Commit Graph

365 Commits

Author SHA1 Message Date
Bagas Sanjaya
19a7cc817a KVM: x86/MMU: properly format KVM_CAP_VM_DISABLE_NX_HUGE_PAGES capability table
There is unexpected warning on KVM_CAP_VM_DISABLE_NX_HUGE_PAGES capability
table, which cause the table to be rendered as paragraph text instead.

The warning is due to missing colon at capability name and returns keyword,
as well as improper alignment on multi-line returns field.

Fix the warning by adding missing colons and aligning the field.

Link: https://lore.kernel.org/lkml/20220627181937.3be67263@canb.auug.org.au/
Fixes: 084cc29f8b ("KVM: x86/MMU: Allow NX huge pages to be disabled on a per-vm basis")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: David Matlack <dmatlack@google.com>
Cc: Ben Gardon <bgardon@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: kvm@vger.kernel.org
Cc: linux-next@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Message-Id: <20220627095151.19339-3-bagasdotme@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-08-11 02:35:37 -04:00
Bagas Sanjaya
b4aed4d85f Documentation: KVM: extend KVM_CAP_VM_DISABLE_NX_HUGE_PAGES heading underline
Extend heading underline for KVM_CAP_VM_DISABLE_NX_HUGE_PAGE to match
the heading text length.

Link: https://lore.kernel.org/lkml/20220627181937.3be67263@canb.auug.org.au/
Fixes: 084cc29f8b ("KVM: x86/MMU: Allow NX huge pages to be disabled on a per-vm basis")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: David Matlack <dmatlack@google.com>
Cc: Ben Gardon <bgardon@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: kvm@vger.kernel.org
Cc: linux-next@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Message-Id: <20220627095151.19339-2-bagasdotme@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-08-11 02:35:36 -04:00
Linus Torvalds
7c5c3a6177 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
aad26f55f4 Merge tag 'docs-6.0' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
 "This was a moderately busy cycle for documentation, but nothing
  all that earth-shaking:

   - More Chinese translations, and an update to the Italian
     translations.

     The Japanese, Korean, and traditional Chinese translations
     are more-or-less unmaintained at this point, instead.

   - Some build-system performance improvements.

   - The removal of the archaic submitting-drivers.rst document,
     with the movement of what useful material that remained into
     other docs.

   - Improvements to sphinx-pre-install to, hopefully, give more
     useful suggestions.

   - A number of build-warning fixes

  Plus the usual collection of typo fixes, updates, and more"

* tag 'docs-6.0' of git://git.lwn.net/linux: (92 commits)
  docs: efi-stub: Fix paths for x86 / arm stubs
  Docs/zh_CN: Update the translation of sched-stats to 5.19-rc8
  Docs/zh_CN: Update the translation of pci to 5.19-rc8
  Docs/zh_CN: Update the translation of pci-iov-howto to 5.19-rc8
  Docs/zh_CN: Update the translation of usage to 5.19-rc8
  Docs/zh_CN: Update the translation of testing-overview to 5.19-rc8
  Docs/zh_CN: Update the translation of sparse to 5.19-rc8
  Docs/zh_CN: Update the translation of kasan to 5.19-rc8
  Docs/zh_CN: Update the translation of iio_configfs to 5.19-rc8
  doc:it_IT: align Italian documentation
  docs: Remove spurious tag from admin-guide/mm/overcommit-accounting.rst
  Documentation: process: Update email client instructions for Thunderbird
  docs: ABI: correct QEMU fw_cfg spec path
  doc/zh_CN: remove submitting-driver reference from docs
  docs: zh_TW: align to submitting-drivers removal
  docs: zh_CN: align to submitting-drivers removal
  docs: ko_KR: howto: remove reference to removed submitting-drivers
  docs: ja_JP: howto: remove reference to removed submitting-drivers
  docs: it_IT: align to submitting-drivers removal
  docs: process: remove outdated submitting-drivers.rst
  ...
2022-08-02 19:24:24 -07:00
Linus Torvalds
0cec3f24a7 Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
 "Highlights include a major rework of our kPTI page-table rewriting
  code (which makes it both more maintainable and considerably faster in
  the cases where it is required) as well as significant changes to our
  early boot code to reduce the need for data cache maintenance and
  greatly simplify the KASLR relocation dance.

