Commit Graph

305 Commits

Author SHA1 Message Date
Stephen Rothwell
582eb04e05 Documentation: KVM: Fix title level for PSCI_SUSPEND
The htmldoc build breaks in a funny way with:

<quote>
Sphinx parallel build error:
docutils.utils.SystemMessage: /home/sfr/next/next/Documentation/virt/kvm/api.rst:6175: (SEVERE/4) Title level inconsistent:

For arm/arm64:
^^^^^^^^^^^^^^
</quote>

Swap the ^^s for a bunch of --s...

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
[maz: commit message]
Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-05 12:24:21 +01:00
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
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
Like Xu
af105c9cc9 Documentation: KVM: Add SPDX-License-Identifier tag
+new file mode 100644
+WARNING: Missing or malformed SPDX-License-Identifier tag in line 1
+#27: FILE: Documentation/virt/kvm/x86/errata.rst:1:

Opportunistically update all other non-added KVM documents and
remove a new extra blank line at EOF for x86/errata.rst.

Signed-off-by: Like Xu <likexu@tencent.com>
Message-Id: <20220406063715.55625-5-likexu@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-11 13:28:56 -04:00
Bagas Sanjaya
c1be1ef1b4 Documentation: kvm: Add missing line break in api.rst
Add missing line break separator between literal block and description
of KVM_EXIT_RISCV_SBI.

This fixes:
</path/to/linux>/Documentation/virt/kvm/api.rst:6118: WARNING: Literal block ends without a blank line; unexpected unindent.

Fixes: da40d85805 (RISC-V: KVM: Document RISC-V specific parts of KVM API, 2021-09-27)
Cc: Anup Patel <anup.patel@wdc.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-riscv@lists.infradead.org
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Message-Id: <20220403065735.23859-1-bagasdotme@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-05 08:11:37 -04:00
Linus Torvalds
38904911e8 * Only do MSR filtering for MSRs accessed by rdmsr/wrmsr
* Documentation improvements
 
 * Prevent module exit until all VMs are freed
 
 * PMU Virtualization fixes
 
 * Fix for kvm_irq_delivery_to_apic_fast() NULL-pointer dereferences
 
 * Other miscellaneous bugfixes
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:

 - Only do MSR filtering for MSRs accessed by rdmsr/wrmsr

 - Documentation improvements

 - Prevent module exit until all VMs are freed

 - PMU Virtualization fixes

 - Fix for kvm_irq_delivery_to_apic_fast() NULL-pointer dereferences

 - Other miscellaneous bugfixes

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (42 commits)
  KVM: x86: fix sending PV IPI
  KVM: x86/mmu: do compare-and-exchange of gPTE via the user address
  KVM: x86: Remove redundant vm_entry_controls_clearbit() call
  KVM: x86: cleanup enter_rmode()
  KVM: x86: SVM: fix tsc scaling when the host doesn't support it
  kvm: x86: SVM: remove unused defines
  KVM: x86: SVM: move tsc ratio definitions to svm.h
  KVM: x86: SVM: fix avic spec based definitions again
  KVM: MIPS: remove reference to trap&emulate virtualization
  KVM: x86: document limitations of MSR filtering
  KVM: x86: Only do MSR filtering when access MSR by rdmsr/wrmsr
  KVM: x86/emulator: Emulate RDPID only if it is enabled in guest
  KVM: x86/pmu: Fix and isolate TSX-specific performance event logic
  KVM: x86: mmu: trace kvm_mmu_set_spte after the new SPTE was set
  KVM: x86/svm: Clear reserved bits written to PerfEvtSeln MSRs
  KVM: x86: Trace all APICv inhibit changes and capture overall status
  KVM: x86: Add wrappers for setting/clearing APICv inhibits
  KVM: x86: Make APICv inhibit reasons an enum and cleanup naming
  KVM: X86: Handle implicit supervisor access with SMAP
  KVM: X86: Rename variable smap to not_smap in permission_fault()
  ...
2022-04-02 12:09:02 -07:00
Paolo Bonzini
fe5f691413 KVM: MIPS: remove reference to trap&emulate virtualization
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220313140522.1307751-1-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-02 05:34:47 -04:00
Paolo Bonzini
ce2f72e26c KVM: x86: document limitations of MSR filtering
MSR filtering requires an exit to userspace that is hard to implement and
would be very slow in the case of nested VMX vmexit and vmentry MSR
accesses.  Document the limitation.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-02 05:34:47 -04:00
David Woodhouse
cf1d88b36b KVM: Remove dirty handling from gfn_to_pfn_cache completely
It isn't OK to cache the dirty status of a page in internal structures
for an indefinite period of time.

Any time a vCPU exits the run loop to userspace might be its last; the
VMM might do its final check of the dirty log, flush the last remaining
dirty pages to the destination and complete a live migration. If we
have internal 'dirty' state which doesn't get flushed until the vCPU
is finally destroyed on the source after migration is complete, then
we have lost data because that will escape the final copy.

This problem already exists with the use of kvm_vcpu_unmap() to mark
pages dirty in e.g. VMX nesting.

Note that the actual Linux MM already considers the page to be dirty
since we have a writeable mapping of it. This is just about the KVM
dirty logging.

For the nesting-style use cases (KVM_GUEST_USES_PFN) we will need to
track which gfn_to_pfn_caches have been used and explicitly mark the
corresponding pages dirty before returning to userspace. But we would
have needed external tracking of that anyway, rather than walking the
full list of GPCs to find those belonging to this vCPU which are dirty.

