Commit Graph

300 Commits

Author SHA1 Message Date
Linus Torvalds
7c5c3a6177 ARM:
* Unwinder implementations for both nVHE modes (classic and
   protected), complete with an overflow stack
 
 * Rework of the sysreg access from userspace, with a complete
   rewrite of the vgic-v3 view to allign with the rest of the
   infrastructure
 
 * Disagregation of the vcpu flags in separate sets to better track
   their use model.
 
 * A fix for the GICv2-on-v3 selftest
 
 * A small set of cosmetic fixes
 
 RISC-V:
 
 * Track ISA extensions used by Guest using bitmap
 
 * Added system instruction emulation framework
 
 * Added CSR emulation framework
 
 * Added gfp_custom flag in struct kvm_mmu_memory_cache
 
 * Added G-stage ioremap() and iounmap() functions
 
 * Added support for Svpbmt inside Guest
 
 s390:
 
 * add an interface to provide a hypervisor dump for secure guests
 
 * improve selftests to use TAP interface
 
 * enable interpretive execution of zPCI instructions (for PCI passthrough)
 
 * First part of deferred teardown
 
 * CPU Topology
 
 * PV attestation
 
 * Minor fixes
 
 x86:
 
 * Permit guests to ignore single-bit ECC errors
 
 * Intel IPI virtualization
 
 * Allow getting/setting pending triple fault with KVM_GET/SET_VCPU_EVENTS
 
 * PEBS virtualization
 
 * Simplify PMU emulation by just using PERF_TYPE_RAW events
 
 * More accurate event reinjection on SVM (avoid retrying instructions)
 
 * Allow getting/setting the state of the speaker port data bit
 
 * Refuse starting the kvm-intel module if VM-Entry/VM-Exit controls are inconsistent
 
 * "Notify" VM exit (detect microarchitectural hangs) for Intel
 
 * Use try_cmpxchg64 instead of cmpxchg64
 
 * Ignore benign host accesses to PMU MSRs when PMU is disabled
 
 * Allow disabling KVM's "MONITOR/MWAIT are NOPs!" behavior
 
 * Allow NX huge page mitigation to be disabled on a per-vm basis
 
 * Port eager page splitting to shadow MMU as well
 
 * Enable CMCI capability by default and handle injected UCNA errors
 
 * Expose pid of vcpu threads in debugfs
 
 * x2AVIC support for AMD
 
 * cleanup PIO emulation
 
 * Fixes for LLDT/LTR emulation
 
 * Don't require refcounted "struct page" to create huge SPTEs
 
 * Miscellaneous cleanups:
 ** MCE MSR emulation
 ** Use separate namespaces for guest PTEs and shadow PTEs bitmasks
 ** PIO emulation
 ** Reorganize rmap API, mostly around rmap destruction
 ** Do not workaround very old KVM bugs for L0 that runs with nesting enabled
 ** new selftests API for CPUID
 
 Generic:
 
 * Fix races in gfn->pfn cache refresh; do not pin pages tracked by the cache
 
 * new selftests API using struct kvm_vcpu instead of a (vm, id) tuple
 -----BEGIN PGP SIGNATURE-----
 
 iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmLnyo4UHHBib256aW5p
 QHJlZGhhdC5jb20ACgkQv/vSX3jHroMtQQf/XjVWiRcWLPR9dqzRM/vvRXpiG+UL
 jU93R7m6ma99aqTtrxV/AE+kHgamBlma3Cwo+AcWk9uCVNbIhFjv2YKg6HptKU0e
 oJT3zRYp+XIjEo7Kfw+TwroZbTlG6gN83l1oBLFMqiFmHsMLnXSI2mm8MXyi3dNB
 vR2uIcTAl58KIprqNNsYJ2dNn74ogOMiXYx9XzoA9/5Xb6c0h4rreHJa5t+0s9RO
 Gz7Io3PxumgsbJngjyL1Ve5oxhlIAcZA8DU0PQmjxo3eS+k6BcmavGFd45gNL5zg
 iLpCh4k86spmzh8CWkAAwWPQE4dZknK6jTctJc0OFVad3Z7+X7n0E8TFrA==
 =PM8o
 -----END PGP SIGNATURE-----

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

Pull kvm updates from Paolo Bonzini:
 "Quite a large pull request due to a selftest API overhaul and some
  patches that had come in too late for 5.19.

  ARM:

   - Unwinder implementations for both nVHE modes (classic and
     protected), complete with an overflow stack

   - Rework of the sysreg access from userspace, with a complete rewrite
     of the vgic-v3 view to allign with the rest of the infrastructure

   - Disagregation of the vcpu flags in separate sets to better track
     their use model.

   - A fix for the GICv2-on-v3 selftest

   - A small set of cosmetic fixes

  RISC-V:

   - Track ISA extensions used by Guest using bitmap

   - Added system instruction emulation framework

   - Added CSR emulation framework

   - Added gfp_custom flag in struct kvm_mmu_memory_cache

   - Added G-stage ioremap() and iounmap() functions

   - Added support for Svpbmt inside Guest

  s390:

   - add an interface to provide a hypervisor dump for secure guests

   - improve selftests to use TAP interface

   - enable interpretive execution of zPCI instructions (for PCI
     passthrough)

   - First part of deferred teardown

   - CPU Topology

   - PV attestation

   - Minor fixes

  x86:

   - Permit guests to ignore single-bit ECC errors

   - Intel IPI virtualization

   - Allow getting/setting pending triple fault with
     KVM_GET/SET_VCPU_EVENTS

   - PEBS virtualization

   - Simplify PMU emulation by just using PERF_TYPE_RAW events

   - More accurate event reinjection on SVM (avoid retrying
     instructions)

   - Allow getting/setting the state of the speaker port data bit

   - Refuse starting the kvm-intel module if VM-Entry/VM-Exit controls
     are inconsistent

   - "Notify" VM exit (detect microarchitectural hangs) for Intel

   - Use try_cmpxchg64 instead of cmpxchg64

   - Ignore benign host accesses to PMU MSRs when PMU is disabled

   - Allow disabling KVM's "MONITOR/MWAIT are NOPs!" behavior

   - Allow NX huge page mitigation to be disabled on a per-vm basis

   - Port eager page splitting to shadow MMU as well

   - Enable CMCI capability by default and handle injected UCNA errors

   - Expose pid of vcpu threads in debugfs

   - x2AVIC support for AMD

   - cleanup PIO emulation

   - Fixes for LLDT/LTR emulation

   - Don't require refcounted "struct page" to create huge SPTEs

   - Miscellaneous cleanups:
      - MCE MSR emulation
      - Use separate namespaces for guest PTEs and shadow PTEs bitmasks
      - PIO emulation
      - Reorganize rmap API, mostly around rmap destruction
      - Do not workaround very old KVM bugs for L0 that runs with nesting enabled
      - new selftests API for CPUID

