mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
synced 2025-09-07 22:23:00 +00:00
loongarch-next
1119 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Paolo Bonzini
|
d7f4aac280 |
Merge tag 'kvm-x86-mmu-6.17' of https://github.com/kvm-x86/linux into HEAD
KVM x86 MMU changes for 6.17 - Exempt nested EPT from the the !USER + CR0.WP logic, as EPT doesn't interact with CR0.WP. - Move the TDX hardware setup code to tdx.c to better co-locate TDX code and eliminate a few global symbols. - 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). |
||
|
Paolo Bonzini
|
1a14928e2e |
Merge tag 'kvm-x86-misc-6.17' of https://github.com/kvm-x86/linux into HEAD
KVM x86 misc changes for 6.17 - Prevert the host's DEBUGCTL.FREEZE_IN_SMM (Intel only) when running the guest. Failure to honor FREEZE_IN_SMM can bleed host state into the guest. - Explicitly check vmcs12.GUEST_DEBUGCTL on nested VM-Enter (Intel only) to prevent L1 from running L2 with features that KVM doesn't support, e.g. BTF. - Intercept SPEC_CTRL on AMD if the MSR shouldn't exist according to the vCPU's CPUID model. - Rework the MSR interception code so that the SVM and VMX APIs are more or less identical. - Recalculate all MSR intercepts from the "source" on MSR filter changes, and drop the dedicated "shadow" bitmaps (and their awful "max" size defines). - WARN and reject loading kvm-amd.ko instead of panicking the kernel if the nested SVM MSRPM offsets tracker can't handle an MSR. - 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 stuffing INIT_RECEIVED, a.k.a. WFS, and then putting the vCPU into VMX Root Mode (post-VMXON). Use the same approach KVM uses for dealing with "impossible" emulation when running a !URG guest, and simply wait until KVM_RUN to detect that the vCPU has architecturally impossible state. - Add KVM_X86_DISABLE_EXITS_APERFMPERF to allow disabling interception of APERF/MPERF reads, so that a "properly" configured VM can "virtualize" APERF/MPERF (with many caveats). - Reject KVM_SET_TSC_KHZ if vCPUs have been created, as changing the "default" frequency is unsupported for VMs with a "secure" TSC, and there's no known use case for changing the default frequency for other VM types. |
||
|
Paolo Bonzini
|
f05efcfe07 |
Merge tag 'kvm-x86-mmio-6.17' of https://github.com/kvm-x86/linux into HEAD
KVM MMIO Stale Data mitigation cleanup for 6.17 Rework KVM's mitigation for the MMIO State Data vulnerability to track whether or not a vCPU has access to (host) MMIO based on the MMU that will be used when running in the guest. The current approach doesn't actually detect whether or not a guest has access to MMIO, and is prone to false negatives (and to a lesser extent, false positives), as KVM_DEV_VFIO_FILE_ADD is optional, and obviously only covers VFIO devices. |
||
|
Paolo Bonzini
|
f02b1bcc73 |
Merge tag 'kvm-x86-irqs-6.17' of https://github.com/kvm-x86/linux into HEAD
KVM IRQ changes for 6.17 - 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. - Add CONFIG_KVM_IOAPIC for x86 to allow disabling support for I/O APIC, PIC, and PIT emulation at compile time. - Drop x86's irq_comm.c, and move a pile of IRQ related code into irq.c. - Fix a variety of flaws and bugs in the AVIC device posted IRQ code. - Inhibited 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. - Dedup x86's device posted IRQ code, as the vast majority of functionality can be shared verbatime between SVM and VMX. - Harden the device posted IRQ code 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). - Generate 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. - 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. |
||
|
Jim Mattson
|
a7cec20845 |
KVM: x86: Provide a capability to disable APERF/MPERF read intercepts
Allow a guest to read the physical IA32_APERF and IA32_MPERF MSRs without interception. The IA32_APERF and IA32_MPERF MSRs are not virtualized. Writes are not handled at all. The MSR values are not zeroed on vCPU creation, saved on suspend, or restored on resume. No accommodation is made for processor migration or for sharing a logical processor with other tasks. No adjustments are made for non-unit TSC multipliers. The MSRs do not account for time the same way as the comparable PMU events, whether the PMU is virtualized by the traditional emulation method or the new mediated pass-through approach. Nonetheless, in a properly constrained environment, this capability can be combined with a guest CPUID table that advertises support for CPUID.6:ECX.APERFMPERF[bit 0] to induce a Linux guest to report the effective physical CPU frequency in /proc/cpuinfo. Moreover, there is no performance cost for this capability. Signed-off-by: Jim Mattson <jmattson@google.com> Link: https://lore.kernel.org/r/20250530185239.2335185-3-jmattson@google.com Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Link: https://lore.kernel.org/r/20250626001225.744268-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Jim Mattson
|
6fbef8615d |
KVM: x86: Replace growing set of *_in_guest bools with a u64
Store each "disabled exit" boolean in a single bit rather than a byte. No functional change intended. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Jim Mattson <jmattson@google.com> Link: https://lore.kernel.org/r/20250530185239.2335185-2-jmattson@google.com Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Link: https://lore.kernel.org/r/20250626001225.744268-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Sean Christopherson
|
83ebe71574 |
KVM: VMX: Apply MMIO Stale Data mitigation if KVM maps MMIO into the guest
Enforce the MMIO State Data mitigation if KVM has ever mapped host MMIO
into the VM, not if the VM has an assigned device. VFIO is but one of
many ways to map host MMIO into a KVM guest, and even within VFIO,
formally attaching a device to a VM via KVM_DEV_VFIO_FILE_ADD is entirely
optional.
Track whether or not the guest can access host MMIO on a per-MMU basis,
i.e. based on whether or not the vCPU has a mapping to host MMIO. For
simplicity, track MMIO mappings in "special" rools (those without a
kvm_mmu_page) at the VM level, as only Intel CPUs are vulnerable, and so
only legacy 32-bit shadow paging is affected, i.e. lack of precise
tracking is a complete non-issue.
Make the per-MMU and per-VM flags sticky. Detecting when *all* MMIO
mappings have been removed would be absurdly complex. And in practice,
removing MMIO from a guest will be done by deleting the associated memslot,
which by default will force KVM to re-allocate all roots. Special roots
will forever be mitigated, but as above, the affected scenarios are not
expected to be performance sensitive.
Use a VMX_RUN flag to communicate the need for a buffers flush to
vmx_vcpu_enter_exit() so that kvm_vcpu_can_access_host_mmio() and all its
dependencies don't need to be marked __always_inline, e.g. so that KASAN
doesn't trigger a noinstr violation.
Cc: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Fixes:
|
||
|
Chao Gao
|
3f06b8927a |
KVM: x86: Deduplicate MSR interception enabling and disabling
Extract a common function from MSR interception disabling logic and create disabling and enabling functions based on it. This removes most of the duplicated code for MSR interception disabling/enabling. No functional change intended. Signed-off-by: Chao Gao <chao.gao@intel.com> Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com> Link: https://lore.kernel.org/r/20250612081947.94081-2-chao.gao@intel.com [sean: s/enable/set, inline the wrappers] Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Sean Christopherson
|
ac777fbf06 |
KVM: x86: Use kvzalloc() to allocate VM struct
Allocate VM structs via kvzalloc(), i.e. try to use a contiguous physical
allocation before falling back to __vmalloc(), to avoid the overhead of
establishing the virtual mappings. For non-debug builds, The SVM and VMX
(and TDX) structures are now just below 7000 bytes in the worst case
scenario (see below), i.e. are order-1 allocations, and will likely remain
that way for quite some time.
Add compile-time assertions in vendor code to ensure the size of the
structures, sans the memslot hash tables, are order-0 allocations, i.e.
are less than 4KiB. There's nothing fundamentally wrong with a larger
kvm_{svm,vmx,tdx} size, but given that the size of the structure (without
the memslots hash tables) is below 2KiB after 18+ years of existence,
more than doubling the size would be quite notable.
Add sanity checks on the memslot hash table sizes, partly to ensure they
aren't resized without accounting for the impact on VM structure size, and
partly to document that the majority of the size of VM structures comes
from the memslots.