  Summary:

   - Remove unused generic cpuidle support (replaced by PSCI version)

   - Fix documentation describing the kernel virtual address space

   - Handling of some new CPU errata in Arm implementations

   - Rework of our exception table code in preparation for handling
     machine checks (i.e. RAS errors) more gracefully

   - Switch over to the generic implementation of ioremap()

   - Fix lockdep tracking in NMI context

   - Instrument our memory barrier macros for KCSAN

   - Rework of the kPTI G->nG page-table repainting so that the MMU
     remains enabled and the boot time is no longer slowed to a crawl
     for systems which require the late remapping

   - Enable support for direct swapping of 2MiB transparent huge-pages
     on systems without MTE

   - Fix handling of MTE tags with allocating new pages with HW KASAN

   - Expose the SMIDR register to userspace via sysfs

   - Continued rework of the stack unwinder, particularly improving the
     behaviour under KASAN

   - More repainting of our system register definitions to match the
     architectural terminology

   - Improvements to the layout of the vDSO objects

   - Support for allocating additional bits of HWCAP2 and exposing
     FEAT_EBF16 to userspace on CPUs that support it

   - Considerable rework and optimisation of our early boot code to
     reduce the need for cache maintenance and avoid jumping in and out
     of the kernel when handling relocation under KASLR

   - Support for disabling SVE and SME support on the kernel
     command-line

   - Support for the Hisilicon HNS3 PMU

   - Miscellanous cleanups, trivial updates and minor fixes"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (136 commits)
  arm64: Delay initialisation of cpuinfo_arm64::reg_{zcr,smcr}
  arm64: fix KASAN_INLINE
  arm64/hwcap: Support FEAT_EBF16
  arm64/cpufeature: Store elf_hwcaps as a bitmap rather than unsigned long
  arm64/hwcap: Document allocation of upper bits of AT_HWCAP
  arm64: enable THP_SWAP for arm64
  arm64/mm: use GENMASK_ULL for TTBR_BADDR_MASK_52
  arm64: errata: Remove AES hwcap for COMPAT tasks
  arm64: numa: Don't check node against MAX_NUMNODES
  drivers/perf: arm_spe: Fix consistency of SYS_PMSCR_EL1.CX
  perf: RISC-V: Add of_node_put() when breaking out of for_each_of_cpu_node()
  docs: perf: Include hns3-pmu.rst in toctree to fix 'htmldocs' WARNING
  arm64: kasan: Revert "arm64: mte: reset the page tag in page->flags"
  mm: kasan: Skip page unpoisoning only if __GFP_SKIP_KASAN_UNPOISON
  mm: kasan: Skip unpoisoning of user pages
  mm: kasan: Ensure the tags are visible before the tag in page->flags
  drivers/perf: hisi: add driver for HNS3 PMU
  drivers/perf: hisi: Add description for HNS3 PMU driver
  drivers/perf: riscv_pmu_sbi: perf format
  perf/arm-cci: Use the bitmap API to allocate bitmaps
  ...
2022-08-01 10:37:00 -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
Paolo Bonzini
a4850b5590 Merge tag 'kvm-s390-next-5.20-1' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
KVM: s390x: Fixes and features for 5.20

* First part of deferred teardown
* CPU Topology
* interpretive execution for PCI instructions
* PV attestation
* Minor fixes
2022-07-22 03:14:32 -04:00
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
942d9e8952 Documentation: kvm: clarify histogram units
In the case of histogram statistics, the values are always sample
counts; the unit instead applies to the bucket range.  For example,
halt_poll_success_hist is a nanosecond statistic because the buckets are
for 0ns, 1ns, 2-3ns, 4-7ns etc.  There isn't really any other sensible
interpretation, but clarify this anyway in the Documentation.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-07-14 08:02:09 -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
Sean Christopherson
43bb9e000e KVM: x86: Tweak name of MONITOR/MWAIT #UD quirk to make it #UD specific
Add a "UD" clause to KVM_X86_QUIRK_MWAIT_NEVER_FAULTS to make it clear
that the quirk only controls the #UD behavior of MONITOR/MWAIT.  KVM
doesn't currently enforce fault checks when MONITOR/MWAIT are supported,
but that could change in the future.  SVM also has a virtualization hole
in that it checks all faults before intercepts, and so "never faults" is
already a lie when running on SVM.

Fixes: bfbcc81bb8 ("KVM: x86: Add a quirk for KVM's "MONITOR/MWAIT are NOPs!" behavior")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220711225753.1073989-4-seanjc@google.com
2022-07-13 18:14:05 -07:00
Michael Kelley
ab3e69fc4d Documentation: hyperv: Add overview of clocks and timers
Add documentation topic for clocks and timers when running as a
guest on Hyper-V.

Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/1657561704-12631-4-git-send-email-mikelley@microsoft.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-07-13 14:04:48 -06:00
Michael Kelley
ac1129e79e Documentation: hyperv: Add overview of VMbus
Add documentation topic for using VMbus when running as a guest
on Hyper-V.

Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/1657561704-12631-3-git-send-email-mikelley@microsoft.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-07-13 14:04:48 -06:00
Michael Kelley
ec7c56812f Documentation: hyperv: Add overview of Hyper-V enlightenments
Add an initial documentation topic for Linux enlightenments to
run as a guest on Microsoft's Hyper-V hypervisor, linked under
the "virt" documentation area. Update the virt doc index.rst
and the MAINTAINERS file.

Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/1657561704-12631-2-git-send-email-mikelley@microsoft.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-07-13 14:04:48 -06:00
Bagas Sanjaya
5efab5cdf0 Documentation: kvm: extend KVM_S390_ZPCI_OP subheading underline
Stephen Rothwell reported the htmldocs warning:

Documentation/virt/kvm/api.rst:5959: WARNING: Title underline too short.

4.137 KVM_S390_ZPCI_OP
--------------------

The warning is due to subheading underline on KVM_S390_ZPCI_OP section is
short of 2 dashes.

Extend the underline to fix the warning.

Link: https://lore.kernel.org/linux-next/20220711205557.183c3b14@canb.auug.org.au/
Fixes: a0c4d1109d6cc5 ("KVM: s390: add KVM_S390_ZPCI_OP to manage guest zPCI devices")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Pierre Morel <pmorel@linux.ibm.com>
Cc: Thomas Huth <thuth@redhat.com>
Cc: Matthew Rosato <mjrosato@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: kvm@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://lore.kernel.org/r/20220712092954.142027-4-bagasdotme@gmail.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2022-07-13 10:10:11 +02:00
Christian Borntraeger
d41b5e0176 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
Mauro Carvalho Chehab
8a5d192166 Documentation: KVM: update s390-diag.rst reference
Changeset daec8d4083 ("Documentation: KVM: add separate directories for architecture-specific documentation")
renamed: Documentation/virt/kvm/s390-diag.rst
to: Documentation/virt/kvm/s390/s390-diag.rst.

Update its cross-reference accordingly.

Fixes: daec8d4083 ("Documentation: KVM: add separate directories for architecture-specific documentation")
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Link: https://lore.kernel.org/r/85b81e4678bbe23d0e9692616798762a6465f0a3.1656234456.git.mchehab@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-07-07 13:10:00 -06:00
Mauro Carvalho Chehab
48b36e59ac Documentation: KVM: update msr.rst reference
Changeset daec8d4083 ("Documentation: KVM: add separate directories for architecture-specific documentation")
renamed: Documentation/virt/kvm/msr.rst
to: Documentation/virt/kvm/x86/msr.rst.

Update its cross-reference accordingly.

Fixes: daec8d4083 ("Documentation: KVM: add separate directories for architecture-specific documentation")
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Link: https://lore.kernel.org/r/5652b7f5caff3b817a660b75f1f319a2f8962380.1656234456.git.mchehab@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-07-07 13:09:59 -06:00
Mauro Carvalho Chehab
7ac3945d8e Documentation: KVM: update amd-memory-encryption.rst references
Changeset daec8d4083 ("Documentation: KVM: add separate directories for architecture-specific documentation")
renamed: Documentation/virt/kvm/amd-memory-encryption.rst
to: Documentation/virt/kvm/x86/amd-memory-encryption.rst.

Update the cross-references accordingly.

Fixes: daec8d4083 ("Documentation: KVM: add separate directories for architecture-specific documentation")
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Link: https://lore.kernel.org/r/fd80db889e34aae87a4ca88cad94f650723668f4.1656234456.git.mchehab@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-07-07 13:09:59 -06:00
Mauro Carvalho Chehab
e38fd63749 Documentation: KVM: update s390-pv.rst reference
Changesets: daec8d4083 ("Documentation: KVM: add separate directories for architecture-specific documentation")
and: daec8d4083 ("Documentation: KVM: add separate directories for architecture-specific documentation")
renamed: Documentation/virt/kvm/s390-pv.rst
to: Documentation/virt/kvm/s390/s390-pv.rst.

Update its cross-reference accordingly.

Fixes: daec8d4083 ("Documentation: KVM: add separate directories for architecture-specific documentation")
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Link: https://lore.kernel.org/r/e2676f087d287db0bc31ae7c05c80ce5adf93333.1656234456.git.mchehab@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-07-07 13:09:59 -06:00
Marc Zyngier
7ddb0c3df7 arm64: Rename the VHE switch to "finalise_el2"
as we are about to perform a lot more in 'mutate_to_vhe' than
we currently do, this function really becomes the point where
we finalise the basic EL2 configuration.

Reflect this into the code by renaming a bunch of things:
- HVC_VHE_RESTART -> HVC_FINALISE_EL2
- switch_to_vhe --> finalise_el2
- mutate_to_vhe -> __finalise_el2

No functional changes.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220630160500.1536744-2-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-07-01 15:22:51 +01:00
Steven Lung
5b8d9ee003 docs: UML: fix typo
Replace 'absense' with 'absence'.

Signed-off-by: Steven Lung <1030steven@gmail.com>
Link: https://lore.kernel.org/r/20220621072910.4704-1-1030steven@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-06-24 13:18:21 -06:00
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