  Generic:

   - Fix races in gfn->pfn cache refresh; do not pin pages tracked by
     the cache

   - new selftests API using struct kvm_vcpu instead of a (vm, id)
     tuple"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (606 commits)
  selftests: kvm: set rax before vmcall
  selftests: KVM: Add exponent check for boolean stats
  selftests: KVM: Provide descriptive assertions in kvm_binary_stats_test
  selftests: KVM: Check stat name before other fields
  KVM: x86/mmu: remove unused variable
  RISC-V: KVM: Add support for Svpbmt inside Guest/VM
  RISC-V: KVM: Use PAGE_KERNEL_IO in kvm_riscv_gstage_ioremap()
  RISC-V: KVM: Add G-stage ioremap() and iounmap() functions
  KVM: Add gfp_custom flag in struct kvm_mmu_memory_cache
  RISC-V: KVM: Add extensible CSR emulation framework
  RISC-V: KVM: Add extensible system instruction emulation framework
  RISC-V: KVM: Factor-out instruction emulation into separate sources
  RISC-V: KVM: move preempt_disable() call in kvm_arch_vcpu_ioctl_run
  RISC-V: KVM: Make kvm_riscv_guest_timer_init a void function
  RISC-V: KVM: Fix variable spelling mistake
  RISC-V: KVM: Improve ISA extension by using a bitmap
  KVM, x86/mmu: Fix the comment around kvm_tdp_mmu_zap_leafs()
  KVM: SVM: Dump Virtual Machine Save Area (VMSA) to klog
  KVM: x86/mmu: Treat NX as a valid SPTE bit for NPT
  KVM: x86: Do not block APIC write for non ICR registers
  ...
2022-08-04 14:59:54 -07:00
Linus Torvalds
e2b5421007 flexible-array transformations in UAPI for 6.0-rc1
Hi Linus,
 
 Please, pull the following treewide patch that replaces zero-length arrays
 with flexible-array members in UAPI. This patch has been baking in
 linux-next for 5 weeks now.
 
 -fstrict-flex-arrays=3 is coming and we need to land these changes
 to prevent issues like these in the short future:
 
 ../fs/minix/dir.c:337:3: warning: 'strcpy' will always overflow; destination buffer has size 0,
 but the source string has length 2 (including NUL byte) [-Wfortify-source]
 		strcpy(de3->name, ".");
 		^
 
 Since these are all [0] to [] changes, the risk to UAPI is nearly zero. If
 this breaks anything, we can use a union with a new member name.
 
 Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836
 
 Thanks
 --
 Gustavo
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEkmRahXBSurMIg1YvRwW0y0cG2zEFAmLoNdcACgkQRwW0y0cG
 2zEVeg//QYJ3j2pbKt9zB6muO3SkrNoMPc5wpY/SITUeiDscukLvGzJG88eIZskl
 NaEjbmacHmdlQrBkUdr10i1+hkb2zRd6/j42GIDXEhhKTMoT2UxJCBp47KSvd7VY
 dKNLGsgQs3kwmmxLEGu6w6vywWpI5wxXTKWL1Q/RpUXoOnLmsMEbzKTjf12a1Edl
 9gPNY+tMHIHyB0pGIRXDY/ZF5c+FcRFn6kKeMVzJL0bnX7FI4UmYe83k9ajEiLWA
 MD3JAw/mNv2X0nizHHuQHIjtky8Pr+E8hKs5ni88vMYmFqeABsTw4R1LJykv/mYa
 NakU1j9tHYTKcs2Ju+gIvSKvmatKGNmOpti/8RAjEX1YY4cHlHWNsigVbVRLqfo7
 SKImlSUxOPGFS3HAJQCC9P/oZgICkUdD6sdLO1PVBnE1G3Fvxg5z6fGcdEuEZkVR
 PQwlYDm1nlTuScbkgVSBzyU/AkntVMJTuPWgbpNo+VgSXWZ8T/U8II0eGrFVf9rH
 +y5dAS52/bi6OP0la7fNZlq7tcPfNG9HJlPwPb1kQtuPT4m6CBhth/rRrDJwx8za
 0cpJT75Q3CI0wLZ7GN4yEjtNQrlAeeiYiS4LMQ/SFFtg1KzvmYYVmWDhOf0+mMDA
 f7bq4cxEg2LHwrhRgQQWowFVBu7yeiwKbcj9sybfA27bMqCtfto=
 =8yMq
 -----END PGP SIGNATURE-----

Merge tag 'flexible-array-transformations-UAPI-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux

Pull uapi flexible array update from Gustavo Silva:
 "A treewide patch that replaces zero-length arrays with flexible-array
  members in UAPI. This has been baking in linux-next for 5 weeks now.

  '-fstrict-flex-arrays=3' is coming and we need to land these changes
  to prevent issues like these in the short future:

    fs/minix/dir.c:337:3: warning: 'strcpy' will always overflow; destination buffer has size 0, but the source string has length 2 (including NUL byte) [-Wfortify-source]
		strcpy(de3->name, ".");
		^

  Since these are all [0] to [] changes, the risk to UAPI is nearly
  zero. If this breaks anything, we can use a union with a new member
  name"

Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836

* tag 'flexible-array-transformations-UAPI-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux:
  treewide: uapi: Replace zero-length arrays with flexible-array members
2022-08-02 19:50:47 -07:00
Paolo Bonzini
63f4b21041 Merge remote-tracking branch 'kvm/next' into kvm-next-5.20
KVM/s390, KVM/x86 and common infrastructure changes for 5.20

x86:

* Permit guests to ignore single-bit ECC errors

* Fix races in gfn->pfn cache refresh; do not pin pages tracked by the cache

* Intel IPI virtualization

* Allow getting/setting pending triple fault with KVM_GET/SET_VCPU_EVENTS

* PEBS virtualization

* Simplify PMU emulation by just using PERF_TYPE_RAW events

* More accurate event reinjection on SVM (avoid retrying instructions)

* Allow getting/setting the state of the speaker port data bit

* Refuse starting the kvm-intel module if VM-Entry/VM-Exit controls are inconsistent