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Link: https://lore.kernel.org/r/20250523001138.3182794-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
||
|
Sean Christopherson
|
bafddc7000 |
KVM: VMX: Move enable_ipiv knob to common x86
Move enable_ipiv to common x86 so that it can be reused by SVM to control IPI virtualization when AVIC is enabled. SVM doesn't actually provide a way to truly disable IPI virtualization, but KVM can get close enough by skipping the necessary table programming. Link: https://lore.kernel.org/r/20250611224604.313496-18-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Sean Christopherson
|
bea44d1992 |
KVM: x86: Simplify userspace filter logic when disabling MSR interception
Refactor {svm,vmx}_disable_intercept_for_msr() to simplify the handling of
userspace filters that disallow access to an MSR. The more complicated
logic is no longer needed or justified now that KVM recalculates all MSR
intercepts on a userspace MSR filter change, i.e. now that KVM doesn't
need to also update shadow bitmaps.
No functional change intended.
Suggested-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://lore.kernel.org/r/20250610225737.156318-32-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
||
|
Sean Christopherson
|
4ceca57e3f |
KVM: x86: Rename msr_filter_changed() => recalc_msr_intercepts()
Rename msr_filter_changed() to recalc_msr_intercepts() and drop the trampoline wrapper now that both SVM and VMX use a filter-agnostic recalc helper to react to the new userspace filter. No functional change intended. Reviewed-by: Xin Li (Intel) <xin@zytor.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Link: https://lore.kernel.org/r/20250610225737.156318-21-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Sean Christopherson
|
8a056ece45 |
KVM: VMX: Manually recalc all MSR intercepts on userspace MSR filter change
On a userspace MSR filter change, recalculate all MSR intercepts using the filter-agnostic logic instead of maintaining a "shadow copy" of KVM's desired intercepts. The shadow bitmaps add yet another point of failure, are confusing (e.g. what does "handled specially" mean!?!?), an eyesore, and a maintenance burden. Given that KVM *must* be able to recalculate the correct intercepts at any given time, and that MSR filter updates are not hot paths, there is zero benefit to maintaining the shadow bitmaps. Opportunistically switch from boot_cpu_has() to cpu_feature_enabled() as appropriate. Link: https://lore.kernel.org/all/aCdPbZiYmtni4Bjs@google.com Link: https://lore.kernel.org/all/20241126180253.GAZ0YNTdXH1UGeqsu6@fat_crate.local Cc: Borislav Petkov <bp@alien8.de> Reviewed-by: Chao Gao <chao.gao@intel.com> Reviewed-by: Xin Li (Intel) <xin@zytor.com> Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Link: https://lore.kernel.org/r/20250610225737.156318-19-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Sean Christopherson
|
b1bccf7883 |
KVM: x86: Use non-atomic bit ops to manipulate "shadow" MSR intercepts
Manipulate the MSR bitmaps using non-atomic bit ops APIs (two underscores), as the bitmaps are per-vCPU and are only ever accessed while vcpu->mutex is held. Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Link: https://lore.kernel.org/r/20250610225737.156318-8-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Maxim Levitsky
|
6b1dd26544 |
KVM: VMX: Preserve host's DEBUGCTLMSR_FREEZE_IN_SMM while running the guest
Set/clear DEBUGCTLMSR_FREEZE_IN_SMM in GUEST_IA32_DEBUGCTL based on the host's pre-VM-Enter value, i.e. preserve the host's FREEZE_IN_SMM setting while running the guest. When running with the "default treatment of SMIs" in effect (the only mode KVM supports), SMIs do not generate a VM-Exit that is visible to host (non-SMM) software, and instead transitions directly from VMX non-root to SMM. And critically, DEBUGCTL isn't context switched by hardware on SMI or RSM, i.e. SMM will run with whatever value was resident in hardware at the time of the SMI. Failure to preserve FREEZE_IN_SMM results in the PMU unexpectedly counting events while the CPU is executing in SMM, which can pollute profiling and potentially leak information into the guest. Check for changes in FREEZE_IN_SMM prior to every entry into KVM's inner run loop, as the bit can be toggled in IRQ context via IPI callback (SMP function call), by way of /sys/devices/cpu/freeze_on_smi. Add a field in kvm_x86_ops to communicate which DEBUGCTL bits need to be preserved, as FREEZE_IN_SMM is only supported and defined for Intel CPUs, i.e. explicitly checking FREEZE_IN_SMM in common x86 is at best weird, and at worst could lead to undesirable behavior in the future if AMD CPUs ever happened to pick up a collision with the bit. Exempt TDX vCPUs, i.e. protected guests, from the check, as the TDX Module owns and controls GUEST_IA32_DEBUGCTL. WARN in SVM if KVM_RUN_LOAD_DEBUGCTL is set, mostly to document that the lack of handling isn't a KVM bug (TDX already WARNs on any run_flag). Lastly, explicitly reload GUEST_IA32_DEBUGCTL on a VM-Fail that is missed by KVM but detected by hardware, i.e. in nested_vmx_restore_host_state(). Doing so avoids the need to track host_debugctl on a per-VMCS basis, as GUEST_IA32_DEBUGCTL is unconditionally written by prepare_vmcs02() and load_vmcs12_host_state(). For the VM-Fail case, even though KVM won't have actually entered the guest, vcpu_enter_guest() will have run with vmcs02 active and thus could result in vmcs01 being run with a stale value. Cc: stable@vger.kernel.org Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> Co-developed-by: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/20250610232010.162191-9-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Maxim Levitsky
|
7d0cce6cbe |
KVM: VMX: Wrap all accesses to IA32_DEBUGCTL with getter/setter APIs
Introduce vmx_guest_debugctl_{read,write}() to handle all accesses to
vmcs.GUEST_IA32_DEBUGCTL. This will allow stuffing FREEZE_IN_SMM into
GUEST_IA32_DEBUGCTL based on the host setting without bleeding the state
into the guest, and without needing to copy+paste the FREEZE_IN_SMM
logic into every patch that accesses GUEST_IA32_DEBUGCTL.
No functional change intended.
Cc: stable@vger.kernel.org
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
[sean: massage changelog, make inline, use in all prepare_vmcs02() cases]
Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://lore.kernel.org/r/20250610232010.162191-8-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
||
|
Maxim Levitsky
|
095686e6fc |
KVM: nVMX: Check vmcs12->guest_ia32_debugctl on nested VM-Enter
Add a consistency check for L2's guest_ia32_debugctl, as KVM only supports a subset of hardware functionality, i.e. KVM can't rely on hardware to detect illegal/unsupported values. Failure to check the vmcs12 value would allow the guest to load any harware-supported value while running L2. Take care to exempt BTF and LBR from the validity check in order to match KVM's behavior for writes via WRMSR, but without clobbering vmcs12. Even if VM_EXIT_SAVE_DEBUG_CONTROLS is set in vmcs12, L1 can reasonably expect that vmcs12->guest_ia32_debugctl will not be modified if writes to the MSR are being intercepted. Arguably, KVM _should_ update vmcs12 if VM_EXIT_SAVE_DEBUG_CONTROLS is set *and* writes to MSR_IA32_DEBUGCTLMSR are not being intercepted by L1, but that would incur non-trivial complexity and wouldn't change the fact that KVM's handling of DEBUGCTL is blatantly broken. I.e. the extra complexity is not worth carrying. Cc: stable@vger.kernel.org Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> Co-developed-by: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/20250610232010.162191-7-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Sean Christopherson
|
8a4351ac30 |
KVM: VMX: Extract checking of guest's DEBUGCTL into helper
Move VMX's logic to check DEBUGCTL values into a standalone helper so that the code can be used by nested VM-Enter to apply the same logic to the value being loaded from vmcs12. KVM needs to explicitly check vmcs12->guest_ia32_debugctl on nested VM-Enter, as hardware may support features that KVM does not, i.e. relying on hardware to detect invalid guest state will result in false negatives. Unfortunately, that means applying KVM's funky suppression of BTF and LBR to vmcs12 so as not to break existing guests. No functional change intended. Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com> Link: https://lore.kernel.org/r/20250610232010.162191-6-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Sean Christopherson
|
17ec2f9653 |
KVM: VMX: Allow guest to set DEBUGCTL.RTM_DEBUG if RTM is supported
Let the guest set DEBUGCTL.RTM_DEBUG if RTM is supported according to the
guest CPUID model, as debug support is supposed to be available if RTM is
supported, and there are no known downsides to letting the guest debug RTM
aborts.
Note, there are no known bug reports related to RTM_DEBUG, the primary
motivation is to reduce the probability of breaking existing guests when a
future change adds a missing consistency check on vmcs12.GUEST_DEBUGCTL
(KVM currently lets L2 run with whatever hardware supports; whoops).
Note #2, KVM already emulates DR6.RTM, and doesn't restrict access to
DR7.RTM.
