loongson-eiointc: Add virt extension support
  LoongArch: KVM: Add irqfd support
  LoongArch: KVM: Add PCHPIC user mode read and write functions
  LoongArch: KVM: Add PCHPIC read and write functions
  LoongArch: KVM: Add PCHPIC device support
  LoongArch: KVM: Add EIOINTC user mode read and write functions
  LoongArch: KVM: Add EIOINTC read and write functions
  LoongArch: KVM: Add EIOINTC device support
  LoongArch: KVM: Add IPI user mode read and write function
  LoongArch: KVM: Add IPI read and write function
  LoongArch: KVM: Add IPI device support
  LoongArch: KVM: Add iocsr and mmio bus simulation in kernel
  KVM: arm64: Pass on SVE mapping failures
  ...
2024-11-23 16:00:50 -08:00
Heiko Carstens
4e20996f0d s390/kvm: Convert to use flag output macros
Use flag output macros in inline asm to allow for better code generation if
the compiler has support for the flag output constraint.

Reviewed-by: Juergen Christ <jchrist@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-11-13 14:31:33 +01:00
Hendrik Brueckner
85a9e680d4 KVM: s390: add gen17 facilities to CPU model
Add gen17 facilities and let KVM_CAP_S390_VECTOR_REGISTERS handle
the enablement of the vector extension facilities.

Signed-off-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Link: https://lore.kernel.org/r/20241107152319.77816-4-brueckner@linux.ibm.com
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Message-ID: <20241107152319.77816-4-brueckner@linux.ibm.com>
2024-11-11 12:07:51 +00:00
Hendrik Brueckner
2c2cc82738 KVM: s390: add msa11 to cpu model
Message-security-assist 11 introduces pckmo subfunctions to encrypt
hmac keys.

Signed-off-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Link: https://lore.kernel.org/r/20241107152319.77816-3-brueckner@linux.ibm.com
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Message-ID: <20241107152319.77816-3-brueckner@linux.ibm.com>
2024-11-11 12:07:51 +00:00
Hendrik Brueckner
66ff6bf59b KVM: s390: add concurrent-function facility to cpu model
Adding support for concurrent-functions facility which provides
additional subfunctions.

Signed-off-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Link: https://lore.kernel.org/r/20241107152319.77816-2-brueckner@linux.ibm.com
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Message-ID: <20241107152319.77816-2-brueckner@linux.ibm.com>
2024-11-11 12:07:51 +00:00
Claudio Imbrenda
34fb045edd s390/kvm: Mask extra bits from program interrupt code
The program interrupt code has some extra bits that are sometimes set
by hardware for various reasons; those bits should be ignored when the
program interrupt number is needed for interrupt handling.

Fixes: 05066cafa9 ("s390/mm/fault: Handle guest-related program interrupts in KVM")
Reported-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Tested-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Link: https://lore.kernel.org/r/20241031120316.25462-1-imbrenda@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-11-07 10:23:43 +01:00
Claudio Imbrenda
64844729a6 s390/kvm: Initialize uninitialized flags variable
The flags variable was being used uninitialized.
Initialize it to 0 as expected.

For some reason neither gcc nor clang reported a warning.

Fixes: 05066cafa9 ("s390/mm/fault: Handle guest-related program interrupts in KVM")
Reported-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20241030161906.85476-1-imbrenda@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-10-31 10:50:07 +01:00
Claudio Imbrenda
8cdebf47ed s390/kvm: Stop using gmap_{en,dis}able()
Stop using gmap_enable(), gmap_disable(), gmap_get_enabled().

The correct guest ASCE is passed as a parameter of sie64a(), there is
no need to save the current gmap in lowcore.

Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Link: https://lore.kernel.org/r/20241022120601.167009-7-imbrenda@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-10-29 11:49:19 +01:00
Claudio Imbrenda
05066cafa9 s390/mm/fault: Handle guest-related program interrupts in KVM
Any program interrupt that happens in the host during the execution of
a KVM guest will now short circuit the fault handler and return to KVM
immediately. Guest fault handling (including pfault) will happen
entirely inside KVM.

When sie64a() returns zero, current->thread.gmap_int_code will contain
the program interrupt number that caused the exit, or zero if the exit
was not caused by a host program interrupt.

KVM will now take care of handling all guest faults in vcpu_post_run().

Since gmap faults will not be visible by the rest of the kernel, remove
GMAP_FAULT, the linux fault handlers for secure execution faults, the
exception table entries for the sie instruction, the nop padding after
the sie instruction, and all other references to guest faults from the
s390 code.

Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Co-developed-by: Heiko Carstens <hca@linux.ibm.com>
Link: https://lore.kernel.org/r/20241022120601.167009-6-imbrenda@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-10-29 11:49:18 +01:00
Claudio Imbrenda
ca3c6dc3a9 s390/kvm: Remove kvm_arch_fault_in_page()
kvm_arch_fault_in_page() is a useless wrapper around gmap_fault(); just
use gmap_fault() directly instead.

Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20241022120601.167009-3-imbrenda@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-10-29 11:49:18 +01:00
Hariharan Mari
09c38ad044 KVM: s390: Fix SORTL and DFLTCC instruction format error in __insn32_query
The __insn32_query() function incorrectly uses the RRF instruction format
for both the SORTL (RRE format) and DFLTCC (RRF format) instructions.
To fix this issue, add separate query functions for SORTL and DFLTCC that
use the appropriate instruction formats.

Additionally pass the query operand as a pointer to the entire array
of 32 elements to slightly optimize performance and readability.

Fixes: d668139718 ("KVM: s390: provide query function for instructions returning 32 byte")
Suggested-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Juergen Christ <jchrist@linux.ibm.com>
Signed-off-by: Hariharan Mari <hari55@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2024-08-19 07:51:14 +00:00
Linus Torvalds
2c9b351240 ARM:
* Initial infrastructure for shadow stage-2 MMUs, as part of nested
   virtualization enablement
 
 * Support for userspace changes to the guest CTR_EL0 value, enabling
   (in part) migration of VMs between heterogenous hardware
 
 * Fixes + improvements to pKVM's FF-A proxy, adding support for v1.1 of
   the protocol
 
 * FPSIMD/SVE support for nested, including merged trap configuration
   and exception routing
 
 * New command-line parameter to control the WFx trap behavior under KVM
 
 * Introduce kCFI hardening in the EL2 hypervisor
 
 * Fixes + cleanups for handling presence/absence of FEAT_TCRX
 
 * Miscellaneous fixes + documentation updates
 
 LoongArch:
 
 * Add paravirt steal time support.
 
 * Add support for KVM_DIRTY_LOG_INITIALLY_SET.
 
 * Add perf kvm-stat support for loongarch.
 
 RISC-V:
 
 * Redirect AMO load/store access fault traps to guest
 
 * perf kvm stat support
 
 * Use guest files for IMSIC virtualization, when available
 
 ONE_REG support for the Zimop, Zcmop, Zca, Zcf, Zcd, Zcb and Zawrs ISA
 extensions is coming through the RISC-V tree.
 
 s390:
 
 * Assortment of tiny fixes which are not time critical
 
 x86:
 
 * Fixes for Xen emulation.
 
 * Add a global struct to consolidate tracking of host values, e.g. EFER
 
 * Add KVM_CAP_X86_APIC_BUS_CYCLES_NS to allow configuring the effective APIC
   bus frequency, because TDX.
 
 * Print the name of the APICv/AVIC inhibits in the relevant tracepoint.
 
 * Clean up KVM's handling of vendor specific emulation to consistently act on
   "compatible with Intel/AMD", versus checking for a specific vendor.
 
 * Drop MTRR virtualization, and instead always honor guest PAT on CPUs
   that support self-snoop.
 
 * Update to the newfangled Intel CPU FMS infrastructure.
 
 * Don't advertise IA32_PERF_GLOBAL_OVF_CTRL as an MSR-to-be-saved, as it reads
   '0' and writes from userspace are ignored.
 
 * Misc cleanups
 
 x86 - MMU:
 
 * Small cleanups, renames and refactoring extracted from the upcoming
   Intel TDX support.
 
 * Don't allocate kvm_mmu_page.shadowed_translation for shadow pages that can't
   hold leafs SPTEs.
 
 * Unconditionally drop mmu_lock when allocating TDP MMU page tables for eager
   page splitting, to avoid stalling vCPUs when splitting huge pages.
 
 * Bug the VM instead of simply warning if KVM tries to split a SPTE that is
   non-present or not-huge.  KVM is guaranteed to end up in a broken state
   because the callers fully expect a valid SPTE, it's all but dangerous
   to let more MMU changes happen afterwards.
 
 x86 - AMD:
 
 * Make per-CPU save_area allocations NUMA-aware.
 
 * Force sev_es_host_save_area() to be inlined to avoid calling into an
   instrumentable function from noinstr code.
 