* "Notify" VM exit (detect microarchitectural hangs) for Intel

* Cleanups for MCE MSR emulation

s390:

* add an interface to provide a hypervisor dump for secure guests

* improve selftests to use TAP interface

* enable interpretive execution of zPCI instructions (for PCI passthrough)

* First part of deferred teardown

* CPU Topology

* PV attestation

* Minor fixes

Generic:

* new selftests API using struct kvm_vcpu instead of a (vm, id) tuple

x86:

* Use try_cmpxchg64 instead of cmpxchg64

* Bugfixes

* Ignore benign host accesses to PMU MSRs when PMU is disabled

* Allow disabling KVM's "MONITOR/MWAIT are NOPs!" behavior

* x86/MMU: Allow NX huge pages to be disabled on a per-vm basis

* Port eager page splitting to shadow MMU as well

* Enable CMCI capability by default and handle injected UCNA errors

* Expose pid of vcpu threads in debugfs

* x2AVIC support for AMD

* cleanup PIO emulation

* Fixes for LLDT/LTR emulation

* Don't require refcounted "struct page" to create huge SPTEs

x86 cleanups:

* Use separate namespaces for guest PTEs and shadow PTEs bitmasks

* PIO emulation

* Reorganize rmap API, mostly around rmap destruction

* Do not workaround very old KVM bugs for L0 that runs with nesting enabled

* new selftests API for CPUID
2022-08-01 03:21:00 -04:00
Anup Patel
8a061562e2 RISC-V: KVM: Add extensible CSR emulation framework
We add an extensible CSR emulation framework which is based upon the
existing system instruction emulation. This will be useful to upcoming
AIA, PMU, Nested and other virtualization features.

The CSR emulation framework also has provision to emulate CSR in user
space but this will be used only in very specific cases such as AIA
IMSIC CSR emulation in user space or vendor specific CSR emulation
in user space.

By default, all CSRs not handled by KVM RISC-V will be redirected back
to Guest VCPU as illegal instruction trap.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:53 +05:30
Pierre Morel
f5ecfee944 KVM: s390: resetting the Topology-Change-Report
During a subsystem reset the Topology-Change-Report is cleared.

Let's give userland the possibility to clear the MTCR in the case
of a subsystem reset.

To migrate the MTCR, we give userland the possibility to
query the MTCR state.

We indicate KVM support for the CPU topology facility with a new
KVM capability: KVM_CAP_S390_CPU_TOPOLOGY.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Message-Id: <20220714194334.127812-1-pmorel@linux.ibm.com>
Link: https://lore.kernel.org/all/20220714194334.127812-1-pmorel@linux.ibm.com/
[frankja@linux.ibm.com: Simple conflict resolution in Documentation/virt/kvm/api.rst]
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2022-07-20 10:57:37 +02:00
Oliver Upton
450a563924 KVM: stats: Fix value for KVM_STATS_UNIT_MAX for boolean stats
commit 1b870fa557 ("kvm: stats: tell userspace which values are
boolean") added a new stat unit (boolean) but failed to raise
KVM_STATS_UNIT_MAX.

Fix by pointing UNIT_MAX at the new max value of UNIT_BOOLEAN.

Fixes: 1b870fa557 ("kvm: stats: tell userspace which values are boolean")
Reported-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Signed-off-by: Oliver Upton <oupton@google.com>
Message-Id: <20220719125229.2934273-1-oupton@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-07-19 08:54:11 -04:00
Paolo Bonzini
1b870fa557 kvm: stats: tell userspace which values are boolean
Some of the statistics values exported by KVM are always only 0 or 1.
It can be useful to export this fact to userspace so that it can track
them specially (for example by polling the value every now and then to
compute a % of time spent in a specific state).

Therefore, add "boolean value" as a new "unit".  While it is not exactly
a unit, it walks and quacks like one.  In particular, using the type
would be wrong because boolean values could be instantaneous or peak
values (e.g. "is the rmap allocated?") or even two-bucket histograms
(e.g. "number of posted vs. non-posted interrupt injections").

Suggested-by: Amneesh Singh <natto@weirdnatto.in>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-07-14 08:01:59 -04:00
Christian Borntraeger
d41b5e0176 KVM: s390/pci: enable zPCI for interpretive execution
Add the necessary code in s390 base, pci and KVM to enable interpretion
 of PCI pasthru.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEE+SKTgaM0CPnbq/vKEXu8gLWmHHwFAmLL7HcACgkQEXu8gLWm
 HHz0JA/8C/pG5JdeOfKA6ZgWuUtxh8NRAmn+XEh+sAPpdK1cmEc1Qt/UKteSFel4
 cmqfaCELalq/BaFxtPS7Wn8Rf4pY8/GwEzwM0dNiS09pTWv0YMXql6+013nr1TJU
 hWx5Pm9Za+T/UnbbHqlyJfjMf7/HELHmQYemDpCr6n1sIYMjsWIJI/P6ZsQiG/8V
 iDZQGIM8mfUC+PMzxsYAQZQB3nm6noZfnWlAcuChDCmgk2ZxdXSdZlHneiLLiYlb
 yZPOyTysA0H2iFgRGfXMI4Oz6vegr6xAcZ2c9mkc8lM42yKHQNpPa0PqEY+EzVV8
 0iaMT3LKWQRdjzTq6E4I5wb74KQn/t1TbTzM5wznOQ6GySRhPvnXVLOuYyUf5d+0
 PwtnfKyx2C5UtOn47Xuujp5FClP8NI8Se5uq6Myei5OtYAvrQtOFxiJAixLx8nCb
 ca/migenYr+R5zYn5g3o6oo2BUJfF3Y1Q8nazz602JRu42aZzVFu2GNB062YjleK
 w7SfIZNTh0picxSmoehSOQMVaiGY/C/ow7Xa+bLaCITQC3s8HY73m3gynaVOB23X
 2umrC3HkTnH2ymqvDC6O/5QG7IUlSfjbWzN0TdmPfV5KeM7BmBvP4vxqxRYyTY7b
 7UhFg820fZKZu4Ul740a2+HBNw73T8fc4xbZVJ6glJo3AdWQD5s=
 =YD+W
 -----END PGP SIGNATURE-----

Merge tag 'kvm-s390-pci-5.20' into kernelorgnext

KVM: s390/pci: enable zPCI for interpretive execution

Add the necessary code in s390 base, pci and KVM to enable interpretion
of PCI pasthru.
2022-07-11 11:28:57 +02:00
Matthew Rosato
db1c875e05 KVM: s390: add KVM_S390_ZPCI_OP to manage guest zPCI devices
The KVM_S390_ZPCI_OP ioctl provides a mechanism for managing
hardware-assisted virtualization features for s390x zPCI passthrough.
Add the first 2 operations, which can be used to enable/disable
the specified device for Adapter Event Notification interpretation.

Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20220606203325.110625-21-mjrosato@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2022-07-11 09:54:38 +02:00
Gustavo A. R. Silva
94dfc73e7c treewide: uapi: Replace zero-length arrays with flexible-array members
There is a regular need in the kernel to provide a way to declare
having a dynamically sized set of trailing elements in a structure.
Kernel code should always use “flexible array members”[1] for these
cases. The older style of one-element or zero-length arrays should
no longer be used[2].

This code was transformed with the help of Coccinelle:
(linux-5.19-rc2$ spatch --jobs $(getconf _NPROCESSORS_ONLN) --sp-file script.cocci --include-headers --dir . > output.patch)

@@
identifier S, member, array;
type T1, T2;
@@

struct S {
  ...
  T1 member;
  T2 array[
- 0
  ];
};

-fstrict-flex-arrays=3 is coming and we need to land these changes
to prevent issues like these in the short future:

../fs/minix/dir.c:337:3: warning: 'strcpy' will always overflow; destination buffer has size 0,
but the source string has length 2 (including NUL byte) [-Wfortify-source]
		strcpy(de3->name, ".");
		^

Since these are all [0] to [] changes, the risk to UAPI is nearly zero. If
this breaks anything, we can use a union with a new member name.

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.16/process/deprecated.html#zero-length-and-one-element-arrays

Link: https://github.com/KSPP/linux/issues/78
Build-tested-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/lkml/62b675ec.wKX6AOZ6cbE71vtF%25lkp@intel.com/
Acked-by: Dan Williams <dan.j.williams@intel.com> # For ndctl.h
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2022-06-28 21:26:05 +02:00
Ben Gardon
084cc29f8b KVM: x86/MMU: Allow NX huge pages to be disabled on a per-vm basis
In some cases, the NX hugepage mitigation for iTLB multihit is not
needed for all guests on a host. Allow disabling the mitigation on a
per-VM basis to avoid the performance hit of NX hugepages on trusted
workloads.

In order to disable NX hugepages on a VM, ensure that the userspace
actor has permission to reboot the system. Since disabling NX hugepages
would allow a guest to crash the system, it is similar to reboot
permissions.

Ideally, KVM would require userspace to prove it has access to KVM's
nx_huge_pages module param, e.g. so that userspace can opt out without
needing full reboot permissions.  But getting access to the module param
file info is difficult because it is buried in layers of sysfs and module
glue. Requiring CAP_SYS_BOOT is sufficient for all known use cases.

Suggested-by: Jim Mattson <jmattson@google.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20220613212523.3436117-9-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-24 04:51:49 -04:00
Tao Xu
2f4073e08f KVM: VMX: Enable Notify VM exit
There are cases that malicious virtual machines can cause CPU stuck (due
to event windows don't open up), e.g., infinite loop in microcode when
nested #AC (CVE-2015-5307). No event window means no event (NMI, SMI and
IRQ) can be delivered. It leads the CPU to be unavailable to host or
other VMs.

VMM can enable notify VM exit that a VM exit generated if no event
window occurs in VM non-root mode for a specified amount of time (notify
window).

Feature enabling:
- The new vmcs field SECONDARY_EXEC_NOTIFY_VM_EXITING is introduced to
  enable this feature. VMM can set NOTIFY_WINDOW vmcs field to adjust
  the expected notify window.
- Add a new KVM capability KVM_CAP_X86_NOTIFY_VMEXIT so that user space
  can query and enable this feature in per-VM scope. The argument is a
  64bit value: bits 63:32 are used for notify window, and bits 31:0 are
  for flags. Current supported flags:
  - KVM_X86_NOTIFY_VMEXIT_ENABLED: enable the feature with the notify
    window provided.
  - KVM_X86_NOTIFY_VMEXIT_USER: exit to userspace once the exits happen.
- It's safe to even set notify window to zero since an internal hardware
  threshold is added to vmcs.notify_window.

VM exit handling:
- Introduce a vcpu state notify_window_exits to records the count of
  notify VM exits and expose it through the debugfs.
- Notify VM exit can happen incident to delivery of a vector event.
  Allow it in KVM.
- Exit to userspace unconditionally for handling when VM_CONTEXT_INVALID
  bit is set.

Nested handling
- Nested notify VM exits are not supported yet. Keep the same notify
  window control in vmcs02 as vmcs01, so that L1 can't escape the
  restriction of notify VM exits through launching L2 VM.

Notify VM exit is defined in latest Intel Architecture Instruction Set
Extensions Programming Reference, chapter 9.2.

Co-developed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Tao Xu <tao3.xu@intel.com>
Co-developed-by: Chenyi Qiang <chenyi.qiang@intel.com>
Signed-off-by: Chenyi Qiang <chenyi.qiang@intel.com>
Message-Id: <20220524135624.22988-5-chenyi.qiang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-08 05:56:24 -04:00
Chenyi Qiang
ed2351174e KVM: x86: Extend KVM_{G,S}ET_VCPU_EVENTS to support pending triple fault
For the triple fault sythesized by KVM, e.g. the RSM path or
nested_vmx_abort(), if KVM exits to userspace before the request is
serviced, userspace could migrate the VM and lose the triple fault.

Extend KVM_{G,S}ET_VCPU_EVENTS to support pending triple fault with a
new event KVM_VCPUEVENT_VALID_FAULT_FAULT so that userspace can save and
restore the triple fault event. This extension is guarded by a new KVM
capability KVM_CAP_TRIPLE_FAULT_EVENT.

Note that in the set_vcpu_events path, userspace is able to set/clear
the triple fault request through triple_fault.pending field.