Fixes:
|
||
|
Sean Christopherson
|
80c64c7afe |
KVM: x86: Drop kvm_x86_ops.set_dr6() in favor of a new KVM_RUN flag
Instruct vendor code to load the guest's DR6 into hardware via a new KVM_RUN flag, and remove kvm_x86_ops.set_dr6(), whose sole purpose was to load vcpu->arch.dr6 into hardware when DR6 can be read/written directly by the guest. Note, TDX already WARNs on any run_flag being set, i.e. will yell if KVM thinks DR6 needs to be reloaded. TDX vCPUs force KVM_DEBUGREG_AUTO_SWITCH and never clear the flag, i.e. should never observe KVM_RUN_LOAD_GUEST_DR6. Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250610232010.162191-4-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Sean Christopherson
|
2478b1b220 |
KVM: x86: Convert vcpu_run()'s immediate exit param into a generic bitmap
Convert kvm_x86_ops.vcpu_run()'s "force_immediate_exit" boolean parameter into an a generic bitmap so that similar "take action" information can be passed to vendor code without creating a pile of boolean parameters. This will allow dropping kvm_x86_ops.set_dr6() in favor of a new flag, and will also allow for adding similar functionality for re-loading debugctl in the active VMCS. Opportunistically massage the TDX WARN and comment to prepare for adding more run_flags, all of which are expected to be mutually exclusive with TDX, i.e. should be WARNed on. No functional change intended. Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250610232010.162191-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Borislav Petkov (AMD)
|
f9af88a3d3 |
x86/bugs: Rename MDS machinery to something more generic
It will be used by other x86 mitigations. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> |
||
|
Linus Torvalds
|
7f9039c524 |
Generic:
* Clean up locking of all vCPUs for a VM by using the *_nest_lock()
family of functions, and move duplicated code to virt/kvm/.
kernel/ patches acked by Peter Zijlstra.
* Add MGLRU support to the access tracking perf test.
ARM fixes:
* Make the irqbypass hooks resilient to changes in the GSI<->MSI
routing, avoiding behind stale vLPI mappings being left behind. The
fix is to resolve the VGIC IRQ using the host IRQ (which is stable)
and nuking the vLPI mapping upon a routing change.
* Close another VGIC race where vCPU creation races with VGIC
creation, leading to in-flight vCPUs entering the kernel w/o private
IRQs allocated.
* Fix a build issue triggered by the recently added workaround for
Ampere's AC04_CPU_23 erratum.
* Correctly sign-extend the VA when emulating a TLBI instruction
potentially targeting a VNCR mapping.
* Avoid dereferencing a NULL pointer in the VGIC debug code, which can
happen if the device doesn't have any mapping yet.
s390:
* Fix interaction between some filesystems and Secure Execution
* Some cleanups and refactorings, preparing for an upcoming big series
x86:
* Wait for target vCPU to acknowledge KVM_REQ_UPDATE_PROTECTED_GUEST_STATE to
fix a race between AP destroy and VMRUN.
* Decrypt and dump the VMSA in dump_vmcb() if debugging enabled for the VM.
* Refine and harden handling of spurious faults.
* Add support for ALLOWED_SEV_FEATURES.
* Add #VMGEXIT to the set of handlers special cased for CONFIG_RETPOLINE=y.
* Treat DEBUGCTL[5:2] as reserved to pave the way for virtualizing features
that utilize those bits.
* Don't account temporary allocations in sev_send_update_data().
* Add support for KVM_CAP_X86_BUS_LOCK_EXIT on SVM, via Bus Lock Threshold.
* Unify virtualization of IBRS on nested VM-Exit, and cross-vCPU IBPB, between
SVM and VMX.
* Advertise support to userspace for WRMSRNS and PREFETCHI.
* Rescan I/O APIC routes after handling EOI that needed to be intercepted due
to the old/previous routing, but not the new/current routing.
* Add a module param to control and enumerate support for device posted
interrupts.
* Fix a potential overflow with nested virt on Intel systems running 32-bit kernels.
* Flush shadow VMCSes on emergency reboot.
* Add support for SNP to the various SEV selftests.
* Add a selftest to verify fastops instructions via forced emulation.
* Refine and optimize KVM's software processing of the posted interrupt bitmap, and share
the harvesting code between KVM and the kernel's Posted MSI handler
-----BEGIN PGP SIGNATURE-----
iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmg9TjwUHHBib256aW5p
QHJlZGhhdC5jb20ACgkQv/vSX3jHroOUxQf7B7nnWqIKd7jSkGzSD6YsSX9TXktr
2tJIOfWM3zNYg5GRCidg+m4Y5+DqQWd3Hi5hH2P9wUw7RNuOjOFsDe+y0VBr8ysE
ve39t/yp+mYalNmHVFl8s3dBDgrIeGKiz+Wgw3zCQIBZ18rJE1dREhv37RlYZ3a2
wSvuObe8sVpCTyKIowDs1xUi7qJUBoopMSuqfleSHawRrcgCpV99U8/KNFF5plLH
7fXOBAHHniVCVc+mqQN2wxtVJDhST+U3TaU4GwlKy9Yevr+iibdOXffveeIgNEU4
D6q1F2zKp6UdV3+p8hxyaTTbiCVDqsp9WOgY/0I/f+CddYn0WVZgOlR+ow==
=mYFL
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull more kvm updates from Paolo Bonzini:
Generic:
- Clean up locking of all vCPUs for a VM by using the *_nest_lock()
family of functions, and move duplicated code to virt/kvm/. kernel/
patches acked by Peter Zijlstra
- Add MGLRU support to the access tracking perf test
ARM fixes:
- Make the irqbypass hooks resilient to changes in the GSI<->MSI
routing, avoiding behind stale vLPI mappings being left behind. The
fix is to resolve the VGIC IRQ using the host IRQ (which is stable)
and nuking the vLPI mapping upon a routing change
- Close another VGIC race where vCPU creation races with VGIC
creation, leading to in-flight vCPUs entering the kernel w/o
private IRQs allocated
- Fix a build issue triggered by the recently added workaround for
Ampere's AC04_CPU_23 erratum
- Correctly sign-extend the VA when emulating a TLBI instruction
potentially targeting a VNCR mapping
- Avoid dereferencing a NULL pointer in the VGIC debug code, which
can happen if the device doesn't have any mapping yet
s390:
- Fix interaction between some filesystems and Secure Execution
- Some cleanups and refactorings, preparing for an upcoming big
series
x86:
- Wait for target vCPU to ack KVM_REQ_UPDATE_PROTECTED_GUEST_STATE
to fix a race between AP destroy and VMRUN
- Decrypt and dump the VMSA in dump_vmcb() if debugging enabled for
the VM
- Refine and harden handling of spurious faults
- Add support for ALLOWED_SEV_FEATURES
- Add #VMGEXIT to the set of handlers special cased for
CONFIG_RETPOLINE=y
- Treat DEBUGCTL[5:2] as reserved to pave the way for virtualizing
features that utilize those bits
- Don't account temporary allocations in sev_send_update_data()
- Add support for KVM_CAP_X86_BUS_LOCK_EXIT on SVM, via Bus Lock
Threshold
- Unify virtualization of IBRS on nested VM-Exit, and cross-vCPU
IBPB, between SVM and VMX
- Advertise support to userspace for WRMSRNS and PREFETCHI
- Rescan I/O APIC routes after handling EOI that needed to be
intercepted due to the old/previous routing, but not the
new/current routing
- Add a module param to control and enumerate support for device
posted interrupts
- Fix a potential overflow with nested virt on Intel systems running
32-bit kernels
- Flush shadow VMCSes on emergency reboot
- Add support for SNP to the various SEV selftests
- Add a selftest to verify fastops instructions via forced emulation
- Refine and optimize KVM's software processing of the posted
interrupt bitmap, and share the harvesting code between KVM and the
kernel's Posted MSI handler"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (93 commits)
rtmutex_api: provide correct extern functions
KVM: arm64: vgic-debug: Avoid dereferencing NULL ITE pointer
KVM: arm64: vgic-init: Plug vCPU vs. VGIC creation race
KVM: arm64: Unmap vLPIs affected by changes to GSI routing information
KVM: arm64: Resolve vLPI by host IRQ in vgic_v4_unset_forwarding()
KVM: arm64: Protect vLPI translation with vgic_irq::irq_lock
KVM: arm64: Use lock guard in vgic_v4_set_forwarding()
KVM: arm64: Mask out non-VA bits from TLBI VA* on VNCR invalidation
arm64: sysreg: Drag linux/kconfig.h to work around vdso build issue
KVM: s390: Simplify and move pv code
KVM: s390: Refactor and split some gmap helpers
KVM: s390: Remove unneeded srcu lock
s390: Remove unneeded includes
s390/uv: Improve splitting of large folios that cannot be split while dirty
s390/uv: Always return 0 from s390_wiggle_split_folio() if successful
s390/uv: Don't return 0 from make_hva_secure() if the operation was not successful
rust: add helper for mutex_trylock
RISC-V: KVM: use kvm_trylock_all_vcpus when locking all vCPUs
KVM: arm64: use kvm_trylock_all_vcpus when locking all vCPUs
x86: KVM: SVM: use kvm_lock_all_vcpus instead of a custom implementation
...