 * Base support for running SEV-SNP guests.  API-wise, this includes
   a new KVM_X86_SNP_VM type, encrypting/measure the initial image into
   guest memory, and finalizing it before launching it.  Internally,
   there are some gmem/mmu hooks needed to prepare gmem-allocated pages
   before mapping them into guest private memory ranges.
 
   This includes basic support for attestation guest requests, enough to
   say that KVM supports the GHCB 2.0 specification.
 
   There is no support yet for loading into the firmware those signing
   keys to be used for attestation requests, and therefore no need yet
   for the host to provide certificate data for those keys.  To support
   fetching certificate data from userspace, a new KVM exit type will be
   needed to handle fetching the certificate from userspace. An attempt to
   define a new KVM_EXIT_COCO/KVM_EXIT_COCO_REQ_CERTS exit type to handle
   this was introduced in v1 of this patchset, but is still being discussed
   by community, so for now this patchset only implements a stub version
   of SNP Extended Guest Requests that does not provide certificate data.
 
 x86 - Intel:
 
 * Remove an unnecessary EPT TLB flush when enabling hardware.
 
 * Fix a series of bugs that cause KVM to fail to detect nested pending posted
   interrupts as valid wake eents for a vCPU executing HLT in L2 (with
   HLT-exiting disable by L1).
 
 * KVM: x86: Suppress MMIO that is triggered during task switch emulation
 
   Explicitly suppress userspace emulated MMIO exits that are triggered when
   emulating a task switch as KVM doesn't support userspace MMIO during
   complex (multi-step) emulation.  Silently ignoring the exit request can
   result in the WARN_ON_ONCE(vcpu->mmio_needed) firing if KVM exits to
   userspace for some other reason prior to purging mmio_needed.
 
   See commit 0dc902267c ("KVM: x86: Suppress pending MMIO write exits if
   emulator detects exception") for more details on KVM's limitations with
   respect to emulated MMIO during complex emulator flows.
 
 Generic:
 
 * Rename the AS_UNMOVABLE flag that was introduced for KVM to AS_INACCESSIBLE,
   because the special casing needed by these pages is not due to just
   unmovability (and in fact they are only unmovable because the CPU cannot
   access them).
 
 * New ioctl to populate the KVM page tables in advance, which is useful to
   mitigate KVM page faults during guest boot or after live migration.
   The code will also be used by TDX, but (probably) not through the ioctl.
 
 * Enable halt poll shrinking by default, as Intel found it to be a clear win.
 
 * Setup empty IRQ routing when creating a VM to avoid having to synchronize
   SRCU when creating a split IRQCHIP on x86.
 
 * Rework the sched_in/out() paths to replace kvm_arch_sched_in() with a flag
   that arch code can use for hooking both sched_in() and sched_out().
 
 * Take the vCPU @id as an "unsigned long" instead of "u32" to avoid
   truncating a bogus value from userspace, e.g. to help userspace detect bugs.
 
 * Mark a vCPU as preempted if and only if it's scheduled out while in the
   KVM_RUN loop, e.g. to avoid marking it preempted and thus writing guest
   memory when retrieving guest state during live migration blackout.
 
 Selftests:
 
 * Remove dead code in the memslot modification stress test.
 
 * Treat "branch instructions retired" as supported on all AMD Family 17h+ CPUs.
 
 * Print the guest pseudo-RNG seed only when it changes, to avoid spamming the
   log for tests that create lots of VMs.
 
 * Make the PMU counters test less flaky when counting LLC cache misses by
   doing CLFLUSH{OPT} in every loop iteration.
 -----BEGIN PGP SIGNATURE-----
 
 iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmaZQB0UHHBib256aW5p
 QHJlZGhhdC5jb20ACgkQv/vSX3jHroNkZwf/bv2jiENaLFNGPe/VqTKMQ6PHQLMG
 +sNHx6fJPP35gTM8Jqf0/7/ummZXcSuC1mWrzYbecZm7Oeg3vwNXHZ4LquwwX6Dv
 8dKcUzLbWDAC4WA3SKhi8C8RV2v6E7ohy69NtAJmFWTc7H95dtIQm6cduV2osTC3
 OEuHe1i8d9umk6couL9Qhm8hk3i9v2KgCsrfyNrQgLtS3hu7q6yOTR8nT0iH6sJR
 KE5A8prBQgLmF34CuvYDw4Hu6E4j+0QmIqodovg2884W1gZQ9LmcVqYPaRZGsG8S
 iDdbkualLKwiR1TpRr3HJGKWSFdc7RblbsnHRvHIZgFsMQiimh4HrBSCyQ==
 =zepX
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "ARM:

   - Initial infrastructure for shadow stage-2 MMUs, as part of nested
     virtualization enablement

   - Support for userspace changes to the guest CTR_EL0 value, enabling
     (in part) migration of VMs between heterogenous hardware

   - Fixes + improvements to pKVM's FF-A proxy, adding support for v1.1
     of the protocol

   - FPSIMD/SVE support for nested, including merged trap configuration
     and exception routing

   - New command-line parameter to control the WFx trap behavior under
     KVM

   - Introduce kCFI hardening in the EL2 hypervisor

   - Fixes + cleanups for handling presence/absence of FEAT_TCRX

   - Miscellaneous fixes + documentation updates

  LoongArch:

   - Add paravirt steal time support

   - Add support for KVM_DIRTY_LOG_INITIALLY_SET

   - Add perf kvm-stat support for loongarch

  RISC-V:

   - Redirect AMO load/store access fault traps to guest

   - perf kvm stat support

   - Use guest files for IMSIC virtualization, when available

  s390:

   - Assortment of tiny fixes which are not time critical

  x86:

   - Fixes for Xen emulation

   - Add a global struct to consolidate tracking of host values, e.g.
     EFER

   - Add KVM_CAP_X86_APIC_BUS_CYCLES_NS to allow configuring the
     effective APIC bus frequency, because TDX

   - Print the name of the APICv/AVIC inhibits in the relevant
     tracepoint

   - Clean up KVM's handling of vendor specific emulation to
     consistently act on "compatible with Intel/AMD", versus checking
     for a specific vendor

   - Drop MTRR virtualization, and instead always honor guest PAT on
     CPUs that support self-snoop

   - Update to the newfangled Intel CPU FMS infrastructure

   - Don't advertise IA32_PERF_GLOBAL_OVF_CTRL as an MSR-to-be-saved, as
     it reads '0' and writes from userspace are ignored

   - Misc cleanups

  x86 - MMU:

   - Small cleanups, renames and refactoring extracted from the upcoming
     Intel TDX support

   - Don't allocate kvm_mmu_page.shadowed_translation for shadow pages
     that can't hold leafs SPTEs

   - Unconditionally drop mmu_lock when allocating TDP MMU page tables
     for eager page splitting, to avoid stalling vCPUs when splitting
     huge pages

   - Bug the VM instead of simply warning if KVM tries to split a SPTE
     that is non-present or not-huge. KVM is guaranteed to end up in a
     broken state because the callers fully expect a valid SPTE, it's
     all but dangerous to let more MMU changes happen afterwards

  x86 - AMD:

   - Make per-CPU save_area allocations NUMA-aware

   - Force sev_es_host_save_area() to be inlined to avoid calling into
     an instrumentable function from noinstr code

   - Base support for running SEV-SNP guests. API-wise, this includes a
     new KVM_X86_SNP_VM type, encrypting/measure the initial image into
     guest memory, and finalizing it before launching it. Internally,
     there are some gmem/mmu hooks needed to prepare gmem-allocated
     pages before mapping them into guest private memory ranges

     This includes basic support for attestation guest requests, enough
     to say that KVM supports the GHCB 2.0 specification

     There is no support yet for loading into the firmware those signing
     keys to be used for attestation requests, and therefore no need yet
     for the host to provide certificate data for those keys.

     To support fetching certificate data from userspace, a new KVM exit
     type will be needed to handle fetching the certificate from
     userspace.