Signed-off-by: Chenyi Qiang <chenyi.qiang@intel.com>
Message-Id: <20220524135624.22988-2-chenyi.qiang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-08 05:20:53 -04:00
Janosch Frank
e9bf3acb23 KVM: s390: Add KVM_CAP_S390_PROTECTED_DUMP
The capability indicates dump support for protected VMs.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20220517163629.3443-9-frankja@linux.ibm.com
Message-Id: <20220517163629.3443-9-frankja@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2022-06-01 16:57:14 +02:00
Janosch Frank
8aba09588d KVM: s390: Add CPU dump functionality
The previous patch introduced the per-VM dump functions now let's
focus on dumping the VCPU state via the newly introduced
KVM_S390_PV_CPU_COMMAND ioctl which mirrors the VM UV ioctl and can be
extended with new commands later.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20220517163629.3443-8-frankja@linux.ibm.com
Message-Id: <20220517163629.3443-8-frankja@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2022-06-01 16:57:14 +02:00
Janosch Frank
0460eb35b4 KVM: s390: Add configuration dump functionality
Sometimes dumping inside of a VM fails, is unavailable or doesn't
yield the required data. For these occasions we dump the VM from the
outside, writing memory and cpu data to a file.

Up to now PV guests only supported dumping from the inside of the
guest through dumpers like KDUMP. A PV guest can be dumped from the
hypervisor but the data will be stale and / or encrypted.

To get the actual state of the PV VM we need the help of the
Ultravisor who safeguards the VM state. New UV calls have been added
to initialize the dump, dump storage state data, dump cpu data and
complete the dump process. We expose these calls in this patch via a
new UV ioctl command.

The sensitive parts of the dump data are encrypted, the dump key is
derived from the Customer Communication Key (CCK). This ensures that
only the owner of the VM who has the CCK can decrypt the dump data.

The memory is dumped / read via a normal export call and a re-import
after the dump initialization is not needed (no re-encryption with a
dump key).

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20220517163629.3443-7-frankja@linux.ibm.com
Message-Id: <20220517163629.3443-7-frankja@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2022-06-01 16:57:14 +02:00
Janosch Frank
fe9a93e07b KVM: s390: pv: Add query dump information
The dump API requires userspace to provide buffers into which we will
store data. The dump information added in this patch tells userspace
how big those buffers need to be.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Link: https://lore.kernel.org/r/20220517163629.3443-6-frankja@linux.ibm.com
Message-Id: <20220517163629.3443-6-frankja@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2022-06-01 16:57:14 +02:00
Janosch Frank
35d02493db KVM: s390: pv: Add query interface
Some of the query information is already available via sysfs but
having a IOCTL makes the information easier to retrieve.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Link: https://lore.kernel.org/r/20220517163629.3443-4-frankja@linux.ibm.com
Message-Id: <20220517163629.3443-4-frankja@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2022-06-01 16:57:14 +02:00
Paolo Bonzini
47e8eec832 KVM/arm64 updates for 5.19
- Add support for the ARMv8.6 WFxT extension
 
 - Guard pages for the EL2 stacks
 
 - Trap and emulate AArch32 ID registers to hide unsupported features
 
 - Ability to select and save/restore the set of hypercalls exposed
   to the guest
 
 - Support for PSCI-initiated suspend in collaboration with userspace
 
 - GICv3 register-based LPI invalidation support
 
 - Move host PMU event merging into the vcpu data structure
 
 - GICv3 ITS save/restore fixes
 
 - The usual set of small-scale cleanups and fixes
 -----BEGIN PGP SIGNATURE-----
 
 iQJDBAABCgAtFiEEn9UcU+C1Yxj9lZw9I9DQutE9ekMFAmKGAGsPHG1hekBrZXJu
 ZWwub3JnAAoJECPQ0LrRPXpDB/gQAMhyZ+wCG0OMEZhwFF6iDfxVEX2Kw8L41NtD
 a/e6LDWuIOGihItpRkYROc5myG74D7XckF2Bz3G7HJoU4vhwHOV/XulE26GFizoC
 O1GVRekeSUY81wgS1yfo0jojLupBkTjiq3SjTHoDP7GmCM0qDPBtA0QlMRzd2bMs
 Kx0+UUXZUHFSTXc7Lp4vqNH+tMp7se+yRx7hxm6PCM5zG+XYJjLxnsZ0qpchObgU
 7f6YFojsLUs1SexgiUqJ1RChVQ+FkgICh5HyzORvGtHNNzK6D2sIbsW6nqMGAMql
 Kr3A5O/VOkCztSYnLxaa76/HqD21mvUrXvr3grhabNc7rOmuzWV0dDgr6c6wHKHb
 uNCtH4d7Ra06gUrEOrfsgLOLn0Zqik89y6aIlMsnTudMg9gMNgFHy1jz4LM7vMkY
 FS5AVj059heg2uJcfgTvzzcqneyuBLBmF3dS4coowO6oaj8SycpaEmP5e89zkPMI
 1kk8d0e6RmXuCh/2AJ8GxxnKvBPgqp2mMKXOCJ8j4AmHEDX/CKpEBBqIWLKkplUU
 8DGiOWJUtRZJg398dUeIpiVLoXJthMODjAnkKkuhiFcQbXomlwgg7YSnNAz6TRED
 Z7KR2leC247kapHnnagf02q2wED8pBeyrxbQPNdrHtSJ9Usm4nTkY443HgVTJW3s
 aTwPZAQ7
 =mh7W
 -----END PGP SIGNATURE-----

Merge tag 'kvmarm-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 updates for 5.19

- Add support for the ARMv8.6 WFxT extension

- Guard pages for the EL2 stacks

- Trap and emulate AArch32 ID registers to hide unsupported features

- Ability to select and save/restore the set of hypercalls exposed
  to the guest

- Support for PSCI-initiated suspend in collaboration with userspace

- GICv3 register-based LPI invalidation support

- Move host PMU event merging into the vcpu data structure

- GICv3 ITS save/restore fixes

- The usual set of small-scale cleanups and fixes

[Due to the conflict, KVM_SYSTEM_EVENT_SEV_TERM is relocated
 from 4 to 6. - Paolo]
2022-05-25 05:09:23 -04:00
Oliver Upton
bfbab44568 KVM: arm64: Implement PSCI SYSTEM_SUSPEND
ARM DEN0022D.b 5.19 "SYSTEM_SUSPEND" describes a PSCI call that allows
software to request that a system be placed in the deepest possible
low-power state. Effectively, software can use this to suspend itself to
RAM.

Unfortunately, there really is no good way to implement a system-wide
PSCI call in KVM. Any precondition checks done in the kernel will need
to be repeated by userspace since there is no good way to protect a
critical section that spans an exit to userspace. SYSTEM_RESET and
SYSTEM_OFF are equally plagued by this issue, although no users have
seemingly cared for the relatively long time these calls have been
supported.