|
||
|
Linus Torvalds
|
43db111107 |
ARM:
* Add large stage-2 mapping (THP) support for non-protected guests when pKVM is enabled, clawing back some performance. * Enable nested virtualisation support on systems that support it, though it is disabled by default. * Add UBSAN support to the standalone EL2 object used in nVHE/hVHE and protected modes. * Large rework of the way KVM tracks architecture features and links them with the effects of control bits. While this has no functional impact, it ensures correctness of emulation (the data is automatically extracted from the published JSON files), and helps dealing with the evolution of the architecture. * Significant changes to the way pKVM tracks ownership of pages, avoiding page table walks by storing the state in the hypervisor's vmemmap. This in turn enables the THP support described above. * New selftest checking the pKVM ownership transition rules * Fixes for FEAT_MTE_ASYNC being accidentally advertised to guests even if the host didn't have it. * Fixes for the address translation emulation, which happened to be rather buggy in some specific contexts. * Fixes for the PMU emulation in NV contexts, decoupling PMCR_EL0.N from the number of counters exposed to a guest and addressing a number of issues in the process. * Add a new selftest for the SVE host state being corrupted by a guest. * Keep HCR_EL2.xMO set at all times for systems running with the kernel at EL2, ensuring that the window for interrupts is slightly bigger, and avoiding a pretty bad erratum on the AmpereOne HW. * Add workaround for AmpereOne's erratum AC04_CPU_23, which suffers from a pretty bad case of TLB corruption unless accesses to HCR_EL2 are heavily synchronised. * Add a per-VM, per-ITS debugfs entry to dump the state of the ITS tables in a human-friendly fashion. * and the usual random cleanups. LoongArch: * Don't flush tlb if the host supports hardware page table walks. * Add KVM selftests support. RISC-V: * Add vector registers to get-reg-list selftest * VCPU reset related improvements * Remove scounteren initialization from VCPU reset * Support VCPU reset from userspace using set_mpstate() ioctl x86: * Initial support for TDX in KVM. This finally makes it possible to use the TDX module to run confidential guests on Intel processors. This is quite a large series, including support for private page tables (managed by the TDX module and mirrored in KVM for efficiency), forwarding some TDVMCALLs to userspace, and handling several special VM exits from the TDX module. This has been in the works for literally years and it's not really possible to describe everything here, so I'll defer to the various merge commits up to and including commit |
||
|
Paolo Bonzini
|
3e89d5fdc7 |
KVM VMX changes for 6.16:
- Explicitly check MSR load/store list counts to fix a potential overflow on
32-bit kernels.
- Flush shadow VMCSes on emergency reboot.
- Revert mem_enc_ioctl() back to an optional hook, as it's nullified when
SEV or TDX is disabled via Kconfig.
- Macrofy the handling of vt_x86_ops to eliminate a pile of boilerplate code
needed for TDX, and to optimize CONFIG_KVM_INTEL_TDX=n builds.
-----BEGIN PGP SIGNATURE-----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=7W6U
-----END PGP SIGNATURE-----
Merge tag 'kvm-x86-vmx-6.16' of https://github.com/kvm-x86/linux into HEAD
KVM VMX changes for 6.16:
- Explicitly check MSR load/store list counts to fix a potential overflow on
32-bit kernels.
- Flush shadow VMCSes on emergency reboot.
- Revert mem_enc_ioctl() back to an optional hook, as it's nullified when
SEV or TDX is disabled via Kconfig.
- Macrofy the handling of vt_x86_ops to eliminate a pile of boilerplate code
needed for TDX, and to optimize CONFIG_KVM_INTEL_TDX=n builds.
|
||
|
Ingo Molnar
|
1f82e8e1ca |
Merge branch 'x86/msr' into x86/core, to resolve conflicts
Conflicts: arch/x86/boot/startup/sme.c arch/x86/coco/sev/core.c arch/x86/kernel/fpu/core.c arch/x86/kernel/fpu/xstate.c Semantic conflict: arch/x86/include/asm/sev-internal.h Signed-off-by: Ingo Molnar <mingo@kernel.org> |
||
|
Xin Li (Intel)
|
3204877d05 |
x86/msr: Convert __rdmsr() uses to native_rdmsrq() uses
__rdmsr() is the lowest level MSR write API, with native_rdmsr()
and native_rdmsrq() serving as higher-level wrappers around it.
#define native_rdmsr(msr, val1, val2) \
do { \
u64 __val = __rdmsr((msr)); \
(void)((val1) = (u32)__val); \
(void)((val2) = (u32)(__val >> 32)); \
} while (0)
static __always_inline u64 native_rdmsrq(u32 msr)
{
return __rdmsr(msr);
}
However, __rdmsr() continues to be utilized in various locations.
MSR APIs are designed for different scenarios, such as native or
pvops, with or without trace, and safe or non-safe. Unfortunately,
the current MSR API names do not adequately reflect these factors,
making it challenging to select the most appropriate API for
various situations.
To pave the way for improving MSR API names, convert __rdmsr()
uses to native_rdmsrq() to ensure consistent usage. Later, these
APIs can be renamed to better reflect their implications, such as
native or pvops, with or without trace, and safe or non-safe.
No functional change intended.
Signed-off-by: Xin Li (Intel) <xin@zytor.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Uros Bizjak <ubizjak@gmail.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20250427092027.1598740-10-xin@zytor.com
|
||
|
Xin Li (Intel)
|
efef7f184f |
x86/msr: Add explicit includes of <asm/msr.h>
For historic reasons there are some TSC-related functions in the
<asm/msr.h> header, even though there's an <asm/tsc.h> header.
To facilitate the relocation of rdtsc{,_ordered}() from <asm/msr.h>
to <asm/tsc.h> and to eventually eliminate the inclusion of
<asm/msr.h> in <asm/tsc.h>, add an explicit <asm/msr.h> dependency
to the source files that reference definitions from <asm/msr.h>.
[ mingo: Clarified the changelog. ]
Signed-off-by: Xin Li (Intel) <xin@zytor.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Uros Bizjak <ubizjak@gmail.com>
Link: https://lore.kernel.org/r/20250501054241.1245648-1-xin@zytor.com
|
||
|
David Kaplan
|
d43ba2dc8e |
x86/bugs: Restructure L1TF mitigation
Restructure L1TF to use select/apply functions to create consistent vulnerability handling. Define new AUTO mitigation for L1TF. Signed-off-by: David Kaplan <david.kaplan@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://lore.kernel.org/20250418161721.1855190-16-david.kaplan@amd.com |
||
|
Sean Christopherson
|
54a1a24fea |
KVM: x86: Unify cross-vCPU IBPB
Both SVM and VMX have similar implementation for executing an IBPB between running different vCPUs on the same CPU to create separate prediction domains for different vCPUs. For VMX, when the currently loaded VMCS is changed in vmx_vcpu_load_vmcs(), an IBPB is executed if there is no 'buddy', which is the case on vCPU load. The intention is to execute an IBPB when switching vCPUs, but not when switching the VMCS within the same vCPU. Executing an IBPB on nested transitions within the same vCPU is handled separately and conditionally in nested_vmx_vmexit(). For SVM, the current VMCB is tracked on vCPU load and an IBPB is executed when it is changed. The intention is also to execute an IBPB when switching vCPUs, although it is possible that in some cases an IBBP is executed when switching VMCBs for the same vCPU. Executing an IBPB on nested transitions should be handled separately, and is proposed at [1]. Unify the logic by tracking the last loaded vCPU and execuintg the IBPB on vCPU change in kvm_arch_vcpu_load() instead. When a vCPU is destroyed, make sure all references to it are removed from any CPU. This is similar to how SVM clears the current_vmcb tracking on vCPU destruction. Remove the current VMCB tracking in SVM as it is no longer required, as well as the 'buddy' parameter to vmx_vcpu_load_vmcs(). [1] https://lore.kernel.org/lkml/20250221163352.3818347-4-yosry.ahmed@linux.dev Link: https://lore.kernel.org/all/20250320013759.3965869-1-yosry.ahmed@linux.dev Signed-off-by: Yosry Ahmed <yosry.ahmed@linux.dev> [sean: tweak comment to stay at/under 80 columns] Signed-off-by: Sean Christopherson <seanjc@google.com> |
||
|
Chao Gao
|
a0ee1d5faf |
KVM: VMX: Flush shadow VMCS on emergency reboot
Ensure the shadow VMCS cache is evicted during an emergency reboot to
prevent potential memory corruption if the cache is evicted after reboot.