So let's rely *solely* on that external tracking, and keep it simple
rather than laying a tempting trap for callers to fall into.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220303154127.202856-3-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-02 05:34:41 -04:00
Sean Christopherson
df06dae3f2 KVM: Don't actually set a request when evicting vCPUs for GFN cache invd
Don't actually set a request bit in vcpu->requests when making a request
purely to force a vCPU to exit the guest.  Logging a request but not
actually consuming it would cause the vCPU to get stuck in an infinite
loop during KVM_RUN because KVM would see the pending request and bail
from VM-Enter to service the request.

Note, it's currently impossible for KVM to set KVM_REQ_GPC_INVALIDATE as
nothing in KVM is wired up to set guest_uses_pa=true.  But, it'd be all
too easy for arch code to introduce use of kvm_gfn_to_pfn_cache_init()
without implementing handling of the request, especially since getting
test coverage of MMU notifier interaction with specific KVM features
usually requires a directed test.

Opportunistically rename gfn_to_pfn_cache_invalidate_start()'s wake_vcpus
to evict_vcpus.  The purpose of the request is to get vCPUs out of guest
mode, it's supposed to _avoid_ waking vCPUs that are blocking.

Opportunistically rename KVM_REQ_GPC_INVALIDATE to be more specific as to
what it wants to accomplish, and to genericize the name so that it can
used for similar but unrelated scenarios, should they arise in the future.
Add a comment and documentation to explain why the "no action" request
exists.

Add compile-time assertions to help detect improper usage.  Use the inner
assertless helper in the one s390 path that makes requests without a
hardcoded request.

Cc: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220223165302.3205276-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-02 05:34:39 -04:00
Linus Torvalds
e8b767f5e0 This pull request contains the following changes for UML:
- Devicetree support (for testing)
 - Various cleanups and fixes: UBD, port_user, uml_mconsole
 - Maintainer update
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Merge tag 'for-linus-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml

Pull UML updates from Richard Weinberger:

 - Devicetree support (for testing)

 - Various cleanups and fixes: UBD, port_user, uml_mconsole

 - Maintainer update

* tag 'for-linus-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: run_helper: Write error message to kernel log on exec failure on host
  um: port_user: Improve error handling when port-helper is not found
  um: port_user: Allow setting path to port-helper using UML_PORT_HELPER envvar
  um: port_user: Search for in.telnetd in PATH
  um: clang: Strip out -mno-global-merge from USER_CFLAGS
  docs: UML: Mention telnetd for port channel
  um: Remove unused timeval_to_ns() function
  um: Fix uml_mconsole stop/go
  um: Cleanup syscall_handler_t definition/cast, fix warning
  uml: net: vector: fix const issue
  um: Fix WRITE_ZEROES in the UBD Driver
  um: Migrate vector drivers to NAPI
  um: Fix order of dtb unflatten/early init
  um: fix and optimize xor select template for CONFIG64 and timetravel mode
  um: Document dtb command line option
  lib/logic_iomem: correct fallback config references
  um: Remove duplicated include in syscalls_64.c
  MAINTAINERS: Update UserModeLinux entry
2022-03-31 16:16:58 -07:00
Paolo Bonzini
cde363ab7c Documentation: KVM: add API issues section
Add a section to document all the different ways in which the KVM API sucks.

I am sure there are way more, give people a place to vent so that userspace
authors are aware.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220322110712.222449-4-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-03-29 13:21:20 -04:00
Paolo Bonzini
45016721de Documentation: KVM: add virtual CPU errata documentation
Add a file to document all the different ways in which the virtual CPU
emulation is imperfect.  Include an example to show how to document
such errata.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Oliver Upton <oupton@google.com>
Message-Id: <20220322110712.222449-3-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-03-29 13:21:20 -04:00
Paolo Bonzini
daec8d4083 Documentation: KVM: add separate directories for architecture-specific documentation
ARM already has an arm/ subdirectory, but s390 and x86 do not even though
they have a relatively large number of files specific to them.  Create
new directories in Documentation/virt/kvm for these two architectures
as well.

While at it, group the API documentation and the developer documentation
in the table of contents.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220322110712.222449-2-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-03-29 13:21:20 -04:00
Paolo Bonzini
99a17b7770 Documentation: kvm: include new locks
kvm->mn_invalidate_lock and kvm->slots_arch_lock were not included in the
documentation, add them.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220322110720.222499-3-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-03-29 13:21:19 -04:00
Paolo Bonzini
e9611bf9d2 Documentation: kvm: fixes for locking.rst
Separate the various locks clearly, and include the new names of blocked_vcpu_on_cpu_lock
and blocked_vcpu_on_cpu.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220322110720.222499-2-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-03-29 13:21:19 -04:00
Linus Torvalds
1ebdbeb03e ARM:
- Proper emulation of the OSLock feature of the debug architecture
 
 - Scalibility improvements for the MMU lock when dirty logging is on
 
 - New VMID allocator, which will eventually help with SVA in VMs
 
 - Better support for PMUs in heterogenous systems
 
 - PSCI 1.1 support, enabling support for SYSTEM_RESET2
 
 - Implement CONFIG_DEBUG_LIST at EL2
 
 - Make CONFIG_ARM64_ERRATUM_2077057 default y
 
 - Reduce the overhead of VM exit when no interrupt is pending
 
 - Remove traces of 32bit ARM host support from the documentation
 
 - Updated vgic selftests
 
 - Various cleanups, doc updates and spelling fixes
 
 RISC-V:
 
 - Prevent KVM_COMPAT from being selected
 
 - Optimize __kvm_riscv_switch_to() implementation
 
 - RISC-V SBI v0.3 support
 
 s390:
 
 - memop selftest
 
 - fix SCK locking
 
 - adapter interruptions virtualization for secure guests
 
 - add Claudio Imbrenda as maintainer
 
 - first step to do proper storage key checking
 
 x86:
 
 - Continue switching kvm_x86_ops to static_call(); introduce
   static_call_cond() and __static_call_ret0 when applicable.
 