The solution is to just make the whole implementation userspace's
problem. Introduce a new system event, KVM_SYSTEM_EVENT_SUSPEND, that
indicates to userspace a calling vCPU has invoked PSCI SYSTEM_SUSPEND.
Additionally, add a CAP to get buy-in from userspace for this new exit
type.

Only advertise the SYSTEM_SUSPEND PSCI call if userspace has opted in.
If a vCPU calls SYSTEM_SUSPEND, punt straight to userspace. Provide
explicit documentation of userspace's responsibilites for the exit and
point to the PSCI specification to describe the actual PSCI call.

Reviewed-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Oliver Upton <oupton@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220504032446.4133305-8-oupton@google.com
2022-05-04 09:28:45 +01:00
Oliver Upton
7b33a09d03 KVM: arm64: Add support for userspace to suspend a vCPU
Introduce a new MP state, KVM_MP_STATE_SUSPENDED, which indicates a vCPU
is in a suspended state. In the suspended state the vCPU will block
until a wakeup event (pending interrupt) is recognized.

Add a new system event type, KVM_SYSTEM_EVENT_WAKEUP, to indicate to
userspace that KVM has recognized one such wakeup event. It is the
responsibility of userspace to then make the vCPU runnable, or leave it
suspended until the next wakeup event.

Signed-off-by: Oliver Upton <oupton@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220504032446.4133305-7-oupton@google.com
2022-05-04 09:28:45 +01:00
Paolo Bonzini
71d7c575a6 Merge branch 'kvm-fixes-for-5.18-rc5' into HEAD
Fixes for (relatively) old bugs, to be merged in both the -rc and next
development trees.

The merge reconciles the ABI fixes for KVM_EXIT_SYSTEM_EVENT between
5.18 and commit c24a950ec7 ("KVM, SEV: Add KVM_EXIT_SHUTDOWN metadata
for SEV-ES", 2022-04-13).
2022-04-29 12:47:59 -04:00
Paolo Bonzini
d495f942f4 KVM: fix bad user ABI for KVM_EXIT_SYSTEM_EVENT
When KVM_EXIT_SYSTEM_EVENT was introduced, it included a flags
member that at the time was unused.  Unfortunately this extensibility
mechanism has several issues:

- x86 is not writing the member, so it would not be possible to use it
  on x86 except for new events

- the member is not aligned to 64 bits, so the definition of the
  uAPI struct is incorrect for 32- on 64-bit userspace.  This is a
  problem for RISC-V, which supports CONFIG_KVM_COMPAT, but fortunately
  usage of flags was only introduced in 5.18.

Since padding has to be introduced, place a new field in there
that tells if the flags field is valid.  To allow further extensibility,
in fact, change flags to an array of 16 values, and store how many
of the values are valid.  The availability of the new ndata field
is tied to a system capability; all architectures are changed to
fill in the field.

To avoid breaking compilation of userspace that was using the flags
field, provide a userspace-only union to overlap flags with data[0].
The new field is placed at the same offset for both 32- and 64-bit
userspace.

Cc: Will Deacon <will@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Peter Gonda <pgonda@google.com>
Cc: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reported-by: kernel test robot <lkp@intel.com>
Message-Id: <20220422103013.34832-1-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-29 12:38:22 -04:00
Peter Gonda
c24a950ec7 KVM, SEV: Add KVM_EXIT_SHUTDOWN metadata for SEV-ES
If an SEV-ES guest requests termination, exit to userspace with
KVM_EXIT_SYSTEM_EVENT and a dedicated SEV_TERM type instead of -EINVAL
so that userspace can take appropriate action.

See AMD's GHCB spec section '4.1.13 Termination Request' for more details.

Suggested-by: Sean Christopherson <seanjc@google.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Peter Gonda <pgonda@google.com>

Reported-by: kernel test robot <lkp@intel.com>
Message-Id: <20220407210233.782250-1-pgonda@google.com>
[Add documentatino. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-13 13:37:46 -04:00
David Woodhouse
ffbb61d09f KVM: x86: Accept KVM_[GS]ET_TSC_KHZ as a VM ioctl.
This sets the default TSC frequency for subsequently created vCPUs.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20220225145304.36166-2-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-02 05:41:19 -04:00
David Woodhouse
661a20fab7 KVM: x86/xen: Advertise and document KVM_XEN_HVM_CONFIG_EVTCHN_SEND
At the end of the patch series adding this batch of event channel
acceleration features, finally add the feature bit which advertises
them and document it all.

For SCHEDOP_poll we need to wake a polling vCPU when a given port
is triggered, even when it's masked — and we want to implement that
in the kernel, for efficiency. So we want the kernel to know that it
has sole ownership of event channel delivery. Thus, we allow
userspace to make the 'promise' by setting the corresponding feature
bit in its KVM_XEN_HVM_CONFIG call. As we implement SCHEDOP_poll
bypass later, we will do so only if that promise has been made by
userspace.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220303154127.202856-16-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-02 05:41:17 -04:00
David Woodhouse
fde0451be8 KVM: x86/xen: Support per-vCPU event channel upcall via local APIC
Windows uses a per-vCPU vector, and it's delivered via the local APIC
basically like an MSI (with associated EOI) unlike the traditional
guest-wide vector which is just magically asserted by Xen (and in the
KVM case by kvm_xen_has_interrupt() / kvm_cpu_get_extint()).

Now that the kernel is able to raise event channel events for itself,
being able to do so for Windows guests is also going to be useful.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220303154127.202856-15-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-02 05:41:17 -04:00
David Woodhouse
28d1629f75 KVM: x86/xen: Kernel acceleration for XENVER_version
Turns out this is a fast path for PV guests because they use it to
trigger the event channel upcall. So letting it bounce all the way up
to userspace is not great.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220303154127.202856-14-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-02 05:41:16 -04:00
Joao Martins
5363952605 KVM: x86/xen: handle PV timers oneshot mode
If the guest has offloaded the timer virq, handle the following
hypercalls for programming the timer:

    VCPUOP_set_singleshot_timer
    VCPUOP_stop_singleshot_timer
    set_timer_op(timestamp_ns)

The event channel corresponding to the timer virq is then used to inject
events once timer deadlines are met. For now we back the PV timer with
hrtimer.

[ dwmw2: Add save/restore, 32-bit compat mode, immediate delivery,
         don't check timer in kvm_vcpu_has_event() ]

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220303154127.202856-13-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-02 05:41:16 -04:00
David Woodhouse
942c2490c2 KVM: x86/xen: Add KVM_XEN_VCPU_ATTR_TYPE_VCPU_ID
In order to intercept hypercalls such as VCPUOP_set_singleshot_timer, we
need to be aware of the Xen CPU numbering.