This issue was identified through code inspection, as __loaded_vmcs_clear()
flushes both the normal VMCS and the shadow VMCS.
Avoid checking the "launched" state during an emergency reboot, unlike the
behavior in __loaded_vmcs_clear(). This is important because reboot NMIs
can interfere with operations like copy_shadow_to_vmcs12(), where shadow
VMCSes are loaded directly using VMPTRLD. In such cases, if NMIs occur
right after the VMCS load, the shadow VMCSes will be active but the
"launched" state may not be set.
Fixes:
|
||
|
Sean Christopherson
|
459074cff6 |
KVM: x86: Add module param to control and enumerate device posted IRQs
Add a module param to each KVM vendor module to allow disabling device
posted interrupts without having to sacrifice all of APICv/AVIC, and to
also effectively enumerate to userspace whether or not KVM may be
utilizing device posted IRQs. Disabling device posted interrupts is
very desirable for testing, and can even be desirable for production
environments, e.g. if the host kernel wants to interpose on device
interrupts.
Put the module param in kvm-{amd,intel}.ko instead of kvm.ko to match
the overall APICv/AVIC controls, and to avoid complications with said
controls. E.g. if the param is in kvm.ko, KVM needs to be snapshot the
original user-defined value to play nice with a vendor module being
reloaded with different enable_apicv settings.
Link: https://lore.kernel.org/r/20250401161804.842968-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
||
|
Pawan Gupta
|
d9b79111fd |
x86/bugs: Rename mmio_stale_data_clear to cpu_buf_vm_clear
The static key mmio_stale_data_clear controls the KVM-only mitigation for MMIO Stale Data vulnerability. Rename it to reflect its purpose. No functional change. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/20250416-mmio-rename-v2-1-ad1f5488767c@linux.intel.com |
||
|
Ingo Molnar
|
7cbc2ba7c1 |
x86/msr: Rename 'native_wrmsrl()' to 'native_wrmsrq()'
Suggested-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Juergen Gross <jgross@suse.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Xin Li <xin@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Ingo Molnar
|
6fe22abacd |
x86/msr: Rename 'rdmsrl_safe()' to 'rdmsrq_safe()'
Suggested-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Juergen Gross <jgross@suse.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Xin Li <xin@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Ingo Molnar
|
78255eb239 |
x86/msr: Rename 'wrmsrl()' to 'wrmsrq()'
Suggested-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Juergen Gross <jgross@suse.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Xin Li <xin@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Ingo Molnar
|
c435e608cf |
x86/msr: Rename 'rdmsrl()' to 'rdmsrq()'
Suggested-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Juergen Gross <jgross@suse.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Xin Li <xin@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Paolo Bonzini
|
fd02aa45bd |
Merge branch 'kvm-tdx-initial' into HEAD
This large commit contains the initial support for TDX in KVM. All x86
parts enable the host-side hypercalls that KVM uses to talk to the TDX
module, a software component that runs in a special CPU mode called SEAM
(Secure Arbitration Mode).
The series is in turn split into multiple sub-series, each with a separate
merge commit:
- Initialization: basic setup for using the TDX module from KVM, plus
ioctls to create TDX VMs and vCPUs.
- MMU: in TDX, private and shared halves of the address space are mapped by
different EPT roots, and the private half is managed by the TDX module.
Using the support that was added to the generic MMU code in 6.14,
add support for TDX's secure page tables to the Intel side of KVM.
Generic KVM code takes care of maintaining a mirror of the secure page
tables so that they can be queried efficiently, and ensuring that changes
are applied to both the mirror and the secure EPT.
- vCPU enter/exit: implement the callbacks that handle the entry of a TDX
vCPU (via the SEAMCALL TDH.VP.ENTER) and the corresponding save/restore
of host state.
- Userspace exits: introduce support for guest TDVMCALLs that KVM forwards to
userspace. These correspond to the usual KVM_EXIT_* "heavyweight vmexits"
but are triggered through a different mechanism, similar to VMGEXIT for
SEV-ES and SEV-SNP.
- Interrupt handling: support for virtual interrupt injection as well as
handling VM-Exits that are caused by vectored events. Exclusive to
TDX are machine-check SMIs, which the kernel already knows how to
handle through the kernel machine check handler (commit
|
||
|
Linus Torvalds
|
edb0e8f6e2 |
ARM:
* Nested virtualization support for VGICv3, giving the nested
hypervisor control of the VGIC hardware when running an L2 VM
* Removal of 'late' nested virtualization feature register masking,
making the supported feature set directly visible to userspace
* Support for emulating FEAT_PMUv3 on Apple silicon, taking advantage
of an IMPLEMENTATION DEFINED trap that covers all PMUv3 registers
* Paravirtual interface for discovering the set of CPU implementations
where a VM may run, addressing a longstanding issue of guest CPU
errata awareness in big-little systems and cross-implementation VM
migration
* Userspace control of the registers responsible for identifying a
particular CPU implementation (MIDR_EL1, REVIDR_EL1, AIDR_EL1),
allowing VMs to be migrated cross-implementation
* pKVM updates, including support for tracking stage-2 page table
allocations in the protected hypervisor in the 'SecPageTable' stat
* Fixes to vPMU, ensuring that userspace updates to the vPMU after
KVM_RUN are reflected into the backing perf events
LoongArch:
* Remove unnecessary header include path
* Assume constant PGD during VM context switch
* Add perf events support for guest VM
RISC-V:
* Disable the kernel perf counter during configure
* KVM selftests improvements for PMU
* Fix warning at the time of KVM module removal
x86:
* Add support for aging of SPTEs without holding mmu_lock. Not taking mmu_lock
allows multiple aging actions to run in parallel, and more importantly avoids
stalling vCPUs. This includes an implementation of per-rmap-entry locking;
aging the gfn is done with only a per-rmap single-bin spinlock taken, whereas
locking an rmap for write requires taking both the per-rmap spinlock and
the mmu_lock.
Note that this decreases slightly the accuracy of accessed-page information,
because changes to the SPTE outside aging might not use atomic operations
even if they could race against a clear of the Accessed bit. This is
deliberate because KVM and mm/ tolerate false positives/negatives for
accessed information, and testing has shown that reducing the latency of
aging is far more beneficial to overall system performance than providing
"perfect" young/old information.
* Defer runtime CPUID updates until KVM emulates a CPUID instruction, to
coalesce updates when multiple pieces of vCPU state are changing, e.g. as
part of a nested transition.
* Fix a variety of nested emulation bugs, and add VMX support for synthesizing
nested VM-Exit on interception (instead of injecting #UD into L2).
* Drop "support" for async page faults for protected guests that do not set
SEND_ALWAYS (i.e. that only want async page faults at CPL3)
* Bring a bit of sanity to x86's VM teardown code, which has accumulated
a lot of cruft over the years. Particularly, destroy vCPUs before
the MMU, despite the latter being a VM-wide operation.
* Add common secure TSC infrastructure for use within SNP and in the
future TDX
* Block KVM_CAP_SYNC_REGS if guest state is protected. It does not make
sense to use the capability if the relevant registers are not
available for reading or writing.
* Don't take kvm->lock when iterating over vCPUs in the suspend notifier to
fix a largely theoretical deadlock.
* Use the vCPU's actual Xen PV clock information when starting the Xen timer,
as the cached state in arch.hv_clock can be stale/bogus.
* Fix a bug where KVM could bleed PVCLOCK_GUEST_STOPPED across different
PV clocks; restrict PVCLOCK_GUEST_STOPPED to kvmclock, as KVM's suspend
notifier only accounts for kvmclock, and there's no evidence that the
flag is actually supported by Xen guests.
* Clean up the per-vCPU "cache" of its reference pvclock, and instead only
track the vCPU's TSC scaling (multipler+shift) metadata (which is moderately
expensive to compute, and rarely changes for modern setups).
* Don't write to the Xen hypercall page on MSR writes that are initiated by
the host (userspace or KVM) to fix a class of bugs where KVM can write to
guest memory at unexpected times, e.g. during vCPU creation if userspace has
set the Xen hypercall MSR index to collide with an MSR that KVM emulates.
* Restrict the Xen hypercall MSR index to the unofficial synthetic range to
reduce the set of possible collisions with MSRs that are emulated by KVM
(collisions can still happen as KVM emulates Hyper-V MSRs, which also reside
in the synthetic range).