 - Cleanup unused arguments in several functions
 
 - Synthesize AMD 0x80000021 leaf
 
 - Fixes and optimization for Hyper-V sparse-bank hypercalls
 
 - Implement Hyper-V's enlightened MSR bitmap for nested SVM
 
 - Remove MMU auditing
 
 - Eager splitting of page tables (new aka "TDP" MMU only) when dirty
   page tracking is enabled
 
 - Cleanup the implementation of the guest PGD cache
 
 - Preparation for the implementation of Intel IPI virtualization
 
 - Fix some segment descriptor checks in the emulator
 
 - Allow AMD AVIC support on systems with physical APIC ID above 255
 
 - Better API to disable virtualization quirks
 
 - Fixes and optimizations for the zapping of page tables:
 
   - Zap roots in two passes, avoiding RCU read-side critical sections
     that last too long for very large guests backed by 4 KiB SPTEs.
 
   - Zap invalid and defunct roots asynchronously via concurrency-managed
     work queue.
 
   - Allowing yielding when zapping TDP MMU roots in response to the root's
     last reference being put.
 
   - Batch more TLB flushes with an RCU trick.  Whoever frees the paging
     structure now holds RCU as a proxy for all vCPUs running in the guest,
     i.e. to prolongs the grace period on their behalf.  It then kicks the
     the vCPUs out of guest mode before doing rcu_read_unlock().
 
 Generic:
 
 - Introduce __vcalloc and use it for very large allocations that
   need memcg accounting
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "ARM:
   - Proper emulation of the OSLock feature of the debug architecture

   - Scalibility improvements for the MMU lock when dirty logging is on

   - New VMID allocator, which will eventually help with SVA in VMs

   - Better support for PMUs in heterogenous systems

   - PSCI 1.1 support, enabling support for SYSTEM_RESET2

   - Implement CONFIG_DEBUG_LIST at EL2

   - Make CONFIG_ARM64_ERRATUM_2077057 default y

   - Reduce the overhead of VM exit when no interrupt is pending

   - Remove traces of 32bit ARM host support from the documentation

   - Updated vgic selftests

   - Various cleanups, doc updates and spelling fixes

  RISC-V:
   - Prevent KVM_COMPAT from being selected

   - Optimize __kvm_riscv_switch_to() implementation

   - RISC-V SBI v0.3 support

  s390:
   - memop selftest

   - fix SCK locking

   - adapter interruptions virtualization for secure guests

   - add Claudio Imbrenda as maintainer

   - first step to do proper storage key checking

  x86:
   - Continue switching kvm_x86_ops to static_call(); introduce
     static_call_cond() and __static_call_ret0 when applicable.

   - Cleanup unused arguments in several functions

   - Synthesize AMD 0x80000021 leaf

   - Fixes and optimization for Hyper-V sparse-bank hypercalls

   - Implement Hyper-V's enlightened MSR bitmap for nested SVM

   - Remove MMU auditing

   - Eager splitting of page tables (new aka "TDP" MMU only) when dirty
     page tracking is enabled

   - Cleanup the implementation of the guest PGD cache

   - Preparation for the implementation of Intel IPI virtualization

   - Fix some segment descriptor checks in the emulator

   - Allow AMD AVIC support on systems with physical APIC ID above 255

   - Better API to disable virtualization quirks

   - Fixes and optimizations for the zapping of page tables:

      - Zap roots in two passes, avoiding RCU read-side critical
        sections that last too long for very large guests backed by 4
        KiB SPTEs.

      - Zap invalid and defunct roots asynchronously via
        concurrency-managed work queue.

      - Allowing yielding when zapping TDP MMU roots in response to the
        root's last reference being put.

      - Batch more TLB flushes with an RCU trick. Whoever frees the
        paging structure now holds RCU as a proxy for all vCPUs running
        in the guest, i.e. to prolongs the grace period on their behalf.
        It then kicks the the vCPUs out of guest mode before doing
        rcu_read_unlock().

  Generic:
   - Introduce __vcalloc and use it for very large allocations that need
     memcg accounting"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (246 commits)
  KVM: use kvcalloc for array allocations
  KVM: x86: Introduce KVM_CAP_DISABLE_QUIRKS2
  kvm: x86: Require const tsc for RT
  KVM: x86: synthesize CPUID leaf 0x80000021h if useful
  KVM: x86: add support for CPUID leaf 0x80000021
  KVM: x86: do not use KVM_X86_OP_OPTIONAL_RET0 for get_mt_mask
  Revert "KVM: x86/mmu: Zap only TDP MMU leafs in kvm_zap_gfn_range()"
  kvm: x86/mmu: Flush TLB before zap_gfn_range releases RCU
  KVM: arm64: fix typos in comments
  KVM: arm64: Generalise VM features into a set of flags
  KVM: s390: selftests: Add error memop tests
  KVM: s390: selftests: Add more copy memop tests
  KVM: s390: selftests: Add named stages for memop test
  KVM: s390: selftests: Add macro as abstraction for MEM_OP
  KVM: s390: selftests: Split memop tests
  KVM: s390x: fix SCK locking
  RISC-V: KVM: Implement SBI HSM suspend call
  RISC-V: KVM: Add common kvm_riscv_vcpu_wfi() function
  RISC-V: Add SBI HSM suspend related defines
  RISC-V: KVM: Implement SBI v0.3 SRST extension
  ...
2022-03-24 11:58:57 -07:00
Linus Torvalds
346658a5e1 It has been a moderately busy cycle for documentation; some of the
highlights are:
 
 - Numerous PDF-generation improvements
 
 - Kees's new document with guidelines for researchers studying the
   development community.
 
 - The ongoing stream of Chinese translations
 
 - Thorsten's new document on regression handling
 
 - A major reworking of the internal documentation for the kernel-doc
   script.
 
 Plus the usual stream of typo fixes and such.
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Merge tag 'docs-5.18' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "It has been a moderately busy cycle for documentation; some of the
  highlights are:

   - Numerous PDF-generation improvements

   - Kees's new document with guidelines for researchers studying the
     development community.

   - The ongoing stream of Chinese translations

   - Thorsten's new document on regression handling

   - A major reworking of the internal documentation for the kernel-doc
     script.

  Plus the usual stream of typo fixes and such"

* tag 'docs-5.18' of git://git.lwn.net/linux: (80 commits)
  docs/kernel-parameters: update description of mem=
  docs/zh_CN: Add sched-nice-design Chinese translation
  docs: scheduler: Convert schedutil.txt to ReST
  Docs: ktap: add code-block type
  docs: serial: fix a reference file name in driver.rst
  docs: UML: Mention telnetd for port channel
  docs/zh_CN: add damon reclaim translation
  docs/zh_CN: add damon usage translation
  docs/zh_CN: add admin-guide damon start translation
  docs/zh_CN: add admin-guide damon index translation
  docs/zh_CN: Refactoring the admin-guide directory index
  zh_CN: Add translation for admin-guide/mm/index.rst
  zh_CN: Add translations for admin-guide/mm/ksm.rst
  Add Chinese translation for vm/ksm.rst
  docs/zh_CN: Add sched-stats Chinese translation
  docs/zh_CN: add devicetree of_unittest translation
  docs/zh_CN: add devicetree usage-model translation
  docs/zh_CN: add devicetree index translation
  Documentation: describe how to apply incremental stable patches
  docs/zh_CN: add peci subsystem translation
  ...
2022-03-21 14:13:25 -07:00
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
Paolo Bonzini
714797c98e KVM/arm64 updates for 5.18
- Proper emulation of the OSLock feature of the debug architecture
 
 - Scalibility improvements for the MMU lock when dirty logging is on
 
 - New VMID allocator, which will eventually help with SVA in VMs
 
 - Better support for PMUs in heterogenous systems
 
 - PSCI 1.1 support, enabling support for SYSTEM_RESET2
 
 - Implement CONFIG_DEBUG_LIST at EL2
 
 - Make CONFIG_ARM64_ERRATUM_2077057 default y
 
 - Reduce the overhead of VM exit when no interrupt is pending
 
 - Remove traces of 32bit ARM host support from the documentation
 
 - Updated vgic selftests
 
 - Various cleanups, doc updates and spelling fixes
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Merge tag 'kvmarm-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 updates for 5.18

- Proper emulation of the OSLock feature of the debug architecture

- Scalibility improvements for the MMU lock when dirty logging is on

- New VMID allocator, which will eventually help with SVA in VMs

- Better support for PMUs in heterogenous systems

- PSCI 1.1 support, enabling support for SYSTEM_RESET2

- Implement CONFIG_DEBUG_LIST at EL2

- Make CONFIG_ARM64_ERRATUM_2077057 default y

- Reduce the overhead of VM exit when no interrupt is pending

- Remove traces of 32bit ARM host support from the documentation

- Updated vgic selftests

- Various cleanups, doc updates and spelling fixes
2022-03-18 12:43:24 -04:00
Vincent Whitchurch
89ee9301ac docs: UML: Mention telnetd for port channel
It is not obvious from the documentation that using the "port" channel
for the console requires telnetd to be installed (see port_connection()
in arch/um/drivers/port_user.c).  Mention this, and the fact that UML
will not boot until a client connects.

Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Acked-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Link: https://lore.kernel.org/r/20220310124230.3069354-1-vincent.whitchurch@axis.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-03-11 13:51:03 -07:00
Vincent Whitchurch
4ef5a0b2e1 docs: UML: Mention telnetd for port channel
It is not obvious from the documentation that using the "port" channel
for the console requires telnetd to be installed (see port_connection()
in arch/um/drivers/port_user.c).  Mention this, and the fact that UML
will not boot until a client connects.

Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Acked-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-03-11 10:50:42 +01:00
Anton Ivanov
6427c16527 um: Document dtb command line option
Add documentation for the dtb command line option and the
ability to load/parse device trees.

Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Reviewed-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-03-11 10:43:32 +01:00
Marc Zyngier
7297a8bcc0 Merge branch kvm-arm64/misc-5.18 into kvmarm-master/next
* kvm-arm64/misc-5.18:
  : .
  : Misc fixes for KVM/arm64 5.18:
  :
  : - Drop unused kvm parameter to kvm_psci_version()
  :
  : - Implement CONFIG_DEBUG_LIST at EL2
  :
  : - Make CONFIG_ARM64_ERRATUM_2077057 default y
  :
  : - Only do the interrupt dance if we have exited because of an interrupt
  :
  : - Remove traces of 32bit ARM host support from the documentation
  : .
  Documentation: KVM: Update documentation to indicate KVM is arm64-only
  KVM: arm64: Only open the interrupt window on exit due to an interrupt
  KVM: arm64: Enable Cortex-A510 erratum 2077057 by default

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-03-09 11:16:48 +00:00
Oliver Upton
3fbf4207dc Documentation: KVM: Update documentation to indicate KVM is arm64-only
KVM support for 32-bit ARM hosts (KVM/arm) has been removed from the
kernel since commit 541ad0150c ("arm: Remove 32bit KVM host
support"). There still exists some remnants of the old architecture in
the KVM documentation.

Remove all traces of 32-bit host support from the documentation. Note
that AArch32 guests are still supported.

Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Oliver Upton <oupton@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220308172856.2997250-1-oupton@google.com
2022-03-09 11:15:24 +00:00
Paolo Bonzini
0564eeb71b Merge branch 'kvm-bugfixes' into HEAD
Merge bugfixes from 5.17 before merging more tricky work.
2022-03-04 18:39:29 -05:00
Sean Christopherson
e65a3b46b5 KVM: Drop KVM_REQ_MMU_RELOAD and update vcpu-requests.rst documentation
Remove the now unused KVM_REQ_MMU_RELOAD, shift KVM_REQ_VM_DEAD into the
unoccupied space, and update vcpu-requests.rst, which was missing an
entry for KVM_REQ_VM_DEAD.  Switching KVM_REQ_VM_DEAD to entry '1' also
fixes the stale comment about bits 4-7 being reserved.

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Ben Gardon <bgardon@google.com>
Message-Id: <20220225182248.3812651-7-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-03-01 08:58:26 -05:00
Marc Zyngier
1a48ce9264 Merge branch kvm-arm64/psci-1.1 into kvmarm-master/next
* kvm-arm64/psci-1.1:
  : .
  : Limited PSCI-1.1 support from Will Deacon:
  :
  : This small series exposes the PSCI SYSTEM_RESET2 call to guests, which
  : allows the propagation of a "reset_type" and a "cookie" back to the VMM.
  : Although Linux guests only ever pass 0 for the type ("SYSTEM_WARM_RESET"),
  : the vendor-defined range can be used by a bootloader to provide additional
  : information about the reset, such as an error code.
  : .
  KVM: arm64: Remove unneeded semicolons
  KVM: arm64: Indicate SYSTEM_RESET2 in kvm_run::system_event flags field
  KVM: arm64: Expose PSCI SYSTEM_RESET2 call to the guest
  KVM: arm64: Bump guest PSCI version to 1.1

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-02-25 13:49:48 +00:00
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
Paolo Bonzini
1e2277ed70 Merge branch 'kvm-ppc-cap-210' into kvm-master
By request of Nick Piggin:

> Patch 3 requires a KVM_CAP_PPC number allocated. QEMU maintainers are
> happy with it (link in changelog) just waiting on KVM upstreaming. Do
> you have objections to the series going to ppc/kvm tree first, or
> another option is you could take patch 3 alone first (it's relatively
> independent of the other 2) and ppc/kvm gets it from you?
2022-02-22 09:07:16 -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
cbf9b8109d KVM: s390: Clarify key argument for MEM_OP in api docs
Clarify that the key argument represents the access key, not the whole
storage key.

Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Link: https://lore.kernel.org/r/20220221143657.3712481-1-scgl@linux.ibm.com
Fixes: 5e35d0eb47 ("KVM: s390: Update api documentation for memop ioctl")
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2022-02-22 09:16:18 +01:00
Will Deacon
34739fd95f KVM: arm64: Indicate SYSTEM_RESET2 in kvm_run::system_event flags field
When handling reset and power-off PSCI calls from the guest, we
initialise X0 to PSCI_RET_INTERNAL_FAILURE in case the VMM tries to
re-run the vCPU after issuing the call.

Unfortunately, this also means that the VMM cannot see which PSCI call
was issued and therefore cannot distinguish between PSCI SYSTEM_RESET
and SYSTEM_RESET2 calls, which is necessary in order to determine the
validity of the "reset_type" in X1.

Allocate bit 0 of the previously unused 'flags' field of the
system_event structure so that we can indicate the PSCI call used to
initiate the reset.

Cc: Marc Zyngier <maz@kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Alexandru Elisei <alexandru.elisei@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220221153524.15397-4-will@kernel.org
2022-02-21 16:02:55 +00:00
Aaron Lewis
127770ac0d KVM: x86: Add KVM_CAP_ENABLE_CAP to x86
Follow the precedent set by other architectures that support the VCPU
ioctl, KVM_ENABLE_CAP, and advertise the VM extension, KVM_CAP_ENABLE_CAP.
This way, userspace can ensure that KVM_ENABLE_CAP is available on a
vcpu before using it.

Fixes: 5c919412fe ("kvm/x86: Hyper-V synthetic interrupt controller")
Signed-off-by: Aaron Lewis <aaronlewis@google.com>
Message-Id: <20220214212950.1776943-1-aaronlewis@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-02-17 09:52:50 -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
Alexandru Elisei
583cda1b0e KVM: arm64: Refuse to run VCPU if the PMU doesn't match the physical CPU
Userspace can assign a PMU to a VCPU with the KVM_ARM_VCPU_PMU_V3_SET_PMU
device ioctl. If the VCPU is scheduled on a physical CPU which has a
different PMU, the perf events needed to emulate a guest PMU won't be
scheduled in and the guest performance counters will stop counting. Treat
it as an userspace error and refuse to run the VCPU in this situation.

Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220127161759.53553-7-alexandru.elisei@arm.com
2022-02-08 17:51:22 +00:00
Alexandru Elisei
6ee7fca2a4 KVM: arm64: Add KVM_ARM_VCPU_PMU_V3_SET_PMU attribute
When KVM creates an event and there are more than one PMUs present on the
system, perf_init_event() will go through the list of available PMUs and
will choose the first one that can create the event. The order of the PMUs
in this list depends on the probe order, which can change under various
circumstances, for example if the order of the PMU nodes change in the DTB
or if asynchronous driver probing is enabled on the kernel command line
(with the driver_async_probe=armv8-pmu option).

Another consequence of this approach is that on heteregeneous systems all
virtual machines that KVM creates will use the same PMU. This might cause
unexpected behaviour for userspace: when a VCPU is executing on the
physical CPU that uses this default PMU, PMU events in the guest work
correctly; but when the same VCPU executes on another CPU, PMU events in
the guest will suddenly stop counting.

Fortunately, perf core allows user to specify on which PMU to create an
event by using the perf_event_attr->type field, which is used by
perf_init_event() as an index in the radix tree of available PMUs.

Add the KVM_ARM_VCPU_PMU_V3_CTRL(KVM_ARM_VCPU_PMU_V3_SET_PMU) VCPU
attribute to allow userspace to specify the arm_pmu that KVM will use when
creating events for that VCPU. KVM will make no attempt to run the VCPU on
the physical CPUs that share the PMU, leaving it up to userspace to manage
the VCPU threads' affinity accordingly.

To ensure that KVM doesn't expose an asymmetric system to the guest, the
PMU set for one VCPU will be used by all other VCPUs. Once a VCPU has run,
the PMU cannot be changed in order to avoid changing the list of available
events for a VCPU, or to change the semantics of existing events.

Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220127161759.53553-6-alexandru.elisei@arm.com
2022-02-08 17:51:21 +00:00
Marc Zyngier
5177fe91e4 KVM: arm64: Do not change the PMU event filter after a VCPU has run
Userspace can specify which events a guest is allowed to use with the
KVM_ARM_VCPU_PMU_V3_FILTER attribute. The list of allowed events can be
identified by a guest from reading the PMCEID{0,1}_EL0 registers.

Changing the PMU event filter after a VCPU has run can cause reads of the
registers performed before the filter is changed to return different values
than reads performed with the new event filter in place. The architecture
defines the two registers as read-only, and this behaviour contradicts
that.

Keep track when the first VCPU has run and deny changes to the PMU event
filter to prevent this from happening.

Signed-off-by: Marc Zyngier <maz@kernel.org>
[ Alexandru E: Added commit message, updated ioctl documentation ]
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220127161759.53553-2-alexandru.elisei@arm.com
2022-02-08 17:51:21 +00:00
Linus Torvalds
3cd7cd8a62 Two larger x86 series:
* Redo incorrect fix for SEV/SMAP erratum
 
 * Windows 11 Hyper-V workaround
 
 Other x86 changes:
 
 * Various x86 cleanups
 
 * Re-enable access_tracking_perf_test
 
 * Fix for #GP handling on SVM
 
 * Fix for CPUID leaf 0Dh in KVM_GET_SUPPORTED_CPUID
 
 * Fix for ICEBP in interrupt shadow
 
 * Avoid false-positive RCU splat
 
 * Enable Enlightened MSR-Bitmap support for real
 
 ARM:
 
 * Correctly update the shadow register on exception injection when
 running in nVHE mode
 
 * Correctly use the mm_ops indirection when performing cache invalidation
 from the page-table walker
 
 * Restrict the vgic-v3 workaround for SEIS to the two known broken
 implementations
 
 Generic code changes:
 
 * Dead code cleanup
 
 There will be another pull request for ARM fixes next week, but
 those patches need a bit more soak time.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:
 "Two larger x86 series:

   - Redo incorrect fix for SEV/SMAP erratum

   - Windows 11 Hyper-V workaround

  Other x86 changes:

   - Various x86 cleanups

   - Re-enable access_tracking_perf_test

   - Fix for #GP handling on SVM

   - Fix for CPUID leaf 0Dh in KVM_GET_SUPPORTED_CPUID

   - Fix for ICEBP in interrupt shadow

   - Avoid false-positive RCU splat

   - Enable Enlightened MSR-Bitmap support for real

  ARM:

   - Correctly update the shadow register on exception injection when
     running in nVHE mode

   - Correctly use the mm_ops indirection when performing cache
     invalidation from the page-table walker

   - Restrict the vgic-v3 workaround for SEIS to the two known broken
     implementations

  Generic code changes:

   - Dead code cleanup"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (43 commits)
  KVM: eventfd: Fix false positive RCU usage warning
  KVM: nVMX: Allow VMREAD when Enlightened VMCS is in use
  KVM: nVMX: Implement evmcs_field_offset() suitable for handle_vmread()
  KVM: nVMX: Rename vmcs_to_field_offset{,_table}
  KVM: nVMX: eVMCS: Filter out VM_EXIT_SAVE_VMX_PREEMPTION_TIMER
  KVM: nVMX: Also filter MSR_IA32_VMX_TRUE_PINBASED_CTLS when eVMCS
  selftests: kvm: check dynamic bits against KVM_X86_XCOMP_GUEST_SUPP
  KVM: x86: add system attribute to retrieve full set of supported xsave states
  KVM: x86: Add a helper to retrieve userspace address from kvm_device_attr
  selftests: kvm: move vm_xsave_req_perm call to amx_test
  KVM: x86: Sync the states size with the XCR0/IA32_XSS at, any time
  KVM: x86: Update vCPU's runtime CPUID on write to MSR_IA32_XSS
  KVM: x86: Keep MSR_IA32_XSS unchanged for INIT
  KVM: x86: Free kvm_cpuid_entry2 array on post-KVM_RUN KVM_SET_CPUID{,2}
  KVM: nVMX: WARN on any attempt to allocate shadow VMCS for vmcs02
  KVM: selftests: Don't skip L2's VMCALL in SMM test for SVM guest
  KVM: x86: Check .flags in kvm_cpuid_check_equal() too
  KVM: x86: Forcibly leave nested virt when SMM state is toggled
  KVM: SVM: drop unnecessary code in svm_hv_vmcb_dirty_nested_enlightenments()
  KVM: SVM: hyper-v: Enable Enlightened MSR-Bitmap support for real
  ...
2022-01-28 19:00:26 +02:00
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
Linus Torvalds
636b5284d8 Generic:
- selftest compilation fix for non-x86
 
 - KVM: avoid warning on s390 in mark_page_dirty
 
 x86:
 - fix page write-protection bug and improve comments
 
 - use binary search to lookup the PMU event filter, add test
 
 - enable_pmu module parameter support for Intel CPUs
 
 - switch blocked_vcpu_on_cpu_lock to raw spinlock
 
 - cleanups of blocked vCPU logic
 
 - partially allow KVM_SET_CPUID{,2} after KVM_RUN (5.16 regression)
 
 - various small fixes
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull more kvm updates from Paolo Bonzini:
 "Generic:

   - selftest compilation fix for non-x86

   - KVM: avoid warning on s390 in mark_page_dirty

 x86:

   - fix page write-protection bug and improve comments

   - use binary search to lookup the PMU event filter, add test

   - enable_pmu module parameter support for Intel CPUs

   - switch blocked_vcpu_on_cpu_lock to raw spinlock

   - cleanups of blocked vCPU logic

   - partially allow KVM_SET_CPUID{,2} after KVM_RUN (5.16 regression)

   - various small fixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (46 commits)
  docs: kvm: fix WARNINGs from api.rst
  selftests: kvm/x86: Fix the warning in lib/x86_64/processor.c
  selftests: kvm/x86: Fix the warning in pmu_event_filter_test.c
  kvm: selftests: Do not indent with spaces
  kvm: selftests: sync uapi/linux/kvm.h with Linux header
  selftests: kvm: add amx_test to .gitignore
  KVM: SVM: Nullify vcpu_(un)blocking() hooks if AVIC is disabled
  KVM: SVM: Move svm_hardware_setup() and its helpers below svm_x86_ops
  KVM: SVM: Drop AVIC's intermediate avic_set_running() helper
  KVM: VMX: Don't do full kick when handling posted interrupt wakeup
  KVM: VMX: Fold fallback path into triggering posted IRQ helper
  KVM: VMX: Pass desired vector instead of bool for triggering posted IRQ
  KVM: VMX: Don't do full kick when triggering posted interrupt "fails"
  KVM: SVM: Skip AVIC and IRTE updates when loading blocking vCPU
  KVM: SVM: Use kvm_vcpu_is_blocking() in AVIC load to handle preemption
  KVM: SVM: Remove unnecessary APICv/AVIC update in vCPU unblocking path
  KVM: SVM: Don't bother checking for "running" AVIC when kicking for IPIs
  KVM: SVM: Signal AVIC doorbell iff vCPU is in guest mode
  KVM: x86: Remove defunct pre_block/post_block kvm_x86_ops hooks
  KVM: x86: Unexport LAPIC's switch_to_{hv,sw}_timer() helpers
  ...
2022-01-22 09:40:01 +02:00
Wei Wang
e2e83a73d7 docs: kvm: fix WARNINGs from api.rst
Use the api number 134 for KVM_GET_XSAVE2, instead of 42, which has been
used by KVM_GET_XSAVE.
Also, fix the WARNINGs of the underlines being too short.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Message-Id: <20220120045003.315177-1-wei.w.wang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-20 12:13:35 -05:00
Linus Torvalds
79e06c4c49 RISCV:
- Use common KVM implementation of MMU memory caches
 
 - SBI v0.2 support for Guest
 
 - Initial KVM selftests support
 
 - Fix to avoid spurious virtual interrupts after clearing hideleg CSR
 
 - Update email address for Anup and Atish
 
 ARM:
 - Simplification of the 'vcpu first run' by integrating it into
   KVM's 'pid change' flow
 
 - Refactoring of the FP and SVE state tracking, also leading to
   a simpler state and less shared data between EL1 and EL2 in
   the nVHE case
 
 - Tidy up the header file usage for the nvhe hyp object
 
 - New HYP unsharing mechanism, finally allowing pages to be
   unmapped from the Stage-1 EL2 page-tables
 
 - Various pKVM cleanups around refcounting and sharing
 
 - A couple of vgic fixes for bugs that would trigger once
   the vcpu xarray rework is merged, but not sooner
 
 - Add minimal support for ARMv8.7's PMU extension
 
 - Rework kvm_pgtable initialisation ahead of the NV work
 
 - New selftest for IRQ injection
 
 - Teach selftests about the lack of default IPA space and
   page sizes
 
 - Expand sysreg selftest to deal with Pointer Authentication
 
 - The usual bunch of cleanups and doc update
 
 s390:
 - fix sigp sense/start/stop/inconsistency
 
 - cleanups
 
 x86:
 - Clean up some function prototypes more
 
 - improved gfn_to_pfn_cache with proper invalidation, used by Xen emulation
 
 - add KVM_IRQ_ROUTING_XEN_EVTCHN and event channel delivery
 
 - completely remove potential TOC/TOU races in nested SVM consistency checks
 
 - update some PMCs on emulated instructions
 
 - Intel AMX support (joint work between Thomas and Intel)
 
 - large MMU cleanups
 
 - module parameter to disable PMU virtualization
 
 - cleanup register cache
 
 - first part of halt handling cleanups
 
 - Hyper-V enlightened MSR bitmap support for nested hypervisors
 
 Generic:
 - clean up Makefiles
 
 - introduce CONFIG_HAVE_KVM_DIRTY_RING
 
 - optimize memslot lookup using a tree
 
 - optimize vCPU array usage by converting to xarray
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "RISCV:

   - Use common KVM implementation of MMU memory caches

   - SBI v0.2 support for Guest

   - Initial KVM selftests support

   - Fix to avoid spurious virtual interrupts after clearing hideleg CSR

   - Update email address for Anup and Atish

  ARM:

   - Simplification of the 'vcpu first run' by integrating it into KVM's
     'pid change' flow

   - Refactoring of the FP and SVE state tracking, also leading to a
     simpler state and less shared data between EL1 and EL2 in the nVHE
     case

   - Tidy up the header file usage for the nvhe hyp object

   - New HYP unsharing mechanism, finally allowing pages to be unmapped
     from the Stage-1 EL2 page-tables

   - Various pKVM cleanups around refcounting and sharing

   - A couple of vgic fixes for bugs that would trigger once the vcpu
     xarray rework is merged, but not sooner

   - Add minimal support for ARMv8.7's PMU extension

   - Rework kvm_pgtable initialisation ahead of the NV work

   - New selftest for IRQ injection

   - Teach selftests about the lack of default IPA space and page sizes

   - Expand sysreg selftest to deal with Pointer Authentication

   - The usual bunch of cleanups and doc update

  s390:

   - fix sigp sense/start/stop/inconsistency

   - cleanups

  x86:

   - Clean up some function prototypes more

   - improved gfn_to_pfn_cache with proper invalidation, used by Xen
     emulation

   - add KVM_IRQ_ROUTING_XEN_EVTCHN and event channel delivery

   - completely remove potential TOC/TOU races in nested SVM consistency
     checks

   - update some PMCs on emulated instructions

   - Intel AMX support (joint work between Thomas and Intel)

   - large MMU cleanups

   - module parameter to disable PMU virtualization

   - cleanup register cache

   - first part of halt handling cleanups

   - Hyper-V enlightened MSR bitmap support for nested hypervisors

  Generic:

   - clean up Makefiles

   - introduce CONFIG_HAVE_KVM_DIRTY_RING

   - optimize memslot lookup using a tree

   - optimize vCPU array usage by converting to xarray"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (268 commits)
  x86/fpu: Fix inline prefix warnings
  selftest: kvm: Add amx selftest
  selftest: kvm: Move struct kvm_x86_state to header
  selftest: kvm: Reorder vcpu_load_state steps for AMX
  kvm: x86: Disable interception for IA32_XFD on demand
  x86/fpu: Provide fpu_sync_guest_vmexit_xfd_state()
  kvm: selftests: Add support for KVM_CAP_XSAVE2
  kvm: x86: Add support for getting/setting expanded xstate buffer
  x86/fpu: Add uabi_size to guest_fpu
  kvm: x86: Add CPUID support for Intel AMX
  kvm: x86: Add XCR0 support for Intel AMX
  kvm: x86: Disable RDMSR interception of IA32_XFD_ERR
  kvm: x86: Emulate IA32_XFD_ERR for guest
  kvm: x86: Intercept #NM for saving IA32_XFD_ERR
  x86/fpu: Prepare xfd_err in struct fpu_guest
  kvm: x86: Add emulation for IA32_XFD
  x86/fpu: Provide fpu_update_guest_xfd() for IA32_XFD emulation
  kvm: x86: Enable dynamic xfeatures at KVM_SET_CPUID2
  x86/fpu: Provide fpu_enable_guest_xfd_features() for KVM
  x86/fpu: Add guest support to xfd_enable_feature()
  ...
2022-01-16 16:15:14 +02:00
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
Jing Liu
445ecdf79b kvm: x86: Exclude unpermitted xfeatures at KVM_GET_SUPPORTED_CPUID
KVM_GET_SUPPORTED_CPUID should not include any dynamic xstates in
CPUID[0xD] if they have not been requested with prctl. Otherwise
a process which directly passes KVM_GET_SUPPORTED_CPUID to
KVM_SET_CPUID2 would now fail even if it doesn't intend to use a
dynamically enabled feature. Userspace must know that prctl is
required and allocate >4K xstate buffer before setting any dynamic
bit.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jing Liu <jing2.liu@intel.com>
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Message-Id: <20220105123532.12586-5-yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-07 13:33:04 -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
David Woodhouse
1cfc9c4b9d KVM: x86/xen: Maintain valid mapping of Xen shared_info page
Use the newly reinstated gfn_to_pfn_cache to maintain a kernel mapping
of the Xen shared_info page so that it can be accessed in atomic context.

Note that we do not participate in dirty tracking for the shared info
page and we do not explicitly mark it dirty every single tim we deliver
an event channel interrupts. We wouldn't want to do that even if we *did*
have a valid vCPU context with which to do so.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20211210163625.2886-4-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-07 10:44:45 -05:00
Paolo Bonzini
5e4e84f112 KVM: s390: Fix and cleanup
- fix sigp sense/start/stop/inconsistency
 - cleanups
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Merge tag 'kvm-s390-next-5.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

KVM: s390: Fix and cleanup

- fix sigp sense/start/stop/inconsistency
- cleanups
2021-12-21 12:59:53 -05:00