This looks a lot like the Hyper-V handling of vpidx, for obvious reasons.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220303154127.202856-12-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-02 05:41:15 -04:00
Joao Martins
2fd6df2f2b KVM: x86/xen: intercept EVTCHNOP_send from guests
Userspace registers a sending @port to either deliver to an @eventfd
or directly back to a local event channel port.

After binding events the guest or host may wish to bind those
events to a particular vcpu. This is usually done for unbound
and and interdomain events. Update requests are handled via the
KVM_XEN_EVTCHN_UPDATE flag.

Unregistered ports are handled by the emulator.

Co-developed-by: Ankur Arora <ankur.a.arora@oracle.com>
Co-developed-By: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220303154127.202856-10-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-02 05:41:15 -04:00
David Woodhouse
35025735a7 KVM: x86/xen: Support direct injection of event channel events
This adds a KVM_XEN_HVM_EVTCHN_SEND ioctl which allows direct injection
of events given an explicit { vcpu, port, priority } in precisely the
same form that those fields are given in the IRQ routing table.

Userspace is currently able to inject 2-level events purely by setting
the bits in the shared_info and vcpu_info, but FIFO event channels are
harder to deal with; we will need the kernel to take sole ownership of
delivery when we support those.

A patch advertising this feature with a new bit in the KVM_CAP_XEN_HVM
ioctl will be added in a subsequent patch.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220303154127.202856-9-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-02 05:41:14 -04:00
Oliver Upton
6d8491910f KVM: x86: Introduce KVM_CAP_DISABLE_QUIRKS2
KVM_CAP_DISABLE_QUIRKS is irrevocably broken. The capability does not
advertise the set of quirks which may be disabled to userspace, so it is
impossible to predict the behavior of KVM. Worse yet,
KVM_CAP_DISABLE_QUIRKS will tolerate any value for cap->args[0], meaning
it fails to reject attempts to set invalid quirk bits.

The only valid workaround for the quirky quirks API is to add a new CAP.
Actually advertise the set of quirks that can be disabled to userspace
so it can predict KVM's behavior. Reject values for cap->args[0] that
contain invalid bits.

Finally, add documentation for the new capability and describe the
existing quirks.

Signed-off-by: Oliver Upton <oupton@google.com>
Message-Id: <20220301060351.442881-5-oupton@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-03-21 09:28:41 -04:00
David Dunn
ba7bb663f5 KVM: x86: Provide per VM capability for disabling PMU virtualization
Add a new capability, KVM_CAP_PMU_CAPABILITY, that takes a bitmask of
settings/features to allow userspace to configure PMU virtualization on
a per-VM basis.  For now, support a single flag, KVM_PMU_CAP_DISABLE,
to allow disabling PMU virtualization for a VM even when KVM is configured
with enable_pmu=true a module level.

To keep KVM simple, disallow changing VM's PMU configuration after vCPUs
have been created.

Signed-off-by: David Dunn <daviddunn@google.com>
Message-Id: <20220223225743.2703915-2-daviddunn@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-02-25 08:20:14 -05:00
Paolo Bonzini
4dfc4ec2b7 Merge branch 'kvm-ppc-cap-210' into kvm-next-5.18 2022-02-24 08:49:56 -05:00
Nicholas Piggin
93b71801a8 KVM: PPC: reserve capability 210 for KVM_CAP_PPC_AIL_MODE_3
Add KVM_CAP_PPC_AIL_MODE_3 to advertise the capability to set the AIL
resource mode to 3 with the H_SET_MODE hypercall. This capability
differs between processor types and KVM types (PR, HV, Nested HV), and
affects guest-visible behaviour.

QEMU will implement a cap-ail-mode-3 to control this behaviour[1], and
use the KVM CAP if available to determine KVM support[2].

Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-02-22 09:06:54 -05:00
Janis Schoetterl-Glausch
5e35d0eb47 KVM: s390: Update api documentation for memop ioctl
Document all currently existing operations, flags and explain under
which circumstances they are available. Document the recently
introduced absolute operations and the storage key protection flag,
as well as the existing SIDA operations.

Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20220211182215.2730017-10-scgl@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2022-02-14 16:12:57 +01:00
Janis Schoetterl-Glausch
d004079edc KVM: s390: Add capability for storage key extension of MEM_OP IOCTL
Availability of the KVM_CAP_S390_MEM_OP_EXTENSION capability signals that:
* The vcpu MEM_OP IOCTL supports storage key checking.
* The vm MEM_OP IOCTL exists.

Signed-off-by: Janis Schoetterl-Glausch <scgl@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/20220211182215.2730017-9-scgl@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2022-02-14 16:12:57 +01:00
Janis Schoetterl-Glausch
ef11c9463a KVM: s390: Add vm IOCTL for key checked guest absolute memory access
Channel I/O honors storage keys and is performed on absolute memory.
For I/O emulation user space therefore needs to be able to do key
checked accesses.
The vm IOCTL supports read/write accesses, as well as checking
if an access would succeed.
Unlike relying on KVM_S390_GET_SKEYS for key checking would,
the vm IOCTL performs the check in lockstep with the read or write,
by, ultimately, mapping the access to move instructions that
support key protection checking with a supplied key.
Fetch and storage protection override are not applicable to absolute
accesses and so are not applied as they are when using the vcpu memop.

Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Link: https://lore.kernel.org/r/20220211182215.2730017-7-scgl@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2022-02-14 16:12:57 +01:00
Janis Schoetterl-Glausch
e9e9feebcb KVM: s390: Add optional storage key checking to MEMOP IOCTL
User space needs a mechanism to perform key checked accesses when
emulating instructions.

The key can be passed as an additional argument.
Having an additional argument is flexible, as user space can
pass the guest PSW's key, in order to make an access the same way the
CPU would, or pass another key if necessary.

Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20220211182215.2730017-6-scgl@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2022-02-14 16:12:57 +01:00
Janosch Frank
f6c6804c43 kvm: Move KVM_GET_XSAVE2 IOCTL definition at the end of kvm.h
This way we can more easily find the next free IOCTL number when
adding new IOCTLs.