* Clean up and optimize KVM's handling of Xen MSR writes and xen_hvm_config.
* Update Xen TSC leaves during CPUID emulation instead of modifying the CPUID
entries when updating PV clocks; there is no guarantee PV clocks will be
updated between TSC frequency changes and CPUID emulation, and guest reads
of the TSC leaves should be rare, i.e. are not a hot path.
x86 (Intel):
* Fix a bug where KVM unnecessarily reads XFD_ERR from hardware and thus
modifies the vCPU's XFD_ERR on a #NM due to CR0.TS=1.
* Pass XFD_ERR as the payload when injecting #NM, as a preparatory step
for upcoming FRED virtualization support.
* Decouple the EPT entry RWX protection bit macros from the EPT Violation
bits, both as a general cleanup and in anticipation of adding support for
emulating Mode-Based Execution Control (MBEC).
* Reject KVM_RUN if userspace manages to gain control and stuff invalid guest
state while KVM is in the middle of emulating nested VM-Enter.
* Add a macro to handle KVM's sanity checks on entry/exit VMCS control pairs
in anticipation of adding sanity checks for secondary exit controls (the
primary field is out of bits).
x86 (AMD):
* Ensure the PSP driver is initialized when both the PSP and KVM modules are
built-in (the initcall framework doesn't handle dependencies).
* Use long-term pins when registering encrypted memory regions, so that the
pages are migrated out of MIGRATE_CMA/ZONE_MOVABLE and don't lead to
excessive fragmentation.
* Add macros and helpers for setting GHCB return/error codes.
* Add support for Idle HLT interception, which elides interception if the vCPU
has a pending, unmasked virtual IRQ when HLT is executed.
* Fix a bug in INVPCID emulation where KVM fails to check for a non-canonical
address.
* Don't attempt VMRUN for SEV-ES+ guests if the vCPU's VMSA is invalid, e.g.
because the vCPU was "destroyed" via SNP's AP Creation hypercall.
* Reject SNP AP Creation if the requested SEV features for the vCPU don't
match the VM's configured set of features.
Selftests:
* Fix again the Intel PMU counters test; add a data load and do CLFLUSH{OPT} on the data
instead of executing code. The theory is that modern Intel CPUs have
learned new code prefetching tricks that bypass the PMU counters.
* Fix a flaw in the Intel PMU counters test where it asserts that an event is
counting correctly without actually knowing what the event counts on the
underlying hardware.
* Fix a variety of flaws, bugs, and false failures/passes dirty_log_test, and
improve its coverage by collecting all dirty entries on each iteration.
* Fix a few minor bugs related to handling of stats FDs.
* Add infrastructure to make vCPU and VM stats FDs available to tests by
default (open the FDs during VM/vCPU creation).
* Relax an assertion on the number of HLT exits in the xAPIC IPI test when
running on a CPU that supports AMD's Idle HLT (which elides interception of
HLT if a virtual IRQ is pending and unmasked).
-----BEGIN PGP SIGNATURE-----
iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmfcTkEUHHBib256aW5p
QHJlZGhhdC5jb20ACgkQv/vSX3jHroMnQAf/cPx72hJOdNy4Qrm8M33YLXVRVV00
yEZ8eN8TWdOclr0ltE/w/ELGh/qS4CU8pjURAk0A6lPioU+mdcTn3dPEqMDMVYom
uOQ2lusEHw0UuSnGZSEjvZJsE/Ro2NSAsHIB6PWRqig1ZBPJzyu0frce34pMpeQH
diwriJL9lKPAhBWXnUQ9BKoi1R0P5OLW9ahX4SOWk7cAFg4DLlDE66Nqf6nKqViw
DwEucTiUEg5+a3d93gihdD4JNl+fb3vI2erxrMxjFjkacl0qgqRu3ei3DG0MfdHU
wNcFSG5B1n0OECKxr80lr1Ip1KTVNNij0Ks+w6Gc6lSg9c4PptnNkfLK3A==
=nnCN
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Paolo Bonzini:
"ARM:
- Nested virtualization support for VGICv3, giving the nested
hypervisor control of the VGIC hardware when running an L2 VM
- Removal of 'late' nested virtualization feature register masking,
making the supported feature set directly visible to userspace
- Support for emulating FEAT_PMUv3 on Apple silicon, taking advantage
of an IMPLEMENTATION DEFINED trap that covers all PMUv3 registers
- Paravirtual interface for discovering the set of CPU
implementations where a VM may run, addressing a longstanding issue
of guest CPU errata awareness in big-little systems and
cross-implementation VM migration
- Userspace control of the registers responsible for identifying a
particular CPU implementation (MIDR_EL1, REVIDR_EL1, AIDR_EL1),
allowing VMs to be migrated cross-implementation
- pKVM updates, including support for tracking stage-2 page table
allocations in the protected hypervisor in the 'SecPageTable' stat
- Fixes to vPMU, ensuring that userspace updates to the vPMU after
KVM_RUN are reflected into the backing perf events
LoongArch:
- Remove unnecessary header include path
- Assume constant PGD during VM context switch
- Add perf events support for guest VM
RISC-V:
- Disable the kernel perf counter during configure
- KVM selftests improvements for PMU
- Fix warning at the time of KVM module removal
x86:
- Add support for aging of SPTEs without holding mmu_lock.
Not taking mmu_lock allows multiple aging actions to run in
parallel, and more importantly avoids stalling vCPUs. This includes
an implementation of per-rmap-entry locking; aging the gfn is done
with only a per-rmap single-bin spinlock taken, whereas locking an
rmap for write requires taking both the per-rmap spinlock and the
mmu_lock.
Note that this decreases slightly the accuracy of accessed-page
information, because changes to the SPTE outside aging might not
use atomic operations even if they could race against a clear of
the Accessed bit.
This is deliberate because KVM and mm/ tolerate false
positives/negatives for accessed information, and testing has shown
that reducing the latency of aging is far more beneficial to
overall system performance than providing "perfect" young/old
information.
- Defer runtime CPUID updates until KVM emulates a CPUID instruction,
to coalesce updates when multiple pieces of vCPU state are
changing, e.g. as part of a nested transition
- Fix a variety of nested emulation bugs, and add VMX support for
synthesizing nested VM-Exit on interception (instead of injecting
#UD into L2)
- Drop "support" for async page faults for protected guests that do
not set SEND_ALWAYS (i.e. that only want async page faults at CPL3)
- Bring a bit of sanity to x86's VM teardown code, which has
accumulated a lot of cruft over the years. Particularly, destroy
vCPUs before the MMU, despite the latter being a VM-wide operation
- Add common secure TSC infrastructure for use within SNP and in the
future TDX
- Block KVM_CAP_SYNC_REGS if guest state is protected. It does not
make sense to use the capability if the relevant registers are not
available for reading or writing
- Don't take kvm->lock when iterating over vCPUs in the suspend
notifier to fix a largely theoretical deadlock
- Use the vCPU's actual Xen PV clock information when starting the
Xen timer, as the cached state in arch.hv_clock can be stale/bogus
- Fix a bug where KVM could bleed PVCLOCK_GUEST_STOPPED across
different PV clocks; restrict PVCLOCK_GUEST_STOPPED to kvmclock, as
KVM's suspend notifier only accounts for kvmclock, and there's no
evidence that the flag is actually supported by Xen guests
- Clean up the per-vCPU "cache" of its reference pvclock, and instead
only track the vCPU's TSC scaling (multipler+shift) metadata (which
is moderately expensive to compute, and rarely changes for modern
setups)
- Don't write to the Xen hypercall page on MSR writes that are
initiated by the host (userspace or KVM) to fix a class of bugs
where KVM can write to guest memory at unexpected times, e.g.
during vCPU creation if userspace has set the Xen hypercall MSR
index to collide with an MSR that KVM emulates
- Restrict the Xen hypercall MSR index to the unofficial synthetic
range to reduce the set of possible collisions with MSRs that are
emulated by KVM (collisions can still happen as KVM emulates
Hyper-V MSRs, which also reside in the synthetic range)
- Clean up and optimize KVM's handling of Xen MSR writes and
xen_hvm_config
- Update Xen TSC leaves during CPUID emulation instead of modifying
the CPUID entries when updating PV clocks; there is no guarantee PV
clocks will be updated between TSC frequency changes and CPUID
emulation, and guest reads of the TSC leaves should be rare, i.e.