     An attempt to define a new KVM_EXIT_COCO / KVM_EXIT_COCO_REQ_CERTS
     exit type to handle this was introduced in v1 of this patchset, but
     is still being discussed by community, so for now this patchset
     only implements a stub version of SNP Extended Guest Requests that
     does not provide certificate data

  x86 - Intel:

   - Remove an unnecessary EPT TLB flush when enabling hardware

   - Fix a series of bugs that cause KVM to fail to detect nested
     pending posted interrupts as valid wake eents for a vCPU executing
     HLT in L2 (with HLT-exiting disable by L1)

   - KVM: x86: Suppress MMIO that is triggered during task switch
     emulation

     Explicitly suppress userspace emulated MMIO exits that are
     triggered when emulating a task switch as KVM doesn't support
     userspace MMIO during complex (multi-step) emulation

     Silently ignoring the exit request can result in the
     WARN_ON_ONCE(vcpu->mmio_needed) firing if KVM exits to userspace
     for some other reason prior to purging mmio_needed

     See commit 0dc902267c ("KVM: x86: Suppress pending MMIO write
     exits if emulator detects exception") for more details on KVM's
     limitations with respect to emulated MMIO during complex emulator
     flows

  Generic:

   - Rename the AS_UNMOVABLE flag that was introduced for KVM to
     AS_INACCESSIBLE, because the special casing needed by these pages
     is not due to just unmovability (and in fact they are only
     unmovable because the CPU cannot access them)

   - New ioctl to populate the KVM page tables in advance, which is
     useful to mitigate KVM page faults during guest boot or after live
     migration. The code will also be used by TDX, but (probably) not
     through the ioctl

   - Enable halt poll shrinking by default, as Intel found it to be a
     clear win

   - Setup empty IRQ routing when creating a VM to avoid having to
     synchronize SRCU when creating a split IRQCHIP on x86

   - Rework the sched_in/out() paths to replace kvm_arch_sched_in() with
     a flag that arch code can use for hooking both sched_in() and
     sched_out()

   - Take the vCPU @id as an "unsigned long" instead of "u32" to avoid
     truncating a bogus value from userspace, e.g. to help userspace
     detect bugs

   - Mark a vCPU as preempted if and only if it's scheduled out while in
     the KVM_RUN loop, e.g. to avoid marking it preempted and thus
     writing guest memory when retrieving guest state during live
     migration blackout

  Selftests:

   - Remove dead code in the memslot modification stress test

   - Treat "branch instructions retired" as supported on all AMD Family
     17h+ CPUs

   - Print the guest pseudo-RNG seed only when it changes, to avoid
     spamming the log for tests that create lots of VMs

   - Make the PMU counters test less flaky when counting LLC cache
     misses by doing CLFLUSH{OPT} in every loop iteration"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (227 commits)
  crypto: ccp: Add the SNP_VLEK_LOAD command
  KVM: x86/pmu: Add kvm_pmu_call() to simplify static calls of kvm_pmu_ops
  KVM: x86: Introduce kvm_x86_call() to simplify static calls of kvm_x86_ops
  KVM: x86: Replace static_call_cond() with static_call()
  KVM: SEV: Provide support for SNP_EXTENDED_GUEST_REQUEST NAE event
  x86/sev: Move sev_guest.h into common SEV header
  KVM: SEV: Provide support for SNP_GUEST_REQUEST NAE event
  KVM: x86: Suppress MMIO that is triggered during task switch emulation
  KVM: x86/mmu: Clean up make_huge_page_split_spte() definition and intro
  KVM: x86/mmu: Bug the VM if KVM tries to split a !hugepage SPTE
  KVM: selftests: x86: Add test for KVM_PRE_FAULT_MEMORY
  KVM: x86: Implement kvm_arch_vcpu_pre_fault_memory()
  KVM: x86/mmu: Make kvm_mmu_do_page_fault() return mapped level
  KVM: x86/mmu: Account pf_{fixed,emulate,spurious} in callers of "do page fault"
  KVM: x86/mmu: Bump pf_taken stat only in the "real" page fault handler
  KVM: Add KVM_PRE_FAULT_MEMORY vcpu ioctl to pre-populate guest memory
  KVM: Document KVM_PRE_FAULT_MEMORY ioctl
  mm, virt: merge AS_UNMOVABLE and AS_INACCESSIBLE
  perf kvm: Add kvm-stat for loongarch64
  LoongArch: KVM: Add PV steal time support in guest side
  ...
2024-07-20 12:41:03 -07:00
Linus Torvalds
1c7d0c3af5 s390 updates for 6.11 merge window
- Remove restrictions on PAI NNPA and crypto counters, enabling
   concurrent per-task and system-wide sampling and counting events
 
 - Switch to GENERIC_CPU_DEVICES by setting up the CPU present mask in
   the architecture code and letting the generic code handle CPU bring-up
 
 - Add support for the diag204 busy indication facility to prevent
   undesirable blocking during hypervisor logical CPU utilization
   queries. Implement results caching
 
 - Improve the handling of Store Data SCLP events by suppressing
   unnecessary warning, preventing buffer release in I/O during failures,
   and adding timeout handling for Store Data requests to address potential
   firmware issues
 
 - Provide optimized __arch_hweight*() implementations
 
 - Remove the unnecessary CPU KOBJ_CHANGE uevents generated during topology
   updates, as they are unused and also not present on other architectures
 
 - Cleanup atomic_ops, optimize __atomic_set() for small values and
   __atomic_cmpxchg_bool() for compilers supporting flag output constraint
 
 - Couple of cleanups for KVM:
   - Move and improve KVM struct definitions for DAT tables from gaccess.c
     to a new header
   - Pass the asce as parameter to sie64a()
 
 - Make the crdte() and cspg() page table handling wrappers return a
   boolean to indicate success, like the other existing "compare and swap"
   wrappers
 
 - Add documentation for HWCAP flags
 
 - Switch to obtaining total RAM pages from memblock instead of
   totalram_pages() during mm init, to ensure correct calculation of zero
   page size, when defer_init is enabled
 
 - Refactor lowcore access and switch to using the get_lowcore() function
   instead of the S390_lowcore macro
 
 - Cleanups for PG_arch_1 and folio handling in UV and hugetlb code
 
 - Add missing MODULE_DESCRIPTION() macros
 
 - Fix VM_FAULT_HWPOISON handling in do_exception()
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCAAdFiEE3QHqV+H2a8xAv27vjYWKoQLXFBgFAmaYGegACgkQjYWKoQLX
 FBjCwwf/aRYoLIXCa9/nHGWFiUjZm6xBgVwZh55bXjfNG9TI2J9UZSsYlOFGUJKl
 gvD2Ym+LqAejK8R4EUHkfD6ftaKMQuIxNDoedxhwuSpfOQ2mZ5teu0MxTh8QcUAx
 4Y2w5XEeCuqE3SuoZ4SJa58K4rGl4cFpPsKNa8ofdzH1ZLFNe8Wqzis4kh0htqLb
 FtPj6nsgfzQ5kg14rVkGxCa4CqoFxonXgsA6nH6xZLbxKUInyq8uV44UBQ+aJq5v
 dsdzZ5XuAJHN2FpBuuOYQYZYw3XIy/kka7o4EjffORi5SGCRMWO4Zt0P6HXaNkh6
 xV8EEO8myeo7rV8dnrk1V4yGjGJmfA==
 =3IGY
 -----END PGP SIGNATURE-----

Merge tag 's390-6.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Remove restrictions on PAI NNPA and crypto counters, enabling
   concurrent per-task and system-wide sampling and counting events

 - Switch to GENERIC_CPU_DEVICES by setting up the CPU present mask in
   the architecture code and letting the generic code handle CPU
   bring-up

 - Add support for the diag204 busy indication facility to prevent
   undesirable blocking during hypervisor logical CPU utilization
   queries. Implement results caching

 - Improve the handling of Store Data SCLP events by suppressing
   unnecessary warning, preventing buffer release in I/O during
   failures, and adding timeout handling for Store Data requests to
   address potential firmware issues

 - Provide optimized __arch_hweight*() implementations

 - Remove the unnecessary CPU KOBJ_CHANGE uevents generated during
   topology updates, as they are unused and also not present on other
   architectures

 - Cleanup atomic_ops, optimize __atomic_set() for small values and
   __atomic_cmpxchg_bool() for compilers supporting flag output
   constraint

 - Couple of cleanups for KVM:
     - Move and improve KVM struct definitions for DAT tables from
       gaccess.c to a new header
     - Pass the asce as parameter to sie64a()

 - Make the crdte() and cspg() page table handling wrappers return a
   boolean to indicate success, like the other existing "compare and
   swap" wrappers

 - Add documentation for HWCAP flags

 - Switch to obtaining total RAM pages from memblock instead of
   totalram_pages() during mm init, to ensure correct calculation of
   zero page size, when defer_init is enabled

 - Refactor lowcore access and switch to using the get_lowcore()
   function instead of the S390_lowcore macro

 - Cleanups for PG_arch_1 and folio handling in UV and hugetlb code

 - Add missing MODULE_DESCRIPTION() macros

 - Fix VM_FAULT_HWPOISON handling in do_exception()

* tag 's390-6.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (54 commits)
  s390/mm: Fix VM_FAULT_HWPOISON handling in do_exception()
  s390/kvm: Move bitfields for dat tables
  s390/entry: Pass the asce as parameter to sie64a()
  s390/sthyi: Use cached data when diag is busy
  s390/sthyi: Move diag operations
  s390/hypfs_diag: Diag204 busy loop
  s390/diag: Add busy-indication-facility requirements
  s390/diag: Diag204 add busy return errno
  s390/diag: Return errno's from diag204
  s390/sclp: Diag204 busy indication facility detection
  s390/atomic_ops: Make use of flag output constraint
  s390/atomic_ops: Improve __atomic_set() for small values
  s390/atomic_ops: Use symbolic names
  s390/smp: Switch to GENERIC_CPU_DEVICES
  s390/hwcaps: Add documentation for HWCAP flags
  s390/pgtable: Make crdte() and cspg() return a value
  s390/topology: Remove CPU KOBJ_CHANGE uevents
  s390/sclp: Add timeout to Store Data requests
  s390/sclp: Prevent release of buffer in I/O
  s390/sclp: Suppress unnecessary Store Data warning
  ...
2024-07-18 15:41:45 -07:00
Paolo Bonzini
86014c1e20 KVM generic changes for 6.11
- Enable halt poll shrinking by default, as Intel found it to be a clear win.
 
  - Setup empty IRQ routing when creating a VM to avoid having to synchronize
    SRCU when creating a split IRQCHIP on x86.
 
  - Rework the sched_in/out() paths to replace kvm_arch_sched_in() with a flag
    that arch code can use for hooking both sched_in() and sched_out().
 
  - Take the vCPU @id as an "unsigned long" instead of "u32" to avoid
    truncating a bogus value from userspace, e.g. to help userspace detect bugs.
 
  - Mark a vCPU as preempted if and only if it's scheduled out while in the
    KVM_RUN loop, e.g. to avoid marking it preempted and thus writing guest
    memory when retrieving guest state during live migration blackout.
 
  - A few minor cleanups
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEKTobbabEP7vbhhN9OlYIJqCjN/0FAmaRuOYACgkQOlYIJqCj
 N/1UnQ/8CI5Qfr+/0gzYgtWmtEMczGG+rMNpzD3XVqPjJjXcMcBiQnplnzUVLhha
 vlPdYVK7vgmEt003XGzV55mik46LHL+DX/v4hI3HEdblfyCeNLW3fKEWVRB44qJe
 o+YUQwSK42SORUp9oXuQINxhA//U9EnI7CQxlJ8w8wenv5IJKfIGr01DefmfGPAV
 PKm9t6WLcNqvhZMEyy/zmzM3KVPCJL0NcwI97x6sHxFpQYIDtL0E/VexA4AFqMoT
 QK7cSDC/2US41Zvem/r/GzM/ucdF6vb9suzZYBohwhxtVhwJe2CDeYQZvtNKJ1U7
 GOHPaKL6nBWdZCm/yyWbbX2nstY1lHqxhN3JD0X8wqU5rNcwm2b8Vfyav0Ehc7H+
 jVbDTshOx4YJmIgajoKjgM050rdBK59TdfVL+l+AAV5q/TlHocalYtvkEBdGmIDg
 2td9UHSime6sp20vQfczUEz4bgrQsh4l2Fa/qU2jFwLievnBw0AvEaMximkSGMJe
 b8XfjmdTjlOesWAejANKtQolfrq14+1wYw0zZZ8PA+uNVpKdoovmcqSOcaDC9bT8
 GO/NFUvoG+lkcvJcIlo1SSl81SmGLosijwxWfGvFAqsgpR3/3l3dYp0QtztoCNJO
 d3+HnjgYn5o5FwufuTD3eUOXH4AFjG108DH0o25XrIkb2Kymy0o=
 =BalU
 -----END PGP SIGNATURE-----

Merge tag 'kvm-x86-generic-6.11' of https://github.com/kvm-x86/linux into HEAD

KVM generic changes for 6.11

 - Enable halt poll shrinking by default, as Intel found it to be a clear win.

 - Setup empty IRQ routing when creating a VM to avoid having to synchronize
   SRCU when creating a split IRQCHIP on x86.

 - Rework the sched_in/out() paths to replace kvm_arch_sched_in() with a flag
   that arch code can use for hooking both sched_in() and sched_out().

 - Take the vCPU @id as an "unsigned long" instead of "u32" to avoid
   truncating a bogus value from userspace, e.g. to help userspace detect bugs.

 - Mark a vCPU as preempted if and only if it's scheduled out while in the
   KVM_RUN loop, e.g. to avoid marking it preempted and thus writing guest
   memory when retrieving guest state during live migration blackout.

 - A few minor cleanups
2024-07-16 09:51:36 -04:00
Paolo Bonzini
c8b8b8190a LoongArch KVM changes for v6.11
1. Add ParaVirt steal time support.
 2. Add some VM migration enhancement.
 3. Add perf kvm-stat support for loongarch.
 -----BEGIN PGP SIGNATURE-----
 
 iQJKBAABCAA0FiEEzOlt8mkP+tbeiYy5AoYrw/LiJnoFAmaOS6UWHGNoZW5odWFj
 YWlAa2VybmVsLm9yZwAKCRAChivD8uImehejD/9pACGe3h3krXLcFVWXOFIu5Hpc
 5kQLP0lSPJ/o5Xs8t/oPLrnDX70z90wXI1LOmltc7h32MSwFa2l8COQh+sN5eJBQ
 PNyt7u7bMipp0yJS4Gl3LQQ5vklcGOSpQc/gbeXnVx8J/tz+Mo9YGGLIXVRXRM6W
 Ri8D2VVFiwzQQYeTpPo1u1Ob8C6mA4KOppwvhscMTM3vj4NMbsinBzRnR0lG0Tdw
 meFhxDPly1Ksxsbnj9UGO6UnEY0A2SLONs6MiO4y4DtoqoDlw/lbqFJuYo4vvbx1
 pxtjyirD/PX/wjslQFWUOuU0hMfAodera+JupZ5BZWfcG8FltA4DQfDsm/U9RjK/
 7gGNnr8Xk2/tp6+4AVV+HU2iTgRvq+mXCL72zSy2Y4r7ElBAANDfk4n+Zn/PWisn
 U9wwV8Ue7tVB15BRpRsg77NzBidiCFEe/6flWYiX2y24ke71gwDJBGUy8hMdKt6t
 4Cq8atsU0MvDAzfYMsK9JjskJp4UFq6wb1tXbbuADM4TDhnzlK6s6h3vM+pFlh/f
 my7fDH8/2qsCWhBDM4pmsJskVp+I1GOk/80RjTQISwx7iHktJWvxNYTaisK2fvD5
 Qs1IUWfNFbDX0Lr0QpN6j6X4rZkghR4R6XoFkd4nkicwi+UHVn3oK9GSqv24QJn9
 7+Ev3dfRTUYLd6mC4Q==
 =DpIK
 -----END PGP SIGNATURE-----

Merge tag 'loongarch-kvm-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson into HEAD

LoongArch KVM changes for v6.11

1. Add ParaVirt steal time support.
2. Add some VM migration enhancement.
3. Add perf kvm-stat support for loongarch.
2024-07-12 11:24:12 -04:00
Claudio Imbrenda
723ac2d6ba s390/entry: Pass the asce as parameter to sie64a()
Pass the guest ASCE explicitly as parameter, instead of having sie64a()
take it from lowcore.

This removes hidden state from lowcore, and makes things look cleaner.

Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Nico Boehr <nrb@linux.ibm.com>
Link: https://lore.kernel.org/r/20240703155900.103783-2-imbrenda@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2024-07-10 19:50:45 +02:00
Christoph Schlameuss
7816e58967 kvm: s390: Reject memory region operations for ucontrol VMs
This change rejects the KVM_SET_USER_MEMORY_REGION and
KVM_SET_USER_MEMORY_REGION2 ioctls when called on a ucontrol VM.
This is necessary since ucontrol VMs have kvm->arch.gmap set to 0 and
would thus result in a null pointer dereference further in.
Memory management needs to be performed in userspace and using the
ioctls KVM_S390_UCAS_MAP and KVM_S390_UCAS_UNMAP.

Also improve s390 specific documentation for KVM_SET_USER_MEMORY_REGION
and KVM_SET_USER_MEMORY_REGION2.

Signed-off-by: Christoph Schlameuss <schlameuss@linux.ibm.com>
Fixes: 27e0393f15 ("KVM: s390: ucontrol: per vcpu address spaces")
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20240624095902.29375-1-schlameuss@linux.ibm.com
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
[frankja@linux.ibm.com: commit message spelling fix, subject prefix fix]
Message-ID: <20240624095902.29375-1-schlameuss@linux.ibm.com>
2024-07-04 09:07:24 +02:00
Christian Borntraeger
4c6abb7f7b KVM: s390: fix LPSWEY handling
in rare cases, e.g. for injecting a machine check we do intercept all
load PSW instructions via ICTL_LPSW. With facility 193 a new variant
LPSWEY was added. KVM needs to handle that as well.

Fixes: a3efa84292 ("KVM: s390: gen_facilities: allow facilities 165, 193, 194 and 196")
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Message-ID: <20240628163547.2314-1-borntraeger@linux.ibm.com>
2024-07-01 14:31:15 +02:00
David Matlack
a6816314af KVM: Introduce vcpu->wants_to_run
Introduce vcpu->wants_to_run to indicate when a vCPU is in its core run
loop, i.e. when the vCPU is running the KVM_RUN ioctl and immediate_exit
was not set.

Replace all references to vcpu->run->immediate_exit with
!vcpu->wants_to_run to avoid TOCTOU races with userspace. For example, a
malicious userspace could invoked KVM_RUN with immediate_exit=true and
then after KVM reads it to set wants_to_run=false, flip it to false.
This would result in the vCPU running in KVM_RUN with
wants_to_run=false. This wouldn't cause any real bugs today but is a
dangerous landmine.

Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20240503181734.1467938-2-dmatlack@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-06-18 09:20:01 -07:00
Sven Schnelle
208da1d5fc s390: Replace S390_lowcore by get_lowcore()
Replace all S390_lowcore usages in arch/s390/ by get_lowcore().

Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2024-06-18 17:01:33 +02:00
Yi Wang
c4201bd24f KVM: s390: Don't re-setup dummy routing when KVM_CREATE_IRQCHIP
Now that KVM sets up empty irq routing in kvm_create_vm(), there's
no need to setup dummy routing when KVM_CREATE_IRQCHIP.

Note, userspace could very theoretically use KVM_CREATE_IRQCHIP after
KVM_SET_GSI_ROUTING to reset to empty IRQ routing, but it's extremely
unlikely any VMM does that, e.g. the main reason s390 does anything for
KVM_CREATE_IRQCHIP is to that s390 doesn't need to be special cased by the
VMM.

Signed-off-by: Yi Wang <foxywang@tencent.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Link: https://lore.kernel.org/r/20240506101751.3145407-4-foxywang@tencent.com
[sean: keep use_irqchip check, call out KVM_SET_GSI_ROUTING impact]
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-06-11 14:18:41 -07:00
Linus Torvalds
d65e1a0f30 - Store AP Query Configuration Information in a static buffer
- Rework the AP initialization and add missing cleanups to the error path
 
 - Swap IRQ and AP bus/device registration to avoid race conditions
 
 - Export prot_virt_guest symbol
 
 - Introduce AP configuration changes notifier interface to facilitate
   modularization of the AP bus
 
 - Add CONFIG_AP kernel configuration option to allow modularization of
   the AP bus
 
 - Rework CONFIG_ZCRYPT_DEBUG kernel configuration option description and
   dependency and rename it to CONFIG_AP_DEBUG
 
 - Convert sprintf() and snprintf() to sysfs_emit() in CIO code
 
 - Adjust indentation of RELOCS command build step
 
 - Make crypto performance counters upward compatible
 
 - Convert make_page_secure() and gmap_make_secure() to use folio
 
 - Rework channel-utilization-block (CUB) handling in preparation of
   introducing additional CUBs
 
 - Use attribute groups to simplify registration, removal and extension
   of measurement-related channel-path sysfs attributes
 
 - Add a per-channel-path binary "ext_measurement" sysfs attribute that
   provides access to extended channel-path measurement data
 
 - Export measurement data for all channel-measurement-groups (CMG), not
   only for a specific ones. This enables support of new CMG data formats
   in userspace without the need for kernel changes
 
 - Add a per-channel-path sysfs attribute "speed_bps" that provides the
   operating speed in bits per second or 0 if the operating speed is not
   available
 
 - The CIO tracepoint subchannel-type field "st" is incorrectly set to
   the value of subchannel-enabled SCHIB "ena" field. Fix that
 
 - Do not forcefully limit vmemmap starting address to MAX_PHYSMEM_BITS
 
 - Consider the maximum physical address available to a DCSS segment
   (512GB) when memory layout is set up
 
 - Simplify the virtual memory layout setup by reducing the size of
   identity mapping vs vmemmap overlap
 
 - Swap vmalloc and Lowcore/Real Memory Copy areas in virtual memory.
   This will allow to place the kernel image next to kernel modules
 
 - Move everyting KASLR related from <asm/setup.h> to <asm/page.h>
 
 - Put virtual memory layout information into a structure to improve
   code generation
 
 - Currently __kaslr_offset is the kernel offset in both physical and
   virtual memory spaces. Uncouple these offsets to allow uncoupling
   of the addresses spaces
 
 - Currently the identity mapping base address is implicit and is always
   set to zero. Make it explicit by putting into __identity_base persistent
   boot variable and use it in proper context
 
 - Introduce .amode31 section start and end macros AMODE31_START and
   AMODE31_END
 
 - Introduce OS_INFO entries that do not reference any data in memory,
   but rather provide only values
 
 - Store virtual memory layout in OS_INFO. It is read out by makedumpfile,
   crash and other tools
 
 - Store virtual memory layout in VMCORE_INFO. It is read out by crash and
   other tools when /proc/kcore device is used
 
 - Create additional PT_LOAD ELF program header that covers kernel image
   only, so that vmcore tools could locate kernel text and data when virtual
   and physical memory spaces are uncoupled
 
 - Uncouple physical and virtual address spaces
 
 - Map kernel at fixed location when KASLR mode is disabled. The location is
   defined by CONFIG_KERNEL_IMAGE_BASE kernel configuration value.
 
 - Rework deployment of kernel image for both compressed and uncompressed
   variants as defined by CONFIG_KERNEL_UNCOMPRESSED kernel configuration
   value
 
 - Move .vmlinux.relocs section in front of the compressed kernel.
   The interim section rescue step is avoided as result
 
 - Correct modules thunk offset calculation when branch target is more
   than 2GB away
 
 - Kernel modules contain their own set of expoline thunks. Now that the
   kernel modules area is less than 4GB away from kernel expoline thunks,
   make modules use kernel expolines. Also make EXPOLINE_EXTERN the default
   if the compiler supports it
 
 - userfaultfd can insert shared zeropages into processes running VMs,
   but that is not allowed for s390. Fallback to allocating a fresh
   zeroed anonymous folio and insert that instead
 
 - Re-enable shared zeropages for non-PV and non-skeys KVM guests
 
 - Rename hex2bitmap() to ap_hex2bitmap() and export it for external use
 
 - Add ap_config sysfs attribute to provide the means for setting or
   displaying adapters, domains and control domains assigned to a vfio-ap
   mediated device in a single operation
 
 - Make vfio_ap_mdev_link_queue() ignore duplicate link requests
 
 - Add write support to ap_config sysfs attribute to allow atomic update
   a vfio-ap mediated device state
 
 - Document ap_config sysfs attribute
 
 - Function os_info_old_init() is expected to be called only from a regular
   kdump kernel. Enable it to be called from a stand-alone dump kernel
 
 - Address gcc -Warray-bounds warning and fix array size in struct os_info
 
 - s390 does not support SMBIOS, so drop unneeded CONFIG_DMI checks
 
 - Use unwinder instead of __builtin_return_address() with ftrace to
   prevent returning of undefined values
 
 - Sections .hash and .gnu.hash are only created when CONFIG_PIE_BUILD
   kernel is enabled. Drop these for the case CONFIG_PIE_BUILD is disabled
 
 - Compile kernel with -fPIC and link with -no-pie to allow kpatch feature
   always succeed and drop the whole CONFIG_PIE_BUILD option-enabled code
 
 - Add missing virt_to_phys() converter for VSIE facility and crypto
   control blocks
 -----BEGIN PGP SIGNATURE-----
 
 iI0EABYIADUWIQQrtrZiYVkVzKQcYivNdxKlNrRb8AUCZjkp5xccYWdvcmRlZXZA
 bGludXguaWJtLmNvbQAKCRDNdxKlNrRb8D99AQCEby+KHssuZe9m0NvvikWREYBC
 myqob4EmdU3KdTEbNAEAt2OB7mzSQc90yjawI+Je7vwVyh3uc2Nb4Qg05yO6owI=
 =eOYN
 -----END PGP SIGNATURE-----

Merge tag 's390-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Alexander Gordeev:

 - Store AP Query Configuration Information in a static buffer

 - Rework the AP initialization and add missing cleanups to the error
   path

 - Swap IRQ and AP bus/device registration to avoid race conditions

 - Export prot_virt_guest symbol

 - Introduce AP configuration changes notifier interface to facilitate
   modularization of the AP bus

 - Add CONFIG_AP kernel configuration option to allow modularization of
   the AP bus

 - Rework CONFIG_ZCRYPT_DEBUG kernel configuration option description
   and dependency and rename it to CONFIG_AP_DEBUG

 - Convert sprintf() and snprintf() to sysfs_emit() in CIO code

 - Adjust indentation of RELOCS command build step

 - Make crypto performance counters upward compatible

 - Convert make_page_secure() and gmap_make_secure() to use folio

 - Rework channel-utilization-block (CUB) handling in preparation of
   introducing additional CUBs

 - Use attribute groups to simplify registration, removal and extension
   of measurement-related channel-path sysfs attributes

 - Add a per-channel-path binary "ext_measurement" sysfs attribute that
   provides access to extended channel-path measurement data

 - Export measurement data for all channel-measurement-groups (CMG), not
   only for a specific ones. This enables support of new CMG data
   formats in userspace without the need for kernel changes

 - Add a per-channel-path sysfs attribute "speed_bps" that provides the
   operating speed in bits per second or 0 if the operating speed is not
   available

 - The CIO tracepoint subchannel-type field "st" is incorrectly set to
   the value of subchannel-enabled SCHIB "ena" field. Fix that

 - Do not forcefully limit vmemmap starting address to MAX_PHYSMEM_BITS

 - Consider the maximum physical address available to a DCSS segment
   (512GB) when memory layout is set up

 - Simplify the virtual memory layout setup by reducing the size of
   identity mapping vs vmemmap overlap

 - Swap vmalloc and Lowcore/Real Memory Copy areas in virtual memory.
   This will allow to place the kernel image next to kernel modules

 - Move everyting KASLR related from <asm/setup.h> to <asm/page.h>

 - Put virtual memory layout information into a structure to improve
   code generation

 - Currently __kaslr_offset is the kernel offset in both physical and
   virtual memory spaces. Uncouple these offsets to allow uncoupling of
   the addresses spaces

 - Currently the identity mapping base address is implicit and is always
   set to zero. Make it explicit by putting into __identity_base
   persistent boot variable and use it in proper context

 - Introduce .amode31 section start and end macros AMODE31_START and
   AMODE31_END

 - Introduce OS_INFO entries that do not reference any data in memory,
   but rather provide only values

 - Store virtual memory layout in OS_INFO. It is read out by
   makedumpfile, crash and other tools

 - Store virtual memory layout in VMCORE_INFO. It is read out by crash
   and other tools when /proc/kcore device is used

 - Create additional PT_LOAD ELF program header that covers kernel image
   only, so that vmcore tools could locate kernel text and data when
   virtual and physical memory spaces are uncoupled

 - Uncouple physical and virtual address spaces

 - Map kernel at fixed location when KASLR mode is disabled. The
   location is defined by CONFIG_KERNEL_IMAGE_BASE kernel configuration
   value.

 - Rework deployment of kernel image for both compressed and
   uncompressed variants as defined by CONFIG_KERNEL_UNCOMPRESSED kernel
   configuration value

 - Move .vmlinux.relocs section in front of the compressed kernel. The
   interim section rescue step is avoided as result

 - Correct modules thunk offset calculation when branch target is more
   than 2GB away

 - Kernel modules contain their own set of expoline thunks. Now that the
   kernel modules area is less than 4GB away from kernel expoline
   thunks, make modules use kernel expolines. Also make EXPOLINE_EXTERN
   the default if the compiler supports it

 - userfaultfd can insert shared zeropages into processes running VMs,
   but that is not allowed for s390. Fallback to allocating a fresh
   zeroed anonymous folio and insert that instead

 - Re-enable shared zeropages for non-PV and non-skeys KVM guests

 - Rename hex2bitmap() to ap_hex2bitmap() and export it for external use

 - Add ap_config sysfs attribute to provide the means for setting or
   displaying adapters, domains and control domains assigned to a
   vfio-ap mediated device in a single operation

 - Make vfio_ap_mdev_link_queue() ignore duplicate link requests

 - Add write support to ap_config sysfs attribute to allow atomic update
   a vfio-ap mediated device state

 - Document ap_config sysfs attribute

 - Function os_info_old_init() is expected to be called only from a
   regular kdump kernel. Enable it to be called from a stand-alone dump
   kernel

 - Address gcc -Warray-bounds warning and fix array size in struct
   os_info

 - s390 does not support SMBIOS, so drop unneeded CONFIG_DMI checks

 - Use unwinder instead of __builtin_return_address() with ftrace to
   prevent returning of undefined values

 - Sections .hash and .gnu.hash are only created when CONFIG_PIE_BUILD
   kernel is enabled. Drop these for the case CONFIG_PIE_BUILD is
   disabled

 - Compile kernel with -fPIC and link with -no-pie to allow kpatch
   feature always succeed and drop the whole CONFIG_PIE_BUILD
   option-enabled code

 - Add missing virt_to_phys() converter for VSIE facility and crypto
   control blocks

* tag 's390-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (54 commits)
  Revert "s390: Relocate vmlinux ELF data to virtual address space"
  KVM: s390: vsie: Use virt_to_phys for crypto control block
  s390: Relocate vmlinux ELF data to virtual address space
  s390: Compile kernel with -fPIC and link with -no-pie
  s390: vmlinux.lds.S: Drop .hash and .gnu.hash for !CONFIG_PIE_BUILD
  s390/ftrace: Use unwinder instead of __builtin_return_address()
  s390/pci: Drop unneeded reference to CONFIG_DMI
  s390/os_info: Fix array size in struct os_info
  s390/os_info: Initialize old os_info in standalone dump kernel
  docs: Update s390 vfio-ap doc for ap_config sysfs attribute
  s390/vfio-ap: Add write support to sysfs attr ap_config
  s390/vfio-ap: Ignore duplicate link requests in vfio_ap_mdev_link_queue
  s390/vfio-ap: Add sysfs attr, ap_config, to export mdev state
  s390/ap: Externalize AP bus specific bitmap reading function
  s390/mm: Re-enable the shared zeropage for !PV and !skeys KVM guests
  mm/userfaultfd: Do not place zeropages when zeropages are disallowed
  s390/expoline: Make modules use kernel expolines
  s390/nospec: Correct modules thunk offset calculation
  s390/boot: Do not rescue .vmlinux.relocs section
  s390/boot: Rework deployment of the kernel image
  ...
2024-05-13 08:33:52 -07:00
Jean-Philippe Brucker
175f2f5bcd KVM: s390: Check kvm pointer when testing KVM_CAP_S390_HPAGE_1M
KVM allows issuing the KVM_CHECK_EXTENSION ioctl either on the /dev/kvm
fd or the VM fd. In the first case, kvm_vm_ioctl_check_extension() is
called with kvm==NULL. Ensure we don't dereference the pointer in that
case.

Fixes: 40ebdb8e59 ("KVM: s390: Make huge pages unavailable in ucontrol VMs")
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Message-ID: <20240419160723.320910-2-jean-philippe@linaro.org>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2024-05-02 09:41:38 +02:00
David Hildenbrand
06201e00ee s390/mm: Re-enable the shared zeropage for !PV and !skeys KVM guests
commit fa41ba0d08 ("s390/mm: avoid empty zero pages for KVM guests to
avoid postcopy hangs") introduced an undesired side effect when combined
with memory ballooning and VM migration: memory part of the inflated
memory balloon will consume memory.

Assuming we have a 100GiB VM and inflated the balloon to 40GiB. Our VM
will consume ~60GiB of memory. If we now trigger a VM migration,
hypervisors like QEMU will read all VM memory. As s390x does not support
the shared zeropage, we'll end up allocating for all previously-inflated
memory part of the memory balloon: 50 GiB. So we might easily
(unexpectedly) crash the VM on the migration source.

Even worse, hypervisors like QEMU optimize for zeropage migration to not
consume memory on the migration destination: when migrating a
"page full of zeroes", on the migration destination they check whether the
target memory is already zero (by reading the destination memory) and avoid
writing to the memory to not allocate memory: however, s390x will also
allocate memory here, implying that also on the migration destination, we
will end up allocating all previously-inflated memory part of the memory
balloon.

This is especially bad if actual memory overcommit was not desired, when
memory ballooning is used for dynamic VM memory resizing, setting aside
some memory during boot that can be added later on demand. Alternatives
like virtio-mem that would avoid this issue are not yet available on
s390x.

There could be ways to optimize some cases in user space: before reading
memory in an anonymous private mapping on the migration source, check via
/proc/self/pagemap if anything is already populated. Similarly check on
the migration destination before reading. While that would avoid
populating tables full of shared zeropages on all architectures, it's
harder to get right and performant, and requires user space changes.

Further, with posctopy live migration we must place a page, so there,
"avoid touching memory to avoid allocating memory" is not really
possible. (Note that a previously we would have falsely inserted
shared zeropages into processes using UFFDIO_ZEROPAGE where
mm_forbids_zeropage() would have actually forbidden it)

PV is currently incompatible with memory ballooning, and in the common
case, KVM guests don't make use of storage keys. Instead of zapping
zeropages when enabling storage keys / PV, that turned out to be
problematic in the past, let's do exactly the same we do with KSM pages:
trigger unsharing faults to replace the shared zeropages by proper
anonymous folios.

What about added latency when enabling storage kes? Having a lot of
zeropages in applicable environments (PV, legacy guests, unittests) is
unexpected. Further, KSM could today already unshare the zeropages
and unmerging KSM pages when enabling storage kets would unshare the
KSM-placed zeropages in the same way, resulting in the same latency.

[ agordeev: Fixed sparse and checkpatch complaints and error handling ]

Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Tested-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Fixes: fa41ba0d08 ("s390/mm: avoid empty zero pages for KVM guests to avoid postcopy hangs")
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20240411161441.910170-3-david@redhat.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2024-04-18 15:02:53 +02:00
Linus Torvalds
4f712ee0cb S390:
* Changes to FPU handling came in via the main s390 pull request
 
 * Only deliver to the guest the SCLP events that userspace has
   requested.
 
 * More virtual vs physical address fixes (only a cleanup since
   virtual and physical address spaces are currently the same).
 
 * Fix selftests undefined behavior.
 
 x86:
 
 * Fix a restriction that the guest can't program a PMU event whose
   encoding matches an architectural event that isn't included in the
   guest CPUID.  The enumeration of an architectural event only says
   that if a CPU supports an architectural event, then the event can be
   programmed *using the architectural encoding*.  The enumeration does
   NOT say anything about the encoding when the CPU doesn't report support
   the event *in general*.  It might support it, and it might support it
   using the same encoding that made it into the architectural PMU spec.
 
 * Fix a variety of bugs in KVM's emulation of RDPMC (more details on
   individual commits) and add a selftest to verify KVM correctly emulates
   RDMPC, counter availability, and a variety of other PMC-related
   behaviors that depend on guest CPUID and therefore are easier to
   validate with selftests than with custom guests (aka kvm-unit-tests).
 
 * Zero out PMU state on AMD if the virtual PMU is disabled, it does not
   cause any bug but it wastes time in various cases where KVM would check
   if a PMC event needs to be synthesized.
 
 * Optimize triggering of emulated events, with a nice ~10% performance
   improvement in VM-Exit microbenchmarks when a vPMU is exposed to the
   guest.
 
 * Tighten the check for "PMI in guest" to reduce false positives if an NMI
   arrives in the host while KVM is handling an IRQ VM-Exit.
 
 * Fix a bug where KVM would report stale/bogus exit qualification information
   when exiting to userspace with an internal error exit code.
 
 * Add a VMX flag in /proc/cpuinfo to report 5-level EPT support.
 
 * Rework TDP MMU root unload, free, and alloc to run with mmu_lock held for
   read, e.g. to avoid serializing vCPUs when userspace deletes a memslot.
 
 * Tear down TDP MMU page tables at 4KiB granularity (used to be 1GiB).  KVM
   doesn't support yielding in the middle of processing a zap, and 1GiB
   granularity resulted in multi-millisecond lags that are quite impolite
   for CONFIG_PREEMPT kernels.
 
 * Allocate write-tracking metadata on-demand to avoid the memory overhead when
   a kernel is built with i915 virtualization support but the workloads use
   neither shadow paging nor i915 virtualization.
 
 * Explicitly initialize a variety of on-stack variables in the emulator that
   triggered KMSAN false positives.
 
 * Fix the debugregs ABI for 32-bit KVM.
 
 * Rework the "force immediate exit" code so that vendor code ultimately decides
   how and when to force the exit, which allowed some optimization for both
   Intel and AMD.
 
 * Fix a long-standing bug where kvm_has_noapic_vcpu could be left elevated if
   vCPU creation ultimately failed, causing extra unnecessary work.
 
 * Cleanup the logic for checking if the currently loaded vCPU is in-kernel.
 
 * Harden against underflowing the active mmu_notifier invalidation
   count, so that "bad" invalidations (usually due to bugs elsehwere in the
   kernel) are detected earlier and are less likely to hang the kernel.
 
 x86 Xen emulation:
 
 * Overlay pages can now be cached based on host virtual address,
   instead of guest physical addresses.  This removes the need to
   reconfigure and invalidate the cache if the guest changes the
   gpa but the underlying host virtual address remains the same.
 
 * When possible, use a single host TSC value when computing the deadline for
   Xen timers in order to improve the accuracy of the timer emulation.
 
 * Inject pending upcall events when the vCPU software-enables its APIC to fix
   a bug where an upcall can be lost (and to follow Xen's behavior).
 
 * Fall back to the slow path instead of warning if "fast" IRQ delivery of Xen
   events fails, e.g. if the guest has aliased xAPIC IDs.
 
 RISC-V:
 
 * Support exception and interrupt handling in selftests
 
 * New self test for RISC-V architectural timer (Sstc extension)
 
 * New extension support (Ztso, Zacas)
 
 * Support userspace emulation of random number seed CSRs.
 
 ARM:
 
 * Infrastructure for building KVM's trap configuration based on the
   architectural features (or lack thereof) advertised in the VM's ID
   registers
 
 * Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to
   x86's WC) at stage-2, improving the performance of interacting with
   assigned devices that can tolerate it
 
 * Conversion of KVM's representation of LPIs to an xarray, utilized to
   address serialization some of the serialization on the LPI injection
   path
 
 * Support for _architectural_ VHE-only systems, advertised through the
   absence of FEAT_E2H0 in the CPU's ID register
 
 * Miscellaneous cleanups, fixes, and spelling corrections to KVM and
   selftests
 
 LoongArch:
 
 * Set reserved bits as zero in CPUCFG.
 
 * Start SW timer only when vcpu is blocking.
 
 * Do not restart SW timer when it is expired.
 
 * Remove unnecessary CSR register saving during enter guest.
 
 * Misc cleanups and fixes as usual.
 
 Generic:
 
 * cleanup Kconfig by removing CONFIG_HAVE_KVM, which was basically always
   true on all architectures except MIPS (where Kconfig determines the
   available depending on CPU capabilities).  It is replaced either by
   an architecture-dependent symbol for MIPS, and IS_ENABLED(CONFIG_KVM)
   everywhere else.
 
 * Factor common "select" statements in common code instead of requiring
   each architecture to specify it
 
 * Remove thoroughly obsolete APIs from the uapi headers.
 
 * Move architecture-dependent stuff to uapi/asm/kvm.h
 
 * Always flush the async page fault workqueue when a work item is being
   removed, especially during vCPU destruction, to ensure that there are no
   workers running in KVM code when all references to KVM-the-module are gone,
   i.e. to prevent a very unlikely use-after-free if kvm.ko is unloaded.
 
 * Grab a reference to the VM's mm_struct in the async #PF worker itself instead
   of gifting the worker a reference, so that there's no need to remember
   to *conditionally* clean up after the worker.
 
 Selftests:
 
 * Reduce boilerplate especially when utilize selftest TAP infrastructure.
 
 * Add basic smoke tests for SEV and SEV-ES, along with a pile of library
   support for handling private/encrypted/protected memory.
 
 * Fix benign bugs where tests neglect to close() guest_memfd files.
 -----BEGIN PGP SIGNATURE-----
 
 iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmX0iP8UHHBib256aW5p
 QHJlZGhhdC5jb20ACgkQv/vSX3jHroND7wf+JZoNvwZ+bmwWe/4jn/YwNoYi/C5z
 eypn8M1gsWEccpCpqPBwznVm9T29rF4uOlcMvqLEkHfTpaL1EKUUjP1lXPz/ileP
 6a2RdOGxAhyTiFC9fjy+wkkjtLbn1kZf6YsS0hjphP9+w0chNbdn0w81dFVnXryd
 j7XYI8R/bFAthNsJOuZXSEjCfIHxvTTG74OrTf1B1FEBB+arPmrgUeJftMVhffQK
 Sowgg8L/Ii/x6fgV5NZQVSIyVf1rp8z7c6UaHT4Fwb0+RAMW8p9pYv9Qp1YkKp8y
 5j0V9UzOHP7FRaYimZ5BtwQoqiZXYylQ+VuU/Y2f4X85cvlLzSqxaEMAPA==
 =mqOV
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "S390:

   - Changes to FPU handling came in via the main s390 pull request

   - Only deliver to the guest the SCLP events that userspace has
     requested

   - More virtual vs physical address fixes (only a cleanup since
     virtual and physical address spaces are currently the same)

   - Fix selftests undefined behavior

  x86:

   - Fix a restriction that the guest can't program a PMU event whose
     encoding matches an architectural event that isn't included in the
     guest CPUID. The enumeration of an architectural event only says
     that if a CPU supports an architectural event, then the event can
     be programmed *using the architectural encoding*. The enumeration
     does NOT say anything about the encoding when the CPU doesn't
     report support the event *in general*. It might support it, and it
     might support it using the same encoding that made it into the
     architectural PMU spec

   - Fix a variety of bugs in KVM's emulation of RDPMC (more details on
     individual commits) and add a selftest to verify KVM correctly
     emulates RDMPC, counter availability, and a variety of other
     PMC-related behaviors that depend on guest CPUID and therefore are
     easier to validate with selftests than with custom guests (aka
     kvm-unit-tests)

   - Zero out PMU state on AMD if the virtual PMU is disabled, it does
     not cause any bug but it wastes time in various cases where KVM
     would check if a PMC event needs to be synthesized

   - Optimize triggering of emulated events, with a nice ~10%
     performance improvement in VM-Exit microbenchmarks when a vPMU is
     exposed to the guest

   - Tighten the check for "PMI in guest" to reduce false positives if
     an NMI arrives in the host while KVM is handling an IRQ VM-Exit

   - Fix a bug where KVM would report stale/bogus exit qualification
     information when exiting to userspace with an internal error exit
     code

   - Add a VMX flag in /proc/cpuinfo to report 5-level EPT support

   - Rework TDP MMU root unload, free, and alloc to run with mmu_lock
     held for read, e.g. to avoid serializing vCPUs when userspace
     deletes a memslot

   - Tear down TDP MMU page tables at 4KiB granularity (used to be
     1GiB). KVM doesn't support yielding in the middle of processing a
     zap, and 1GiB granularity resulted in multi-millisecond lags that
     are quite impolite for CONFIG_PREEMPT kernels

   - Allocate write-tracking metadata on-demand to avoid the memory
     overhead when a kernel is built with i915 virtualization support
     but the workloads use neither shadow paging nor i915 virtualization

   - Explicitly initialize a variety of on-stack variables in the
     emulator that triggered KMSAN false positives

   - Fix the debugregs ABI for 32-bit KVM

   - Rework the "force immediate exit" code so that vendor code
     ultimately decides how and when to force the exit, which allowed
     some optimization for both Intel and AMD

   - Fix a long-standing bug where kvm_has_noapic_vcpu could be left
     elevated if vCPU creation ultimately failed, causing extra
     unnecessary work

   - Cleanup the logic for checking if the currently loaded vCPU is
     in-kernel

   - Harden against underflowing the active mmu_notifier invalidation
     count, so that "bad" invalidations (usually due to bugs elsehwere
     in the kernel) are detected earlier and are less likely to hang the
     kernel

  x86 Xen emulation:

   - Overlay pages can now be cached based on host virtual address,
     instead of guest physical addresses. This removes the need to
     reconfigure and invalidate the cache if the guest changes the gpa
     but the underlying host virtual address remains the same

   - When possible, use a single host TSC value when computing the
     deadline for Xen timers in order to improve the accuracy of the
     timer emulation

   - Inject pending upcall events when the vCPU software-enables its
     APIC to fix a bug where an upcall can be lost (and to follow Xen's
     behavior)

   - Fall back to the slow path instead of warning if "fast" IRQ
     delivery of Xen events fails, e.g. if the guest has aliased xAPIC
     IDs

  RISC-V:

   - Support exception and interrupt handling in selftests

   - New self test for RISC-V architectural timer (Sstc extension)

   - New extension support (Ztso, Zacas)

   - Support userspace emulation of random number seed CSRs

  ARM:

   - Infrastructure for building KVM's trap configuration based on the
     architectural features (or lack thereof) advertised in the VM's ID
     registers

   - Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to
     x86's WC) at stage-2, improving the performance of interacting with
     assigned devices that can tolerate it

   - Conversion of KVM's representation of LPIs to an xarray, utilized
     to address serialization some of the serialization on the LPI
     injection path

   - Support for _architectural_ VHE-only systems, advertised through
     the absence of FEAT_E2H0 in the CPU's ID register

   - Miscellaneous cleanups, fixes, and spelling corrections to KVM and
     selftests

  LoongArch:

   - Set reserved bits as zero in CPUCFG

   - Start SW timer only when vcpu is blocking

   - Do not restart SW timer when it is expired

   - Remove unnecessary CSR register saving during enter guest

   - Misc cleanups and fixes as usual

  Generic:

   - Clean up Kconfig by removing CONFIG_HAVE_KVM, which was basically
     always true on all architectures except MIPS (where Kconfig
     determines the available depending on CPU capabilities). It is
     replaced either by an architecture-dependent symbol for MIPS, and
     IS_ENABLED(CONFIG_KVM) everywhere else

   - Factor common "select" statements in common code instead of
     requiring each architecture to specify it

   - Remove thoroughly obsolete APIs from the uapi headers

   - Move architecture-dependent stuff to uapi/asm/kvm.h

   - Always flush the async page fault workqueue when a work item is
     being removed, especially during vCPU destruction, to ensure that
     there are no workers running in KVM code when all references to
     KVM-the-module are gone, i.e. to prevent a very unlikely
     use-after-free if kvm.ko is unloaded

   - Grab a reference to the VM's mm_struct in the async #PF worker
     itself instead of gifting the worker a reference, so that there's
     no need to remember to *conditionally* clean up after the worker

  Selftests:

   - Reduce boilerplate especially when utilize selftest TAP
     infrastructure

   - Add basic smoke tests for SEV and SEV-ES, along with a pile of
     library support for handling private/encrypted/protected memory

   - Fix benign bugs where tests neglect to close() guest_memfd files"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (246 commits)
  selftests: kvm: remove meaningless assignments in Makefiles
  KVM: riscv: selftests: Add Zacas extension to get-reg-list test
  RISC-V: KVM: Allow Zacas extension for Guest/VM
  KVM: riscv: selftests: Add Ztso extension to get-reg-list test
  RISC-V: KVM: Allow Ztso extension for Guest/VM
  RISC-V: KVM: Forward SEED CSR access to user space
  KVM: riscv: selftests: Add sstc timer test
  KVM: riscv: selftests: Change vcpu_has_ext to a common function
  KVM: riscv: selftests: Add guest helper to get vcpu id
  KVM: riscv: selftests: Add exception handling support
  LoongArch: KVM: Remove unnecessary CSR register saving during enter guest
  LoongArch: KVM: Do not restart SW timer when it is expired
  LoongArch: KVM: Start SW timer only when vcpu is blocking
  LoongArch: KVM: Set reserved bits as zero in CPUCFG
  KVM: selftests: Explicitly close guest_memfd files in some gmem tests
  KVM: x86/xen: fix recursive deadlock in timer injection
  KVM: pfncache: simplify locking and make more self-contained
  KVM: x86/xen: remove WARN_ON_ONCE() with false positives in evtchn delivery
  KVM: x86/xen: inject vCPU upcall vector when local APIC is enabled
  KVM: x86/xen: improve accuracy of Xen timers
  ...
2024-03-15 13:03:13 -07:00
Paolo Bonzini
17193ced2d - Memop selftest rotate fix
- SCLP event bits over indication fix
 - Missing virt_to_phys for the CRYCB fix
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEwGNS88vfc9+v45Yq41TmuOI4ufgFAmXcfYoACgkQ41TmuOI4
 ufhPExAAxdcg3WjnTe/EYe+GnyjKo3nZs4y9dhZk9gf06qEYEawhg0ug5akzRZIH
 SDKeFqOXzl/ZRuL5hvfYBzxpy+IR3rWAYhBKUyxR6aJBl+RZKlf+Xn7l8iIKbNDq
 vAtLh9Hqza5IJiw/jtorw90TmiHDKvMlvft4UMG3t1IppyktUuuH0aujaVpeKtMR
 8qVyGsaTmNHip6Pi7w3WUnvYPkMNLoM7UIPhBAvWrJyYrLxao8pKEGWHaKwbMNHL
 Om4bjykfFCZ1Cs9aLZDLEasuD61Fpp41DnvImYm77yuDOdI4WalIlV7F5NbjQhhd
 IrQdsmlZc+N+HKcYvia6MnzAChTpo25pynvW7xXFQIfl/9VxcMFAfSLqLZMGMKFC
 IwzwI+BA3+bgw6zbN2z2uBShIom7Zzr689U8mbt5q7JborOH38qd5+IX6QFwUtTv
 IPHrgcULdWHWT5TRaIp61cB9YzCx2YU1QrMWEUVehldQqGEt8ANdZU5Ov0KG1BVl
 L9ULBIEnJ2ib1pGA7Xlxl2U0Lr2w/dg/p7EAdnOGes50GfEwEjtBzb7VO9Xfrz/Z
 j927hQO354Y8OYRFjKDjTceENynCiYsbNEhTHE6qFRIwAmeSVk4PT+vIXO6wZlZi
 Ee3LxsvVUnhYuC7sZbBUNhyiEjNn6GG3LxAtPeDoD+HvhqXI2Qg=
 =bwck
 -----END PGP SIGNATURE-----

Merge tag 'kvm-s390-next-6.9-1' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

- Memop selftest rotate fix
- SCLP event bits over indication fix
- Missing virt_to_phys for the CRYCB fix
2024-03-14 14:47:56 -04:00
Eric Farman
01be7f53df KVM: s390: fix access register usage in ioctls
The routine ar_translation() can be reached by both the instruction
intercept path (where the access registers had been loaded with the
guest register contents), and the MEM_OP ioctls (which hadn't).
Since this routine saves the current registers to vcpu->run,
this routine erroneously saves host registers into the guest space.

Introduce a boolean in the kvm_vcpu_arch struct to indicate whether
the registers contain guest contents. If they do (the instruction
intercept path), the save can be performed and the AR translation
is done just as it is today. If they don't (the MEM_OP path), the
AR can be read from vcpu->run without stashing the current contents.

Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Link: https://lore.kernel.org/r/20240220211211.3102609-2-farman@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-02-22 16:06:56 +01:00
Janosch Frank
4a59932874 KVM: s390: introduce kvm_s390_fpu_(store|load)
It's a bit nicer than having multiple lines and will help if there's
another re-work since we'll only have to change one location.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-02-21 15:09:13 +01:00