Fixes: be50b2065d ("kvm: x86: Add support for getting/setting expanded xstate buffer")
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Message-Id: <20220128154025.102666-1-frankja@linux.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-31 09:21:56 -05:00
Paolo Bonzini
dd6e631220 KVM: x86: add system attribute to retrieve full set of supported xsave states
Because KVM_GET_SUPPORTED_CPUID is meant to be passed (by simple-minded
VMMs) to KVM_SET_CPUID2, it cannot include any dynamic xsave states that
have not been enabled.  Probing those, for example so that they can be
passed to ARCH_REQ_XCOMP_GUEST_PERM, requires a new ioctl or arch_prctl.
The latter is in fact worse, even though that is what the rest of the
API uses, because it would require supported_xcr0 to be moved from the
KVM module to the kernel just for this use.  In addition, the value
would be nonsensical (or an error would have to be returned) until
the KVM module is loaded in.

Therefore, to limit the growth of system ioctls, add a /dev/kvm
variant of KVM_{GET,HAS}_DEVICE_ATTR, and implement it in x86
with just one group (0) and attribute (KVM_X86_XCOMP_GUEST_SUPP).

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-28 07:33:32 -05:00
Guang Zeng
be50b2065d kvm: x86: Add support for getting/setting expanded xstate buffer
With KVM_CAP_XSAVE, userspace uses a hardcoded 4KB buffer to get/set
xstate data from/to KVM. This doesn't work when dynamic xfeatures
(e.g. AMX) are exposed to the guest as they require a larger buffer
size.

Introduce a new capability (KVM_CAP_XSAVE2). Userspace VMM gets the
required xstate buffer size via KVM_CHECK_EXTENSION(KVM_CAP_XSAVE2).
KVM_SET_XSAVE is extended to work with both legacy and new capabilities
by doing properly-sized memdup_user() based on the guest fpu container.
KVM_GET_XSAVE is kept for backward-compatible reason. Instead,
KVM_GET_XSAVE2 is introduced under KVM_CAP_XSAVE2 as the preferred
interface for getting xstate buffer (4KB or larger size) from KVM
(Link: https://lkml.org/lkml/2021/12/15/510)

Also, update the api doc with the new KVM_GET_XSAVE2 ioctl.

Signed-off-by: Guang Zeng <guang.zeng@intel.com>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Jing Liu <jing2.liu@intel.com>
Signed-off-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Message-Id: <20220105123532.12586-19-yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-14 13:44:41 -05:00
David Woodhouse
14243b3871 KVM: x86/xen: Add KVM_IRQ_ROUTING_XEN_EVTCHN and event channel delivery
This adds basic support for delivering 2 level event channels to a guest.

Initially, it only supports delivery via the IRQ routing table, triggered
by an eventfd. In order to do so, it has a kvm_xen_set_evtchn_fast()
function which will use the pre-mapped shared_info page if it already
exists and is still valid, while the slow path through the irqfd_inject
workqueue will remap the shared_info page if necessary.

It sets the bits in the shared_info page but not the vcpu_info; that is
deferred to __kvm_xen_has_interrupt() which raises the vector to the
appropriate vCPU.

Add a 'verbose' mode to xen_shinfo_test while adding test cases for this.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20211210163625.2886-5-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-07 10:44:45 -05:00
Anup Patel
a457fd5660 RISC-V: KVM: Add VM capability to allow userspace get GPA bits
The number of GPA bits supported for a RISC-V Guest/VM is based on the
MMU mode used by the G-stage translation. The KVM RISC-V will detect and
use the best possible MMU mode for the G-stage in kvm_arch_init().

We add a generic VM capability KVM_CAP_VM_GPA_BITS which can be used by
the KVM userspace to get the number of GPA (guest physical address) bits
supported for a Guest/VM.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-and-tested-by: Atish Patra <atishp@rivosinc.com>
2022-01-06 15:16:58 +05:30
Peter Gonda
b56639318b KVM: SEV: Add support for SEV intra host migration
For SEV to work with intra host migration, contents of the SEV info struct
such as the ASID (used to index the encryption key in the AMD SP) and
the list of memory regions need to be transferred to the target VM.
This change adds a commands for a target VMM to get a source SEV VM's sev
info.

Signed-off-by: Peter Gonda <pgonda@google.com>
Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Marc Orr <marcorr@google.com>
Cc: Marc Orr <marcorr@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Message-Id: <20211021174303.385706-3-pgonda@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-11 10:35:27 -05:00
David Edmondson
e615e35589 KVM: x86: On emulation failure, convey the exit reason, etc. to userspace
Should instruction emulation fail, include the VM exit reason, etc. in
the emulation_failure data passed to userspace, in order that the VMM
can report it as a debugging aid when describing the failure.

Suggested-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: David Edmondson <david.edmondson@oracle.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210920103737.2696756-4-david.edmondson@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-25 06:48:24 -04:00
David Edmondson
a9d496d8e0 KVM: x86: Clarify the kvm_run.emulation_failure structure layout
Until more flags for kvm_run.emulation_failure flags are defined, it
is undetermined whether new payload elements corresponding to those
flags will be additive or alternative. As a hint to userspace that an
alternative is possible, wrap the current payload elements in a union.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Edmondson <david.edmondson@oracle.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210920103737.2696756-2-david.edmondson@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-25 06:48:24 -04:00
Oliver Upton
c68dc1b577 KVM: x86: Report host tsc and realtime values in KVM_GET_CLOCK
Handling the migration of TSCs correctly is difficult, in part because
Linux does not provide userspace with the ability to retrieve a (TSC,
realtime) clock pair for a single instant in time. In lieu of a more
convenient facility, KVM can report similar information in the kvm_clock
structure.

Provide userspace with a host TSC & realtime pair iff the realtime clock
is based on the TSC. If userspace provides KVM_SET_CLOCK with a valid
realtime value, advance the KVM clock by the amount of elapsed time. Do
not step the KVM clock backwards, though, as it is a monotonic
oscillator.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Oliver Upton <oupton@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210916181538.968978-5-oupton@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-18 14:43:44 -04:00
Atish Patra
dea8ee31a0 RISC-V: KVM: Add SBI v0.1 support
The KVM host kernel is running in HS-mode needs so we need to handle
the SBI calls coming from guest kernel running in VS-mode.

This patch adds SBI v0.1 support in KVM RISC-V. Almost all SBI v0.1
calls are implemented in KVM kernel module except GETCHAR and PUTCHART
calls which are forwarded to user space because these calls cannot be
implemented in kernel space. In future, when we implement SBI v0.2 for
Guest, we will forward SBI v0.2 experimental and vendor extension calls
to user space.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-10-04 16:11:30 +05:30