are not a hot path
x86 (Intel):
- Fix a bug where KVM unnecessarily reads XFD_ERR from hardware and
thus modifies the vCPU's XFD_ERR on a #NM due to CR0.TS=1
- Pass XFD_ERR as the payload when injecting #NM, as a preparatory
step for upcoming FRED virtualization support
- Decouple the EPT entry RWX protection bit macros from the EPT
Violation bits, both as a general cleanup and in anticipation of
adding support for emulating Mode-Based Execution Control (MBEC)
- Reject KVM_RUN if userspace manages to gain control and stuff
invalid guest state while KVM is in the middle of emulating nested
VM-Enter
- Add a macro to handle KVM's sanity checks on entry/exit VMCS
control pairs in anticipation of adding sanity checks for secondary
exit controls (the primary field is out of bits)
x86 (AMD):
- Ensure the PSP driver is initialized when both the PSP and KVM
modules are built-in (the initcall framework doesn't handle
dependencies)
- Use long-term pins when registering encrypted memory regions, so
that the pages are migrated out of MIGRATE_CMA/ZONE_MOVABLE and
don't lead to excessive fragmentation
- Add macros and helpers for setting GHCB return/error codes
- Add support for Idle HLT interception, which elides interception if
the vCPU has a pending, unmasked virtual IRQ when HLT is executed
- Fix a bug in INVPCID emulation where KVM fails to check for a
non-canonical address
- Don't attempt VMRUN for SEV-ES+ guests if the vCPU's VMSA is
invalid, e.g. because the vCPU was "destroyed" via SNP's AP
Creation hypercall
- Reject SNP AP Creation if the requested SEV features for the vCPU
don't match the VM's configured set of features
Selftests:
- Fix again the Intel PMU counters test; add a data load and do
CLFLUSH{OPT} on the data instead of executing code. The theory is
that modern Intel CPUs have learned new code prefetching tricks
that bypass the PMU counters
- Fix a flaw in the Intel PMU counters test where it asserts that an
event is counting correctly without actually knowing what the event
counts on the underlying hardware
- Fix a variety of flaws, bugs, and false failures/passes
dirty_log_test, and improve its coverage by collecting all dirty
entries on each iteration
- Fix a few minor bugs related to handling of stats FDs
- Add infrastructure to make vCPU and VM stats FDs available to tests
by default (open the FDs during VM/vCPU creation)
- Relax an assertion on the number of HLT exits in the xAPIC IPI test
when running on a CPU that supports AMD's Idle HLT (which elides
interception of HLT if a virtual IRQ is pending and unmasked)"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (216 commits)
RISC-V: KVM: Optimize comments in kvm_riscv_vcpu_isa_disable_allowed
RISC-V: KVM: Teardown riscv specific bits after kvm_exit
LoongArch: KVM: Register perf callbacks for guest
LoongArch: KVM: Implement arch-specific functions for guest perf
LoongArch: KVM: Add stub for kvm_arch_vcpu_preempted_in_kernel()
LoongArch: KVM: Remove PGD saving during VM context switch
LoongArch: KVM: Remove unnecessary header include path
KVM: arm64: Tear down vGIC on failed vCPU creation
KVM: arm64: PMU: Reload when resetting
KVM: arm64: PMU: Reload when user modifies registers
KVM: arm64: PMU: Fix SET_ONE_REG for vPMC regs
KVM: arm64: PMU: Assume PMU presence in pmu-emul.c
KVM: arm64: PMU: Set raw values from user to PM{C,I}NTEN{SET,CLR}, PMOVS{SET,CLR}
KVM: arm64: Create each pKVM hyp vcpu after its corresponding host vcpu
KVM: arm64: Factor out pKVM hyp vcpu creation to separate function
KVM: arm64: Initialize HCRX_EL2 traps in pKVM
KVM: arm64: Factor out setting HCRX_EL2 traps into separate function
KVM: x86: block KVM_CAP_SYNC_REGS if guest state is protected
KVM: x86: Add infrastructure for secure TSC
KVM: x86: Push down setting vcpu.arch.user_set_tsc
...
|
||
|
Linus Torvalds
|
906174776c |
- Some preparatory work to convert the mitigations machinery to mitigating
attack vectors instead of single vulnerabilities - Untangle and remove a now unneeded X86_FEATURE_USE_IBPB flag - Add support for a Zen5-specific SRSO mitigation - Cleanups and minor improvements -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmfixS0ACgkQEsHwGGHe VUpi1xAAgvH2u8Eo8ibT5dABQpD65w3oQiykO+9aDpObG9w9beDVGlld8DJE61Rz 6tcE0Clp2H/tMcCbn8zXIJ92TQ3wIX/85uZwLi1VEM1Tx7A6VtAbPv8WKfZE3FCX 9v92HRKnK3ql+A2ZR+oyy+/8RedUmia7y7/bXH1H7Zf2uozoKkmq5cQnwfq5iU4A qNiKuvSlQwjZ8Zz6Ax1ugHUkE4R7mlKh8rccLXl4+mVr63/lkPHSY3OFTjcYf4HW Ir92N86Spfo0/l0vsOOsWoYKmoaiVP7ouJh7YbKR3B0BGN0pt2MT476mehkEs427 m4J6XhRKhIrsYmzEkLvvpsg12zO4/PKk8BEYNS7YPYlRaOwjV4ivyFS2aY6e55rh yUHyo9s+16f/Mp+/fNFXll3mdMxYBioPWh3M191nJkdfyKMrtf0MdKPRibaJB8wH yMF4D1gMx+hFbs0/VOS6dtqD9DKW7VgPg0LW+RysfhnLTuFFb5iBcH6Of7l7Z/Ca vVK+JxrhB1EDVI1+MKnESKPF9c6j3DRa2xrQHi/XYje1TGqnQ1v4CmsEObYBuJDN 9M9t4QLzNuA/DA5tS7cxxtQ3YUthuJjPLcO4EVHOCvnqCAxkzp0i3dVMUr+YISl+ 2yFqaZdTt8s8FjTI21LOyuloCo30ZLlzaorFa0lp2cIyYup+1vg= =btX/ -----END PGP SIGNATURE----- Merge tag 'x86_bugs_for_v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 speculation mitigation updates from Borislav Petkov: - Some preparatory work to convert the mitigations machinery to mitigating attack vectors instead of single vulnerabilities - Untangle and remove a now unneeded X86_FEATURE_USE_IBPB flag - Add support for a Zen5-specific SRSO mitigation - Cleanups and minor improvements * tag 'x86_bugs_for_v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/bugs: Make spectre user default depend on MITIGATION_SPECTRE_V2 x86/bugs: Use the cpu_smt_possible() helper instead of open-coded code x86/bugs: Add AUTO mitigations for mds/taa/mmio/rfds x86/bugs: Relocate mds/taa/mmio/rfds defines x86/bugs: Add X86_BUG_SPECTRE_V2_USER x86/bugs: Remove X86_FEATURE_USE_IBPB KVM: nVMX: Always use IBPB to properly virtualize IBRS x86/bugs: Use a static branch to guard IBPB on vCPU switch x86/bugs: Remove the X86_FEATURE_USE_IBPB check in ib_prctl_set() x86/mm: Remove X86_FEATURE_USE_IBPB checks in cond_mitigation() x86/bugs: Move the X86_FEATURE_USE_IBPB check into callers x86/bugs: KVM: Add support for SRSO_MSR_FIX |
||
|
Paolo Bonzini
|
a24dbf986b |
KVM VMX changes for 6.15
- Fix a bug where KVM unnecessarily reads XFD_ERR from hardware and thus
modifies the vCPU's XFD_ERR on a #NM due to CR0.TS=1.
- Pass XFD_ERR as a psueo-payload when injecting #NM as a preparatory step
for upcoming FRED virtualization support.
- Decouple the EPT entry RWX protection bit macros from the EPT Violation bits
as a general cleanup, and in anticipation of adding support for emulating
Mode-Based Execution (MBEC).
- Reject KVM_RUN if userspace manages to gain control and stuff invalid guest
state while KVM is in the middle of emulating nested VM-Enter.
- Add a macro to handle KVM's sanity checks on entry/exit VMCS control pairs
in anticipation of adding sanity checks for secondary exit controls (the
primary field is out of bits).
-----BEGIN PGP SIGNATURE-----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=SAgZ
-----END PGP SIGNATURE-----
Merge tag 'kvm-x86-vmx-6.15' of https://github.com/kvm-x86/linux into HEAD
KVM VMX changes for 6.15
- Fix a bug where KVM unnecessarily reads XFD_ERR from hardware and thus
modifies the vCPU's XFD_ERR on a #NM due to CR0.TS=1.
- Pass XFD_ERR as a psueo-payload when injecting #NM as a preparatory step
for upcoming FRED virtualization support.
- Decouple the EPT entry RWX protection bit macros from the EPT Violation bits
as a general cleanup, and in anticipation of adding support for emulating
Mode-Based Execution (MBEC).
- Reject KVM_RUN if userspace manages to gain control and stuff invalid guest
state while KVM is in the middle of emulating nested VM-Enter.
- Add a macro to handle KVM's sanity checks on entry/exit VMCS control pairs
in anticipation of adding sanity checks for secondary exit controls (the
primary field is out of bits).
|
||
|
Paolo Bonzini
|
4d9a677596 |
KVM x86 misc changes for 6.15:
- Fix a bug in PIC emulation that caused KVM to emit a spurious KVM_REQ_EVENT.
- Add a helper to consolidate handling of mp_state transitions, and use it to
clear pv_unhalted whenever a vCPU is made RUNNABLE.
- Defer runtime CPUID updates until KVM emulates a CPUID instruction, to
coalesce updates when multiple pieces of vCPU state are changing, e.g. as
part of a nested transition.
- Fix a variety of nested emulation bugs, and add VMX support for synthesizing
nested VM-Exit on interception (instead of injecting #UD into L2).
- Drop "support" for PV Async #PF with proctected guests without SEND_ALWAYS,
as KVM can't get the current CPL.
- Misc cleanups
-----BEGIN PGP SIGNATURE-----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=8SGF
-----END PGP SIGNATURE-----
Merge tag 'kvm-x86-misc-6.15' of https://github.com/kvm-x86/linux into HEAD
KVM x86 misc changes for 6.15:
- Fix a bug in PIC emulation that caused KVM to emit a spurious KVM_REQ_EVENT.
- Add a helper to consolidate handling of mp_state transitions, and use it to
clear pv_unhalted whenever a vCPU is made RUNNABLE.
- Defer runtime CPUID updates until KVM emulates a CPUID instruction, to
coalesce updates when multiple pieces of vCPU state are changing, e.g. as
part of a nested transition.
- Fix a variety of nested emulation bugs, and add VMX support for synthesizing
nested VM-Exit on interception (instead of injecting #UD into L2).
- Drop "support" for PV Async #PF with proctected guests without SEND_ALWAYS,
as KVM can't get the current CPL.
- Misc cleanups
|
||
|
Paolo Bonzini
|
3fee4837ef |
KVM: x86: remove shadow_memtype_mask
The IGNORE_GUEST_PAT quirk is inapplicable, and thus always-disabled, if shadow_memtype_mask is zero. As long as vmx_get_mt_mask is not called for the shadow paging case, there is no need to consult shadow_memtype_mask and it can be removed altogether. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Yan Zhao
|
c9c1e20b4c |
KVM: x86: Introduce Intel specific quirk KVM_X86_QUIRK_IGNORE_GUEST_PAT
Introduce an Intel specific quirk KVM_X86_QUIRK_IGNORE_GUEST_PAT to have KVM ignore guest PAT when this quirk is enabled. On AMD platforms, KVM always honors guest PAT. On Intel however there are two issues. First, KVM *cannot* honor guest PAT if CPU feature self-snoop is not supported. Second, UC access on certain Intel platforms can be very slow[1] and honoring guest PAT on those platforms may break some old guests that accidentally specify video RAM as UC. Those old guests may never expect the slowness since KVM always forces WB previously. See [2]. So, introduce a quirk that KVM can enable by default on all Intel platforms to avoid breaking old unmodifiable guests. Newer userspace can disable this quirk if it wishes KVM to honor guest PAT; disabling the quirk will fail if self-snoop is not supported, i.e. if KVM cannot obey the wish. The quirk is a no-op on AMD and also if any assigned devices have non-coherent DMA. This is not an issue, as KVM_X86_QUIRK_CD_NW_CLEARED is another example of a quirk that is sometimes automatically disabled. Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Suggested-by: Sean Christopherson <seanjc@google.com> Cc: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Yan Zhao <yan.y.zhao@intel.com> Link: https://lore.kernel.org/all/Ztl9NWCOupNfVaCA@yzhao56-desk.sh.intel.com # [1] Link: https://lore.kernel.org/all/87jzfutmfc.fsf@redhat.com # [2] Message-ID: <20250224070946.31482-1-yan.y.zhao@intel.com> [Use supported_quirks/inapplicable_quirks to support both AMD and no-self-snoop cases, as well as to remove the shadow_memtype_mask check from kvm_mmu_may_ignore_guest_pat(). - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Isaku Yamahata
|
f30cb6429f |
KVM: TDX: Handle EXCEPTION_NMI and EXTERNAL_INTERRUPT
Handle EXCEPTION_NMI and EXTERNAL_INTERRUPT exits for TDX. NMI Handling: Just like the VMX case, NMI remains blocked after exiting from TDX guest for NMI-induced exits [*]. Handle NMI-induced exits for TDX guests in the same way as they are handled for VMX guests, i.e., handle NMI in tdx_vcpu_enter_exit() by calling the vmx_handle_nmi() helper. Interrupt and Exception Handling: Similar to the VMX case, external interrupts and exceptions (machine check is the only exception type KVM handles for TDX guests) are handled in the .handle_exit_irqoff() callback. For other exceptions, because TDX guest state is protected, exceptions in TDX guests can't be intercepted. TDX VMM isn't supposed to handle these exceptions. If unexpected exception occurs, exit to userspace with KVM_EXIT_EXCEPTION. For external interrupt, increase the statistics, same as the VMX case. [*]: Some old TDX modules have a bug which makes NMI unblocked after exiting from TDX guest for NMI-induced exits. This could potentially lead to nested NMIs: a new NMI arrives when KVM is manually calling the host NMI handler. This is an architectural violation, but it doesn't have real harm until FRED is enabled together with TDX (for non-FRED, the host NMI handler can handle nested NMIs). Given this is rare to happen and has no real harm, ignore this for the initial TDX support. Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Co-developed-by: Binbin Wu <binbin.wu@linux.intel.com> Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-ID: <20250222014757.897978-16-binbin.wu@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Sean Christopherson
|
7e548b0d90 |
KVM: VMX: Add a helper for NMI handling
Add a helper to handles NMI exit. TDX handles the NMI exit the same as VMX case. Add a helper to share the code with TDX, expose the helper in common.h. No functional change intended. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Co-developed-by: Binbin Wu <binbin.wu@linux.intel.com> Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com> Message-ID: <20250222014757.897978-15-binbin.wu@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Binbin Wu
|
d5bc91e8e7 |
KVM: VMX: Move emulation_required to struct vcpu_vt
Move emulation_required from struct vcpu_vmx to struct vcpu_vt so that vmx_handle_exit_irqoff() can be reused by TDX code. No functional change intended. Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com> Message-ID: <20250222014757.897978-14-binbin.wu@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Isaku Yamahata
|
24c1291116 |
KVM: TDX: Implement non-NMI interrupt injection
Implement non-NMI interrupt injection for TDX via posted interrupt. As CPU state is protected and APICv is enabled for the TDX guest, TDX supports non-NMI interrupt injection only by posted interrupt. Posted interrupt descriptors (PIDs) are allocated in shared memory, KVM can update them directly. If target vCPU is in non-root mode, send posted interrupt notification to the vCPU and hardware will sync PIR to vIRR atomically. Otherwise, kick it to pick up the interrupt from PID. To post pending interrupts in the PID, KVM can generate a self-IPI with notification vector prior to TD entry. Since the guest status of TD vCPU is protected, assume interrupt is always allowed. Ignore the code path for event injection mechanism or LAPIC emulation for TDX. Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Co-developed-by: Binbin Wu <binbin.wu@linux.intel.com> Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-ID: <20250222014757.897978-5-binbin.wu@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Isaku Yamahata
|
254e5dcd5a |
KVM: VMX: Move posted interrupt delivery code to common header
Move posted interrupt delivery code to common header so that TDX can leverage it. No functional change intended. Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> [binbin: split into new patch] Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Chao Gao <chao.gao@intel.com> Message-ID: <20250222014757.897978-4-binbin.wu@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
||
|
Binbin Wu
|
7172c753c2 |
KVM: VMX: Move common fields of struct vcpu_{vmx,tdx} to a struct
Move common fields of struct vcpu_vmx and struct vcpu_tdx to struct vcpu_vt, to share the code between VMX/TDX as much as possible and to make TDX exit handling more VMX like. No functional change intended. [Adrian: move code that depends on struct vcpu_vmx back to vmx.h] Suggested-by: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/Z1suNzg2Or743a7e@google.com Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Message-ID: <20250129095902.16391-5-adrian.hunter@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |