Oliver Upton [Mon, 30 Oct 2023 20:21:19 +0000 (20:21 +0000)]
Merge branch kvm-arm64/mops into kvmarm/next
* kvm-arm64/mops:
: KVM support for MOPS, courtesy of Kristina Martsenko
:
: MOPS adds new instructions for accelerating memcpy(), memset(), and
: memmove() operations in hardware. This series brings virtualization
: support for KVM guests, and allows VMs to run on asymmetrict systems
: that may have different MOPS implementations.
KVM: arm64: Expose MOPS instructions to guests
KVM: arm64: Add handler for MOPS exceptions
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Oliver Upton [Mon, 30 Oct 2023 20:21:09 +0000 (20:21 +0000)]
Merge branch kvm-arm64/writable-id-regs into kvmarm/next
* kvm-arm64/writable-id-regs:
: Writable ID registers, courtesy of Jing Zhang
:
: This series significantly expands the architectural feature set that
: userspace can manipulate via the ID registers. A new ioctl is defined
: that makes the mutable fields in the ID registers discoverable to
: userspace.
KVM: selftests: Avoid using forced target for generating arm64 headers
tools headers arm64: Fix references to top srcdir in Makefile
KVM: arm64: selftests: Test for setting ID register from usersapce
tools headers arm64: Update sysreg.h with kernel sources
KVM: selftests: Generate sysreg-defs.h and add to include path
perf build: Generate arm64's sysreg-defs.h and add to include path
tools: arm64: Add a Makefile for generating sysreg-defs.h
KVM: arm64: Document vCPU feature selection UAPIs
KVM: arm64: Allow userspace to change ID_AA64ZFR0_EL1
KVM: arm64: Allow userspace to change ID_AA64PFR0_EL1
KVM: arm64: Allow userspace to change ID_AA64MMFR{0-2}_EL1
KVM: arm64: Allow userspace to change ID_AA64ISAR{0-2}_EL1
KVM: arm64: Bump up the default KVM sanitised debug version to v8p8
KVM: arm64: Reject attempts to set invalid debug arch version
KVM: arm64: Advertise selected DebugVer in DBGDIDR.Version
KVM: arm64: Use guest ID register values for the sake of emulation
KVM: arm64: Document KVM_ARM_GET_REG_WRITABLE_MASKS
KVM: arm64: Allow userspace to get the writable masks for feature ID registers
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Oliver Upton [Fri, 27 Oct 2023 00:54:39 +0000 (00:54 +0000)]
KVM: selftests: Avoid using forced target for generating arm64 headers
The 'prepare' target that generates the arm64 sysreg headers had no
prerequisites, so it wound up forcing a rebuild of all KVM selftests
each invocation. Add a rule for the generated headers and just have
dependents use that for a prerequisite.
Reported-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com> Fixes: 9697d84cc3b6 ("KVM: selftests: Generate sysreg-defs.h and add to include path") Tested-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com> Link: https://lore.kernel.org/r/20231027005439.3142015-3-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Oliver Upton [Fri, 27 Oct 2023 00:54:38 +0000 (00:54 +0000)]
tools headers arm64: Fix references to top srcdir in Makefile
Aishwarya reports that KVM selftests for arm64 fail with the following
error:
| make[4]: Entering directory '/tmp/kci/linux/tools/testing/selftests/kvm'
| Makefile:270: warning: overriding recipe for target
| '/tmp/kci/linux/build/kselftest/kvm/get-reg-list'
| Makefile:265: warning: ignoring old recipe for target
| '/tmp/kci/linux/build/kselftest/kvm/get-reg-list'
| make -C ../../../../tools/arch/arm64/tools/
| make[5]: Entering directory '/tmp/kci/linux/tools/arch/arm64/tools'
| Makefile:10: ../tools/scripts/Makefile.include: No such file or directory
| make[5]: *** No rule to make target '../tools/scripts/Makefile.include'.
| Stop.
It would appear that this only affects builds from the top-level
Makefile (e.g. make kselftest-all), as $(srctree) is set to ".". Work
around the issue by shadowing the kselftest naming scheme for the source
tree variable.
Oliver Upton [Mon, 30 Oct 2023 20:19:13 +0000 (20:19 +0000)]
Merge branch kvm-arm64/sgi-injection into kvmarm/next
* kvm-arm64/sgi-injection:
: vSGI injection improvements + fixes, courtesy Marc Zyngier
:
: Avoid linearly searching for vSGI targets using a compressed MPIDR to
: index a cache. While at it, fix some egregious bugs in KVM's mishandling
: of vcpuid (user-controlled value) and vcpu_idx.
KVM: arm64: Clarify the ordering requirements for vcpu/RD creation
KVM: arm64: vgic-v3: Optimize affinity-based SGI injection
KVM: arm64: Fast-track kvm_mpidr_to_vcpu() when mpidr_data is available
KVM: arm64: Build MPIDR to vcpu index cache at runtime
KVM: arm64: Simplify kvm_vcpu_get_mpidr_aff()
KVM: arm64: Use vcpu_idx for invalidation tracking
KVM: arm64: vgic: Use vcpu_idx for the debug information
KVM: arm64: vgic-v2: Use cpuid from userspace as vcpu_id
KVM: arm64: vgic-v3: Refactor GICv3 SGI generation
KVM: arm64: vgic-its: Treat the collection target address as a vcpu_id
KVM: arm64: vgic: Make kvm_vgic_inject_irq() take a vcpu pointer
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Oliver Upton [Mon, 30 Oct 2023 20:18:56 +0000 (20:18 +0000)]
Merge branch kvm-arm64/stage2-vhe-load into kvmarm/next
* kvm-arm64/stage2-vhe-load:
: Setup stage-2 MMU from vcpu_load() for VHE
:
: Unlike nVHE, there is no need to switch the stage-2 MMU around on guest
: entry/exit in VHE mode as the host is running at EL2. Despite this KVM
: reloads the stage-2 on every guest entry, which is needless.
:
: This series moves the setup of the stage-2 MMU context to vcpu_load()
: when running in VHE mode. This is likely to be a win across the board,
: but also allows us to remove an ISB on the guest entry path for systems
: with one of the speculative AT errata.
KVM: arm64: Move VTCR_EL2 into struct s2_mmu
KVM: arm64: Load the stage-2 MMU context in kvm_vcpu_load_vhe()
KVM: arm64: Rename helpers for VHE vCPU load/put
KVM: arm64: Reload stage-2 for VMID change on VHE
KVM: arm64: Restore the stage-2 context in VHE's __tlb_switch_to_host()
KVM: arm64: Don't zero VTTBR in __tlb_switch_to_host()
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Oliver Upton [Mon, 30 Oct 2023 20:18:46 +0000 (20:18 +0000)]
Merge branch kvm-arm64/nv-trap-fixes into kvmarm/next
* kvm-arm64/nv-trap-fixes:
: NV trap forwarding fixes, courtesy Miguel Luis and Marc Zyngier
:
: - Explicitly define the effects of HCR_EL2.NV on EL2 sysregs in the
: NV trap encoding
:
: - Make EL2 registers that access AArch32 guest state UNDEF or RAZ/WI
: where appropriate for NV guests
KVM: arm64: Handle AArch32 SPSR_{irq,abt,und,fiq} as RAZ/WI
KVM: arm64: Do not let a L1 hypervisor access the *32_EL2 sysregs
KVM: arm64: Refine _EL2 system register list that require trap reinjection
arm64: Add missing _EL2 encodings
arm64: Add missing _EL12 encodings
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Oliver Upton [Mon, 30 Oct 2023 20:18:37 +0000 (20:18 +0000)]
Merge branch kvm-arm64/smccc-filter-cleanups into kvmarm/next
* kvm-arm64/smccc-filter-cleanups:
: Cleanup the management of KVM's SMCCC maple tree
:
: Avoid the cost of maintaining the SMCCC filter maple tree if userspace
: hasn't writen a rule to the filter. While at it, rip out the now
: unnecessary VM flag to indicate whether or not the SMCCC filter was
: configured.
KVM: arm64: Use mtree_empty() to determine if SMCCC filter configured
KVM: arm64: Only insert reserved ranges when SMCCC filter is used
KVM: arm64: Add a predicate for testing if SMCCC filter is configured
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Oliver Upton [Mon, 30 Oct 2023 20:18:23 +0000 (20:18 +0000)]
Merge branch kvm-arm64/pmevtyper-filter into kvmarm/next
* kvm-arm64/pmevtyper-filter:
: Fixes to KVM's handling of the PMUv3 exception level filtering bits
:
: - NSH (count at EL2) and M (count at EL3) should be stateful when the
: respective EL is advertised in the ID registers but have no effect on
: event counting.
:
: - NSU and NSK modify the event filtering of EL0 and EL1, respectively.
: Though the kernel may not use these bits, other KVM guests might.
: Implement these bits exactly as written in the pseudocode if EL3 is
: advertised.
KVM: arm64: Add PMU event filter bits required if EL3 is implemented
KVM: arm64: Make PMEVTYPER<n>_EL0.NSH RES0 if EL2 isn't advertised
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Oliver Upton [Mon, 30 Oct 2023 20:18:14 +0000 (20:18 +0000)]
Merge branch kvm-arm64/feature-flag-refactor into kvmarm/next
* kvm-arm64/feature-flag-refactor:
: vCPU feature flag cleanup
:
: Clean up KVM's handling of vCPU feature flags to get rid of the
: vCPU-scoped bitmaps and remove failure paths from kvm_reset_vcpu().
KVM: arm64: Get rid of vCPU-scoped feature bitmap
KVM: arm64: Remove unused return value from kvm_reset_vcpu()
KVM: arm64: Hoist NV+SVE check into KVM_ARM_VCPU_INIT ioctl handler
KVM: arm64: Prevent NV feature flag on systems w/o nested virt
KVM: arm64: Hoist PAuth checks into KVM_ARM_VCPU_INIT ioctl
KVM: arm64: Hoist SVE check into KVM_ARM_VCPU_INIT ioctl handler
KVM: arm64: Hoist PMUv3 check into KVM_ARM_VCPU_INIT ioctl handler
KVM: arm64: Add generic check for system-supported vCPU features
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Oliver Upton [Mon, 30 Oct 2023 20:18:00 +0000 (20:18 +0000)]
Merge branch kvm-arm64/misc into kvmarm/next
* kvm-arm64/misc:
: Miscellaneous updates
:
: - Put an upper bound on the number of I-cache invalidations by
: cacheline to avoid soft lockups
:
: - Get rid of bogus refererence count transfer for THP mappings
:
: - Do a local TLB invalidation on permission fault race
:
: - Fixes for page_fault_test KVM selftest
:
: - Add a tracepoint for detecting MMIO instructions unsupported by KVM
KVM: arm64: Add tracepoint for MMIO accesses where ISV==0
KVM: arm64: selftest: Perform ISB before reading PAR_EL1
KVM: arm64: selftest: Add the missing .guest_prepare()
KVM: arm64: Always invalidate TLB for stage-2 permission faults
KVM: arm64: Do not transfer page refcount for THP adjustment
KVM: arm64: Avoid soft lockups due to I-cache maintenance
arm64: tlbflush: Rename MAX_TLBI_OPS
KVM: arm64: Don't use kerneldoc comment for arm64_check_features()
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Oliver Upton [Thu, 26 Oct 2023 20:53:06 +0000 (20:53 +0000)]
KVM: arm64: Add tracepoint for MMIO accesses where ISV==0
It is a pretty well known fact that KVM does not support MMIO emulation
without valid instruction syndrome information (ESR_EL2.ISV == 0). The
current kvm_pr_unimpl() is pretty useless, as it contains zero context
to relate the event to a vCPU.
Replace it with a precise tracepoint that dumps the relevant context
so the user can make sense of what the guest is doing.
Zenghui Yu [Sat, 7 Oct 2023 12:40:43 +0000 (20:40 +0800)]
KVM: arm64: selftest: Perform ISB before reading PAR_EL1
It looks like a mistake to issue ISB *after* reading PAR_EL1, we should
instead perform it between the AT instruction and the reads of PAR_EL1.
As according to DDI0487J.a IJTYVP,
"When an address translation instruction is executed, explicit
synchronization is required to guarantee the result is visible to
subsequent direct reads of PAR_EL1."
Otherwise all guest_at testcases fail on my box with
==== Test Assertion Failure ====
aarch64/page_fault_test.c:142: par & 1 == 0
pid=1355864 tid=1355864 errno=4 - Interrupted system call
1 0x0000000000402853: vcpu_run_loop at page_fault_test.c:681
2 0x0000000000402cdb: run_test at page_fault_test.c:730
3 0x0000000000403897: for_each_guest_mode at guest_modes.c:100
4 0x00000000004019f3: for_each_test_and_guest_mode at page_fault_test.c:1105
5 (inlined by) main at page_fault_test.c:1131
6 0x0000ffffb153c03b: ?? ??:0
7 0x0000ffffb153c113: ?? ??:0
8 0x0000000000401aaf: _start at ??:?
0x1 != 0x0 (par & 1 != 0)
Zenghui Yu [Sat, 7 Oct 2023 12:40:42 +0000 (20:40 +0800)]
KVM: arm64: selftest: Add the missing .guest_prepare()
Running page_fault_test on a Cortex A72 fails with
Test: ro_memslot_no_syndrome_guest_cas
Testing guest mode: PA-bits:40, VA-bits:48, 4K pages
Testing memory backing src type: anonymous
==== Test Assertion Failure ====
aarch64/page_fault_test.c:117: guest_check_lse()
pid=1944087 tid=1944087 errno=4 - Interrupted system call
1 0x00000000004028b3: vcpu_run_loop at page_fault_test.c:682
2 0x0000000000402d93: run_test at page_fault_test.c:731
3 0x0000000000403957: for_each_guest_mode at guest_modes.c:100
4 0x00000000004019f3: for_each_test_and_guest_mode at page_fault_test.c:1108
5 (inlined by) main at page_fault_test.c:1134
6 0x0000ffff868e503b: ?? ??:0
7 0x0000ffff868e5113: ?? ??:0
8 0x0000000000401aaf: _start at ??:?
guest_check_lse()
because we don't have a guest_prepare stage to check the presence of
FEAT_LSE and skip the related guest_cas testing, and we end-up failing in
GUEST_ASSERT(guest_check_lse()).
Add the missing .guest_prepare() where it's indeed required.
Oliver Upton [Fri, 22 Sep 2023 22:32:29 +0000 (22:32 +0000)]
KVM: arm64: Always invalidate TLB for stage-2 permission faults
It is possible for multiple vCPUs to fault on the same IPA and attempt
to resolve the fault. One of the page table walks will actually update
the PTE and the rest will return -EAGAIN per our race detection scheme.
KVM elides the TLB invalidation on the racing threads as the return
value is nonzero.
Before commit a12ab1378a88 ("KVM: arm64: Use local TLBI on permission
relaxation") KVM always used broadcast TLB invalidations when handling
permission faults, which had the convenient property of making the
stage-2 updates visible to all CPUs in the system. However now we do a
local invalidation, and TLBI elision leads to the vCPU thread faulting
again on the stale entry. Remember that the architecture permits the TLB
to cache translations that precipitate a permission fault.
Invalidate the TLB entry responsible for the permission fault if the
stage-2 descriptor has been relaxed, regardless of which thread actually
did the job.
Marc Zyngier [Mon, 23 Oct 2023 09:54:44 +0000 (10:54 +0100)]
KVM: arm64: Handle AArch32 SPSR_{irq,abt,und,fiq} as RAZ/WI
When trapping accesses from a NV guest that tries to access
SPSR_{irq,abt,und,fiq}, make sure we handle them as RAZ/WI,
as if AArch32 wasn't implemented.
This involves a bit of repainting to make the visibility
handler more generic.
Marc Zyngier [Mon, 23 Oct 2023 09:54:43 +0000 (10:54 +0100)]
KVM: arm64: Do not let a L1 hypervisor access the *32_EL2 sysregs
DBGVCR32_EL2, DACR32_EL2, IFSR32_EL2 and FPEXC32_EL2 are required to
UNDEF when AArch32 isn't implemented, which is definitely the case when
running NV.
Given that this is the only case where these registers can trap,
unconditionally inject an UNDEF exception.
Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Reviewed-by: Eric Auger <eric.auger@redhat.com> Link: https://lore.kernel.org/r/20231023095444.1587322-5-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Miguel Luis [Mon, 23 Oct 2023 09:54:42 +0000 (10:54 +0100)]
KVM: arm64: Refine _EL2 system register list that require trap reinjection
Implement a fine grained approach in the _EL2 sysreg range instead of
the current wide cast trap. This ensures that we don't mistakenly
inject the wrong exception into the guest.
[maz: commit message massaging, dropped secure and AArch32 registers
from the list]
Fixes: d0fc0a2519a6 ("KVM: arm64: nv: Add trap forwarding for HCR_EL2") Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Miguel Luis <miguel.luis@oracle.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20231023095444.1587322-4-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Miguel Luis [Mon, 23 Oct 2023 09:54:41 +0000 (10:54 +0100)]
arm64: Add missing _EL2 encodings
Some _EL2 encodings are missing. Add them.
Signed-off-by: Miguel Luis <miguel.luis@oracle.com> Reviewed-by: Eric Auger <eric.auger@redhat.com>
[maz: dropped secure encodings] Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20231023095444.1587322-3-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Miguel Luis [Mon, 23 Oct 2023 09:54:40 +0000 (10:54 +0100)]
arm64: Add missing _EL12 encodings
Some _EL12 encodings are missing. Add them.
Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Miguel Luis <miguel.luis@oracle.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20231023095444.1587322-2-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Oliver Upton [Thu, 19 Oct 2023 18:56:18 +0000 (18:56 +0000)]
KVM: arm64: Add PMU event filter bits required if EL3 is implemented
Suzuki noticed that KVM's PMU emulation is oblivious to the NSU and NSK
event filter bits. On systems that have EL3 these bits modify the
filter behavior in non-secure EL0 and EL1, respectively. Even though the
kernel doesn't use these bits, it is entirely possible some other guest
OS does. Additionally, it would appear that these and the M bit are
required by the architecture if EL3 is implemented.
Allow the EL3 event filter bits to be set if EL3 is advertised in the
guest's ID register. Implement the behavior of NSU and NSK according to
the pseudocode, and entirely ignore the M bit for perf event creation.
Oliver Upton [Thu, 19 Oct 2023 18:56:17 +0000 (18:56 +0000)]
KVM: arm64: Make PMEVTYPER<n>_EL0.NSH RES0 if EL2 isn't advertised
The NSH bit, which filters event counting at EL2, is required by the
architecture if an implementation has EL2. Even though KVM doesn't
support nested virt yet, it makes no effort to hide the existence of EL2
from the ID registers. Userspace can, however, change the value of PFR0
to hide EL2. Align KVM's sysreg emulation with the architecture and make
NSH RES0 if EL2 isn't advertised. Keep in mind the bit is ignored when
constructing the backing perf event.
While at it, build the event type mask using explicit field definitions
instead of relying on ARMV8_PMU_EVTYPE_MASK. KVM probably should've been
doing this in the first place, as it avoids changes to the
aforementioned mask affecting sysreg emulation.
Marc Zyngier [Thu, 12 Oct 2023 20:51:08 +0000 (21:51 +0100)]
KVM: arm64: Move VTCR_EL2 into struct s2_mmu
We currently have a global VTCR_EL2 value for each guest, even
if the guest uses NV. This implies that the guest's own S2 must
fit in the host's. This is odd, for multiple reasons:
- the PARange values and the number of IPA bits don't necessarily
match: you can have 33 bits of IPA space, and yet you can only
describe 32 or 36 bits of PARange
- When userspace set the IPA space, it creates a contract with the
kernel saying "this is the IPA space I'm prepared to handle".
At no point does it constraint the guest's own IPA space as
long as the guest doesn't try to use a [I]PA outside of the
IPA space set by userspace
- We don't even try to hide the value of ID_AA64MMFR0_EL1.PARange.
And then there is the consequence of the above: if a guest tries
to create a S2 that has for input address something that is larger
than the IPA space defined by the host, we inject a fatal exception.
This is no good. For all intent and purposes, a guest should be
able to have the S2 it really wants, as long as the *output* address
of that S2 isn't outside of the IPA space.
For that, we need to have a per-s2_mmu VTCR_EL2 setting, which
allows us to represent the full PARange. Move the vctr field into
the s2_mmu structure, which has no impact whatsoever, except for NV.
Note that once we are able to override ID_AA64MMFR0_EL1.PARange
from userspace, we'll also be able to restrict the size of the
shadow S2 that NV uses.
Oliver Upton [Wed, 18 Oct 2023 23:32:12 +0000 (23:32 +0000)]
KVM: arm64: Load the stage-2 MMU context in kvm_vcpu_load_vhe()
To date the VHE code has aggressively reloaded the stage-2 MMU context
on every guest entry, despite the fact that this isn't necessary. This
was probably done for consistency with the nVHE code, which needs to
switch in/out the stage-2 MMU context as both the host and guest run at
EL1.
Hoist __load_stage2() into kvm_vcpu_load_vhe(), thus avoiding a reload
on every guest entry/exit. This is likely to be beneficial to systems
with one of the speculative AT errata, as there is now one fewer context
synchronization event on the guest entry path. Additionally, it is
possible that implementations have hitched correctness mitigations on
writes to VTTBR_EL2, which are now elided on guest re-entry.
Note that __tlb_switch_to_guest() is deliberately left untouched as it
can be called outside the context of a running vCPU.
Oliver Upton [Wed, 18 Oct 2023 23:32:11 +0000 (23:32 +0000)]
KVM: arm64: Rename helpers for VHE vCPU load/put
The names for the helpers we expose to the 'generic' KVM code are a bit
imprecise; we switch the EL0 + EL1 sysreg context and setup trap
controls that do not need to change for every guest entry/exit. Rename +
shuffle things around a bit in preparation for loading the stage-2 MMU
context on vcpu_load().
Marc Zyngier [Wed, 18 Oct 2023 23:32:10 +0000 (23:32 +0000)]
KVM: arm64: Reload stage-2 for VMID change on VHE
Naturally, a change to the VMID for an MMU implies a new value for
VTTBR. Reload on VMID change in anticipation of loading stage-2 on
vcpu_load() instead of every guest entry.
Marc Zyngier [Wed, 18 Oct 2023 23:32:09 +0000 (23:32 +0000)]
KVM: arm64: Restore the stage-2 context in VHE's __tlb_switch_to_host()
An MMU notifier could cause us to clobber the stage-2 context loaded on
a CPU when we switch to another VM's context to invalidate. This isn't
an issue right now as the stage-2 context gets reloaded on every guest
entry, but is disastrous when moving __load_stage2() into the
vcpu_load() path.
Restore the previous stage-2 context on the way out of a TLB
invalidation if we installed something else. Deliberately do this after
TGE=1 is synchronized to keep things safe in light of the speculative AT
errata.
Jing Zhang [Wed, 11 Oct 2023 19:57:40 +0000 (19:57 +0000)]
KVM: arm64: selftests: Test for setting ID register from usersapce
Add tests to verify setting ID registers from userspace is handled
correctly by KVM. Also add a test case to use ioctl
KVM_ARM_GET_REG_WRITABLE_MASKS to get writable masks.
Jing Zhang [Wed, 11 Oct 2023 19:57:39 +0000 (19:57 +0000)]
tools headers arm64: Update sysreg.h with kernel sources
The users of sysreg.h (perf, KVM selftests) are now generating the
necessary sysreg-defs.h; sync sysreg.h with the kernel sources and
fix the KVM selftests that use macros which suffered a rename.
Oliver Upton [Wed, 11 Oct 2023 19:57:38 +0000 (19:57 +0000)]
KVM: selftests: Generate sysreg-defs.h and add to include path
Start generating sysreg-defs.h for arm64 builds in anticipation of
updating sysreg.h to a version that depends on it.
Reviewed-by: Mark Brown <broonie@kernel.org> Reviewed-by: Eric Auger <eric.auger@redhat.com> Tested-by: Eric Auger <eric.auger@redhat.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20231011195740.3349631-4-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Oliver Upton [Wed, 11 Oct 2023 19:57:36 +0000 (19:57 +0000)]
tools: arm64: Add a Makefile for generating sysreg-defs.h
Use a common Makefile for generating sysreg-defs.h, which will soon be
needed by perf and KVM selftests. The naming scheme of the generated
macros is not expected to change, so just refer to the canonical
script/data in the kernel source rather than copying to tools.
Co-developed-by: Jing Zhang <jingzhangos@google.com> Signed-off-by: Jing Zhang <jingzhangos@google.com> Reviewed-by: Mark Brown <broonie@kernel.org> Reviewed-by: Eric Auger <eric.auger@redhat.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20231011195740.3349631-2-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Expose the Armv8.8 FEAT_MOPS feature to guests in the ID register and
allow the MOPS instructions to be run in a guest. Only expose MOPS if
the whole system supports it.
Note, it is expected that guests do not use these instructions on MMIO,
similarly to other instructions where ESR_EL2.ISV==0 such as LDP/STP.
An Armv8.8 FEAT_MOPS main or epilogue instruction will take an exception
if executed on a CPU with a different MOPS implementation option (A or
B) than the CPU where the preceding prologue instruction ran. In this
case the OS exception handler is expected to reset the registers and
restart execution from the prologue instruction.
A KVM guest may use the instructions at EL1 at times when the guest is
not able to handle the exception, expecting that the instructions will
only run on one CPU (e.g. when running UEFI boot services in the guest).
As KVM may reschedule the guest between different types of CPUs at any
time (on an asymmetric system), it needs to also handle the resulting
exception itself in case the guest is not able to. A similar situation
will also occur in the future when live migrating a guest from one type
of CPU to another.
Add handling for the MOPS exception to KVM. The handling can be shared
with the EL0 exception handler, as the logic and register layouts are
the same. The exception can be handled right after exiting a guest,
which avoids the cost of returning to the host exit handler.
Similarly to the EL0 exception handler, in case the main or epilogue
instruction is being single stepped, it makes sense to finish the step
before executing the prologue instruction, so advance the single step
state machine.
Oliver Upton [Wed, 4 Oct 2023 23:49:47 +0000 (23:49 +0000)]
KVM: arm64: Use mtree_empty() to determine if SMCCC filter configured
The smccc_filter maple tree is only populated if userspace attempted to
configure it. Use the state of the maple tree to determine if the filter
has been configured, eliminating the VM flag.
Oliver Upton [Wed, 4 Oct 2023 23:49:46 +0000 (23:49 +0000)]
KVM: arm64: Only insert reserved ranges when SMCCC filter is used
The reserved ranges are only useful for preventing userspace from
adding a rule that intersects with functions we must handle in KVM. If
userspace never writes to the SMCCC filter than this is all just wasted
work/memory.
Insert reserved ranges on the first call to KVM_ARM_VM_SMCCC_FILTER.
Oliver Upton [Tue, 3 Oct 2023 23:04:06 +0000 (23:04 +0000)]
KVM: arm64: Document vCPU feature selection UAPIs
KVM/arm64 has a couple schemes for handling vCPU feature selection now,
which is a lot to put on userspace. Add some documentation about how
these interact and provide some recommendations for how to use the
writable ID register scheme.
Oliver Upton [Tue, 3 Oct 2023 23:04:05 +0000 (23:04 +0000)]
KVM: arm64: Allow userspace to change ID_AA64ZFR0_EL1
All known fields in ID_AA64ZFR0_EL1 describe the unprivileged
instructions supported by the PE's SVE implementation. Allow userspace
to pick and choose the advertised feature set, though nothing stops the
guest from using undisclosed instructions.
Jing Zhang [Tue, 3 Oct 2023 23:04:03 +0000 (23:04 +0000)]
KVM: arm64: Allow userspace to change ID_AA64MMFR{0-2}_EL1
Allow userspace to modify the guest-visible values of these ID
registers. Prevent changes to any of the virtualization features until
KVM picks up support for nested and we have a handle on managing NV
features.
Oliver Upton [Tue, 3 Oct 2023 23:04:02 +0000 (23:04 +0000)]
KVM: arm64: Allow userspace to change ID_AA64ISAR{0-2}_EL1
Almost all of the features described by the ISA registers have no KVM
involvement. Allow userspace to change the value of these registers with
a couple exceptions:
- MOPS is not writable as KVM does not currently virtualize FEAT_MOPS.
- The PAuth fields are not writable as KVM requires both address and
generic authentication be enabled.
Oliver Upton [Tue, 3 Oct 2023 23:04:00 +0000 (23:04 +0000)]
KVM: arm64: Reject attempts to set invalid debug arch version
The debug architecture is mandatory in ARMv8, so KVM should not allow
userspace to configure a vCPU with less than that. Of course, this isn't
handled elegantly by the generic ID register plumbing, as the respective
ID register fields have a nonzero starting value.
Add an explicit check for debug versions less than v8 of the
architecture.
Oliver Upton [Wed, 4 Oct 2023 17:03:17 +0000 (17:03 +0000)]
KVM: arm64: Advertise selected DebugVer in DBGDIDR.Version
Much like we do for other fields, extract the Debug architecture version
from the ID register to populate the corresponding field in DBGDIDR.
Rewrite the existing sysreg field extractors to use SYS_FIELD_GET() for
consistency.
Suggested-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Jing Zhang [Tue, 3 Oct 2023 23:03:57 +0000 (23:03 +0000)]
KVM: arm64: Allow userspace to get the writable masks for feature ID registers
While the Feature ID range is well defined and pretty large, it isn't
inconceivable that the architecture will eventually grow some other
ranges that will need to similarly be described to userspace.
Add a VM ioctl to allow userspace to get writable masks for feature ID
registers in below system register space:
op0 = 3, op1 = {0, 1, 3}, CRn = 0, CRm = {0 - 7}, op2 = {0 - 7}
This is used to support mix-and-match userspace and kernels for writable
ID registers, where userspace may want to know upfront whether it can
actually tweak the contents of an idreg or not.
Add a new capability (KVM_CAP_ARM_SUPPORTED_FEATURE_ID_RANGES) that
returns a bitmap of the valid ranges, which can subsequently be
retrieved, one at a time by setting the index of the set bit as the
range identifier.
Suggested-by: Marc Zyngier <maz@kernel.org> Suggested-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Jing Zhang <jingzhangos@google.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20231003230408.3405722-2-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Marc Zyngier [Wed, 27 Sep 2023 09:09:11 +0000 (10:09 +0100)]
KVM: arm64: Clarify the ordering requirements for vcpu/RD creation
It goes without saying, but it is probably better to spell it out:
If userspace tries to restore and VM, but creates vcpus and/or RDs
in a different order, the vcpu/RD mapping will be different. Yes,
our API is an ugly piece of crap and I can't believe that we missed
this.
If we want to relax the above, we'll need to define a new userspace
API that allows the mapping to be specified, rather than relying
on the kernel to perform the mapping on its own.
Our affinity-based SGI injection code is a bit daft. We iterate
over all the CPUs trying to match the set of affinities that the
guest is trying to reach, leading to some very bad behaviours
if the selected targets are at a high vcpu index.
Instead, we can now use the fact that we have an optimised
MPIDR to vcpu mapping, and only look at the relevant values.
This results in a much faster injection for large VMs, and
in a near constant time, irrespective of the position in the
vcpu index space.
As a bonus, this is mostly deleting a lot of hard-to-read
code. Nobody will complain about that.
Marc Zyngier [Wed, 27 Sep 2023 09:09:08 +0000 (10:09 +0100)]
KVM: arm64: Build MPIDR to vcpu index cache at runtime
The MPIDR_EL1 register contains a unique value that identifies
the CPU. The only problem with it is that it is stupidly large
(32 bits, once the useless stuff is removed).
Trying to obtain a vcpu from an MPIDR value is a fairly common,
yet costly operation: we iterate over all the vcpus until we
find the correct one. While this is cheap for small VMs, it is
pretty expensive on large ones, specially if you are trying to
get to the one that's at the end of the list...
In order to help with this, it is important to realise that
the MPIDR values are actually structured, and that implementations
tend to use a small number of significant bits in the 32bit space.
We can use this fact to our advantage by computing a small hash
table that uses the "compression" of the significant MPIDR bits
as an index, giving us the vcpu index as a result.
Given that the MPIDR values can be supplied by userspace, and
that an evil VMM could decide to make *all* bits significant,
resulting in a 4G-entry table, we only use this method if the
resulting table fits in a single page. Otherwise, we fallback
to the good old iterative method.
Nothing uses that table just yet, but keep your eyes peeled.
Marc Zyngier [Wed, 27 Sep 2023 09:09:06 +0000 (10:09 +0100)]
KVM: arm64: Use vcpu_idx for invalidation tracking
While vcpu_id isn't necessarily a bad choice as an identifier for
the currently running vcpu, it is provided by userspace, and there
is close to no guarantee that it would be unique.
Switch it to vcpu_idx instead, for which we have much stronger
guarantees.
Marc Zyngier [Wed, 27 Sep 2023 09:09:04 +0000 (10:09 +0100)]
KVM: arm64: vgic-v2: Use cpuid from userspace as vcpu_id
When parsing a GICv2 attribute that contains a cpuid, handle this
as the vcpu_id, not a vcpu_idx, as userspace cannot really know
the mapping between the two. For this, use kvm_get_vcpu_by_id()
instead of kvm_get_vcpu().
Take this opportunity to get rid of the pointless check against
online_vcpus, which doesn't make much sense either, and switch
to FIELD_GET as a way to extract the vcpu_id.
As we're about to change the way SGIs are sent, start by splitting
out some of the basic functionnality: instead of intermingling
the broadcast and non-broadcast cases with the actual SGI generation,
perform the following cleanups:
- move the SGI queuing into its own helper
- split the broadcast code from the affinity-driven code
- replace the mask/shift combinations with FIELD_GET()
- fix the confusion between vcpu_id and vcpu when handling
the broadcast case
The result is much more readable, and paves the way for further
optimisations.
Marc Zyngier [Wed, 27 Sep 2023 09:09:02 +0000 (10:09 +0100)]
KVM: arm64: vgic-its: Treat the collection target address as a vcpu_id
Since our emulated ITS advertises GITS_TYPER.PTA=0, the target
address associated to a collection is a PE number and not
an address. So far, so good. However, the PE number is what userspace
has provided given us (aka the vcpu_id), and not the internal vcpu
index.
Make sure we consistently retrieve the vcpu by ID rather than
by index, adding a helper that deals with most of the cases.
We also get rid of the pointless (and bogus) comparisons to
online_vcpus, which don't really make sense.
KVM: arm64: Do not transfer page refcount for THP adjustment
GUP affects a refcount common to all pages forming the THP. There is
therefore no need to move the refcount from a tail to the head page.
Under the hood it decrements and increments the same counter.
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
"ARM:
- Fix EL2 Stage-1 MMIO mappings where a random address was used
- Fix SMCCC function number comparison when the SVE hint is set
RISC-V:
- Fix KVM_GET_REG_LIST API for ISA_EXT registers
- Fix reading ISA_EXT register of a missing extension
- Fix ISA_EXT register handling in get-reg-list test
- Fix filtering of AIA registers in get-reg-list test
x86:
- Fixes for TSC_AUX virtualization
- Stop zapping page tables asynchronously, since we don't zap them as
often as before"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: SVM: Do not use user return MSR support for virtualized TSC_AUX
KVM: SVM: Fix TSC_AUX virtualization setup
KVM: SVM: INTERCEPT_RDTSCP is never intercepted anyway
KVM: x86/mmu: Stop zapping invalidated TDP MMU roots asynchronously
KVM: x86/mmu: Do not filter address spaces in for_each_tdp_mmu_root_yield_safe()
KVM: x86/mmu: Open code leaf invalidation from mmu_notifier
KVM: riscv: selftests: Selectively filter-out AIA registers
KVM: riscv: selftests: Fix ISA_EXT register handling in get-reg-list
RISC-V: KVM: Fix riscv_vcpu_get_isa_ext_single() for missing extensions
RISC-V: KVM: Fix KVM_GET_REG_LIST API for ISA_EXT registers
KVM: selftests: Assert that vasprintf() is successful
KVM: arm64: nvhe: Ignore SVE hint in SMCCC function ID
KVM: arm64: Properly return allocated EL2 VA from hyp_alloc_private_va_range()
Merge tag 'trace-v6.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing fixes from Steven Rostedt:
- Fix the "bytes" output of the per_cpu stat file
The tracefs/per_cpu/cpu*/stats "bytes" was giving bogus values as the
accounting was not accurate. It is suppose to show how many used
bytes are still in the ring buffer, but even when the ring buffer was
empty it would still show there were bytes used.
- Fix a bug in eventfs where reading a dynamic event directory (open)
and then creating a dynamic event that goes into that diretory screws
up the accounting.
On close, the newly created event dentry will get a "dput" without
ever having a "dget" done for it. The fix is to allocate an array on
dir open to save what dentries were actually "dget" on, and what ones
to "dput" on close.
* tag 'trace-v6.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
eventfs: Remember what dentries were created on dir open
ring-buffer: Fix bytes info in per_cpu buffer stats
Merge tag 'cxl-fixes-6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl
Pull cxl fixes from Dan Williams:
"A collection of regression fixes, bug fixes, and some small cleanups
to the Compute Express Link code.
The regressions arrived in the v6.5 dev cycle and missed the v6.6
merge window due to my personal absences this cycle. The most
important fixes are for scenarios where the CXL subsystem fails to
parse valid region configurations established by platform firmware.
This is important because agreement between OS and BIOS on the CXL
configuration is fundamental to implementing "OS native" error
handling, i.e. address translation and component failure
identification.
Other important fixes are a driver load error when the BIOS lets the
Linux PCI core handle AER events, but not CXL memory errors.
The other fixex might have end user impact, but for now are only known
to trigger in our test/emulation environment.
Summary:
- Fix multiple scenarios where platform firmware defined regions fail
to be assembled by the CXL core.
- Fix a spurious driver-load failure on platforms that enable OS
native AER, but not OS native CXL error handling.
- Fix a regression detecting "poison" commands when "security"
commands are also defined.
- Fix a cxl_test regression with the move to centralize CXL port
register enumeration in the CXL core.
- Miscellaneous small fixes and cleanups"
* tag 'cxl-fixes-6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl:
cxl/acpi: Annotate struct cxl_cxims_data with __counted_by
cxl/port: Fix cxl_test register enumeration regression
cxl/region: Refactor granularity select in cxl_port_setup_targets()
cxl/region: Match auto-discovered region decoders by HPA range
cxl/mbox: Fix CEL logic for poison and security commands
cxl/pci: Replace host_bridge->native_aer with pcie_aer_is_native()
PCI/AER: Export pcie_aer_is_native()
cxl/pci: Fix appropriate checking for _OSC while handling CXL RAS registers
Merge tag 'gpio-fixes-for-v6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux
Pull gpio fixes from Bartosz Golaszewski:
- fix an invalid usage of __free(kfree) leading to kfreeing an
ERR_PTR()
- fix an irq domain leak in gpio-tb10x
- MAINTAINERS update
* tag 'gpio-fixes-for-v6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
gpio: sim: fix an invalid __free() usage
gpio: tb10x: Fix an error handling path in tb10x_gpio_probe()
MAINTAINERS: gpio-regmap: make myself a maintainer of it
Merge tag 'mm-hotfixes-stable-2023-09-23-10-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
"13 hotfixes, 10 of which pertain to post-6.5 issues. The other three
are cc:stable"
* tag 'mm-hotfixes-stable-2023-09-23-10-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
proc: nommu: fix empty /proc/<pid>/maps
filemap: add filemap_map_order0_folio() to handle order0 folio
proc: nommu: /proc/<pid>/maps: release mmap read lock
mm: memcontrol: fix GFP_NOFS recursion in memory.high enforcement
pidfd: prevent a kernel-doc warning
argv_split: fix kernel-doc warnings
scatterlist: add missing function params to kernel-doc
selftests/proc: fixup proc-empty-vm test after KSM changes
revert "scripts/gdb/symbols: add specific ko module load command"
selftests: link libasan statically for tests with -fsanitize=address
task_work: add kerneldoc annotation for 'data' argument
mm: page_alloc: fix CMA and HIGHATOMIC landing on the wrong buddy list
sh: mm: re-add lost __ref to ioremap_prot() to fix modpost warning
Merge tag 'i2c-for-6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c fixes from Wolfram Sang:
"A set of I2C driver fixes. Mostly fixing resource leaks or sanity
checks"
* tag 'i2c-for-6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: xiic: Correct return value check for xiic_reinit()
i2c: mux: gpio: Add missing fwnode_handle_put()
i2c: mux: demux-pinctrl: check the return value of devm_kstrdup()
i2c: designware: fix __i2c_dw_disable() in case master is holding SCL low
i2c: i801: unregister tco_pdev in i801_probe() error path
Charles Keepax [Tue, 19 Sep 2023 11:03:20 +0000 (13:03 +0200)]
mfd: cs42l43: Use correct macro for new-style PM runtime ops
The code was accidentally mixing new and old style macros, update the
macros used to remove an unused function warning whilst building with
no PM enabled in the config.
Fixes: ace6d1448138 ("mfd: cs42l43: Add support for cs42l43 core driver") Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com> Link: https://lore.kernel.org/all/20230822114914.340359-1-ckeepax@opensource.cirrus.com/ Reviewed-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Lee Jones <lee@kernel.org> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge tag 'loongarch-fixes-6.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
Pull LoongArch fixes from Huacai Chen:
"Fix lockdep, fix a boot failure, fix some build warnings, fix document
links, and some cleanups"
* tag 'loongarch-fixes-6.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
docs/zh_CN/LoongArch: Update the links of ABI
docs/LoongArch: Update the links of ABI
LoongArch: Don't inline kasan_mem_to_shadow()/kasan_shadow_to_mem()
kasan: Cleanup the __HAVE_ARCH_SHADOW_MAP usage
LoongArch: Set all reserved memblocks on Node#0 at initialization
LoongArch: Remove dead code in relocate_new_kernel
LoongArch: Use _UL() and _ULL()
LoongArch: Fix some build warnings with W=1
LoongArch: Fix lockdep static memory detection
Merge tag 'iomap-6.6-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull iomap fixes from Darrick Wong:
- Return EIO on bad inputs to iomap_to_bh instead of BUGging, to deal
less poorly with block device io racing with block device resizing
- Fix a stale page data exposure bug introduced in 6.6-rc1 when
unsharing a file range that is not in the page cache
* tag 'iomap-6.6-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
iomap: convert iomap_unshare_iter to use large folios
iomap: don't skip reading in !uptodate folios when unsharing a range
iomap: handle error conditions more gracefully in iomap_to_bh
Paolo Bonzini [Sat, 23 Sep 2023 09:35:55 +0000 (05:35 -0400)]
Merge tag 'kvm-riscv-fixes-6.6-1' of https://github.com/kvm-riscv/linux into HEAD
KVM/riscv fixes for 6.6, take #1
- Fix KVM_GET_REG_LIST API for ISA_EXT registers
- Fix reading ISA_EXT register of a missing extension
- Fix ISA_EXT register handling in get-reg-list test
- Fix filtering of AIA registers in get-reg-list test
Tom Lendacky [Fri, 15 Sep 2023 20:54:32 +0000 (15:54 -0500)]
KVM: SVM: Do not use user return MSR support for virtualized TSC_AUX
When the TSC_AUX MSR is virtualized, the TSC_AUX value is swap type "B"
within the VMSA. This means that the guest value is loaded on VMRUN and
the host value is restored from the host save area on #VMEXIT.
Since the value is restored on #VMEXIT, the KVM user return MSR support
for TSC_AUX can be replaced by populating the host save area with the
current host value of TSC_AUX. And, since TSC_AUX is not changed by Linux
post-boot, the host save area can be set once in svm_hardware_enable().
This eliminates the two WRMSR instructions associated with the user return
MSR support.
Tom Lendacky [Fri, 15 Sep 2023 20:54:30 +0000 (15:54 -0500)]
KVM: SVM: Fix TSC_AUX virtualization setup
The checks for virtualizing TSC_AUX occur during the vCPU reset processing
path. However, at the time of initial vCPU reset processing, when the vCPU
is first created, not all of the guest CPUID information has been set. In
this case the RDTSCP and RDPID feature support for the guest is not in
place and so TSC_AUX virtualization is not established.
This continues for each vCPU created for the guest. On the first boot of
an AP, vCPU reset processing is executed as a result of an APIC INIT
event, this time with all of the guest CPUID information set, resulting
in TSC_AUX virtualization being enabled, but only for the APs. The BSP
always sees a TSC_AUX value of 0 which probably went unnoticed because,
at least for Linux, the BSP TSC_AUX value is 0.
Move the TSC_AUX virtualization enablement out of the init_vmcb() path and
into the vcpu_after_set_cpuid() path to allow for proper initialization of
the support after the guest CPUID information has been set.
With the TSC_AUX virtualization support now in the vcpu_set_after_cpuid()
path, the intercepts must be either cleared or set based on the guest
CPUID input.
Fixes: 296d5a17e793 ("KVM: SEV-ES: Use V_TSC_AUX if available instead of RDTSC/MSR_TSC_AUX intercepts") Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <4137fbcb9008951ab5f0befa74a0399d2cce809a.1694811272.git.thomas.lendacky@amd.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Fri, 22 Sep 2023 21:06:34 +0000 (17:06 -0400)]
KVM: SVM: INTERCEPT_RDTSCP is never intercepted anyway
svm_recalc_instruction_intercepts() is always called at least once
before the vCPU is started, so the setting or clearing of the RDTSCP
intercept can be dropped from the TSC_AUX virtualization support.
Extracted from a patch by Tom Lendacky.
Cc: stable@vger.kernel.org Fixes: 296d5a17e793 ("KVM: SEV-ES: Use V_TSC_AUX if available instead of RDTSC/MSR_TSC_AUX intercepts") Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Stop zapping invalidate TDP MMU roots via work queue now that KVM
preserves TDP MMU roots until they are explicitly invalidated. Zapping
roots asynchronously was effectively a workaround to avoid stalling a vCPU
for an extended during if a vCPU unloaded a root, which at the time
happened whenever the guest toggled CR0.WP (a frequent operation for some
guest kernels).
While a clever hack, zapping roots via an unbound worker had subtle,
unintended consequences on host scheduling, especially when zapping
multiple roots, e.g. as part of a memslot. Because the work of zapping a
root is no longer bound to the task that initiated the zap, things like
the CPU affinity and priority of the original task get lost. Losing the
affinity and priority can be especially problematic if unbound workqueues
aren't affined to a small number of CPUs, as zapping multiple roots can
cause KVM to heavily utilize the majority of CPUs in the system, *beyond*
the CPUs KVM is already using to run vCPUs.
When deleting a memslot via KVM_SET_USER_MEMORY_REGION, the async root
zap can result in KVM occupying all logical CPUs for ~8ms, and result in
high priority tasks not being scheduled in in a timely manner. In v5.15,
which doesn't preserve unloaded roots, the issues were even more noticeable
as KVM would zap roots more frequently and could occupy all CPUs for 50ms+.
Consuming all CPUs for an extended duration can lead to significant jitter
throughout the system, e.g. on ChromeOS with virtio-gpu, deleting memslots
is a semi-frequent operation as memslots are deleted and recreated with
different host virtual addresses to react to host GPU drivers allocating
and freeing GPU blobs. On ChromeOS, the jitter manifests as audio blips
during games due to the audio server's tasks not getting scheduled in
promptly, despite the tasks having a high realtime priority.
Deleting memslots isn't exactly a fast path and should be avoided when
possible, and ChromeOS is working towards utilizing MAP_FIXED to avoid the
memslot shenanigans, but KVM is squarely in the wrong. Not to mention
that removing the async zapping eliminates a non-trivial amount of
complexity.
Note, one of the subtle behaviors hidden behind the async zapping is that
KVM would zap invalidated roots only once (ignoring partial zaps from
things like mmu_notifier events). Preserve this behavior by adding a flag
to identify roots that are scheduled to be zapped versus roots that have
already been zapped but not yet freed.
Add a comment calling out why kvm_tdp_mmu_invalidate_all_roots() can
encounter invalid roots, as it's not at all obvious why zapping
invalidated roots shouldn't simply zap all invalid roots.
Reported-by: Pattara Teerapong <pteerapong@google.com> Cc: David Stevens <stevensd@google.com> Cc: Yiwei Zhang<zzyiwei@google.com> Cc: Paul Hsia <paulhsia@google.com> Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230916003916.2545000-4-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Thu, 21 Sep 2023 09:44:56 +0000 (05:44 -0400)]
KVM: x86/mmu: Do not filter address spaces in for_each_tdp_mmu_root_yield_safe()
All callers except the MMU notifier want to process all address spaces.
Remove the address space ID argument of for_each_tdp_mmu_root_yield_safe()
and switch the MMU notifier to use __for_each_tdp_mmu_root_yield_safe().
Extracted out of a patch by Sean Christopherson <seanjc@google.com>
Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* tag 'hardening-v6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
uapi: stddef.h: Fix __DECLARE_FLEX_ARRAY for C++
uapi: stddef.h: Fix header guard location
Merge tag 'xfs-6.6-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fixes from Chandan Babu:
- Fix an integer overflow bug when processing an fsmap call
- Fix crash due to CPU hot remove event racing with filesystem mount
operation
- During read-only mount, XFS does not allow the contents of the log to
be recovered when there are one or more unrecognized rcompat features
in the primary superblock, since the log might have intent items
which the kernel does not know how to process
- During recovery of log intent items, XFS now reserves log space
sufficient for one cycle of a permanent transaction to execute.
Otherwise, this could lead to livelocks due to non-availability of
log space
- On an fs which has an ondisk unlinked inode list, trying to delete a
file or allocating an O_TMPFILE file can cause the fs to the shutdown
if the first inode in the ondisk inode list is not present in the
inode cache. The bug is solved by explicitly loading the first inode
in the ondisk unlinked inode list into the inode cache if it is not
already cached
A similar problem arises when the uncached inode is present in the
middle of the ondisk unlinked inode list. This second bug is
triggered when executing operations like quotacheck and bulkstat. In
this case, XFS now reads in the entire ondisk unlinked inode list
- Enable LARP mode only on recent v5 filesystems
- Fix a out of bounds memory access in scrub
- Fix a performance bug when locating the tail of the log during
mounting a filesystem
* tag 'xfs-6.6-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: use roundup_pow_of_two instead of ffs during xlog_find_tail
xfs: only call xchk_stats_merge after validating scrub inputs
xfs: require a relatively recent V5 filesystem for LARP mode
xfs: make inode unlinked bucket recovery work with quotacheck
xfs: load uncached unlinked inodes into memory on demand
xfs: reserve less log space when recovering log intent items
xfs: fix log recovery when unknown rocompat bits are set
xfs: reload entire unlinked bucket lists
xfs: allow inode inactivation during a ro mount log recovery
xfs: use i_prev_unlinked to distinguish inodes that are not on the unlinked list
xfs: remove CPU hotplug infrastructure
xfs: remove the all-mounts list
xfs: use per-mount cpumask to track nonempty percpu inodegc lists
xfs: fix an agbno overflow in __xfs_getfsmap_datadev
xfs: fix per-cpu CIL structure aggregation racing with dying cpus
xfs: fix select in config XFS_ONLINE_SCRUB_STATS
cxl/acpi: Annotate struct cxl_cxims_data with __counted_by
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct cxl_cxims_data.
Additionally, since the element count member must be set before accessing
the annotated flexible array member, move its initialization earlier.
The cxl_test unit test environment models a CXL topology for
sysfs/user-ABI regression testing. It uses interface mocking via the
"--wrap=" linker option to redirect cxl_core routines that parse
hardware registers with versions that just publish objects, like
devm_cxl_enumerate_decoders().
Starting with:
Commit 19ab69a60e3b ("cxl/port: Store the port's Component Register mappings in struct cxl_port")
...port register enumeration is moved into devm_cxl_add_port(). This
conflicts with the "cxl_test avoids emulating registers stance" so
either the port code needs to be refactored (too violent), or modified
so that register enumeration is skipped on "fake" cxl_test ports
(annoying, but straightforward).
This conflict has happened previously and the "check for platform
device" workaround to avoid instrusive refactoring was deployed in those
scenarios. In general, refactoring should only benefit production code,
test code needs to remain minimally instrusive to the greatest extent
possible.
This was missed previously because it may sometimes just cause warning
messages to be emitted, but it can also cause test failures. The
backport to -stable is only nice to have for clean cxl_test runs.
Fixes: 19ab69a60e3b ("cxl/port: Store the port's Component Register mappings in struct cxl_port") Cc: stable@vger.kernel.org Reported-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Tested-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/169476525052.1013896.6235102957693675187.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
eventfs: Remember what dentries were created on dir open
Using the following code with libtracefs:
int dfd;
// create the directory events/kprobes/kp1
tracefs_kprobe_raw(NULL, "kp1", "schedule_timeout", "time=$arg1");
// Open the kprobes directory
dfd = tracefs_instance_file_open(NULL, "events/kprobes", O_RDONLY);
// Do a lookup of the kprobes/kp1 directory (by looking at enable)
tracefs_file_exists(NULL, "events/kprobes/kp1/enable");
// Now create a new entry in the kprobes directory
tracefs_kprobe_raw(NULL, "kp2", "schedule_hrtimeout", "expires=$arg1");
// Do another lookup to create the dentries
tracefs_file_exists(NULL, "events/kprobes/kp2/enable"))
// Close the directory
close(dfd);
What happened above, the first open (dfd) will call
dcache_dir_open_wrapper() that will create the dentries and up their ref
counts.
Now the creation of "kp2" will add another dentry within the kprobes
directory.
Upon the close of dfd, eventfs_release() will now do a dput for all the
entries in kprobes. But this is where the problem lies. The open only
upped the dentry of kp1 and not kp2. Now the close is decrementing both
kp1 and kp2, which causes kp2 to get a negative count.
Doing a "trace-cmd reset" which deletes all the kprobes cause the kernel
to crash! (due to the messed up accounting of the ref counts).
To solve this, save all the dentries that are opened in the
dcache_dir_open_wrapper() into an array, and use this array to know what
dentries to do a dput on in eventfs_release().
Since the dcache_dir_open_wrapper() calls dcache_dir_open() which uses the
file->private_data, we need to also add a wrapper around dcache_readdir()
that uses the cursor assigned to the file->private_data. This is because
the dentries need to also be saved in the file->private_data. To do this
create the structure:
Which will hold both the cursor and the dentries. Some shuffling around is
needed to make sure that dcache_dir_open() and dcache_readdir() only see
the cursor.
ring-buffer: Fix bytes info in per_cpu buffer stats
The 'bytes' info in file 'per_cpu/cpu<X>/stats' means the number of
bytes in cpu buffer that have not been consumed. However, currently
after consuming data by reading file 'trace_pipe', the 'bytes' info
was not changed as expected.
The root cause is incorrect stat on cpu_buffer->read_bytes. To fix it:
1. When stat 'read_bytes', account consumed event in rb_advance_reader();
2. When stat 'entries_bytes', exclude the discarded padding event which
is smaller than minimum size because it is invisible to reader. Then
use rb_page_commit() instead of BUF_PAGE_SIZE at where accounting for
page-based read/remove/overrun.
Also correct the comments of ring_buffer_bytes_cpu() in this patch.
Merge tag 'thermal-6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull thermal control fix from Rafael Wysocki:
"Unbreak the trip point update sysfs interface that has been broken
since the 6.3 cycle (Rafael Wysocki)"
* tag 'thermal-6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
thermal: sysfs: Fix trip_point_hyst_store()
Merge tag 'acpi-6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI fixes from Rafael Wysocki:
"These fix a general ACPI processor driver regression and an ia64 build
issue, both introduced recently.
Specifics:
- Fix recently introduced uninitialized memory access issue in the
ACPI processor driver (Michal Wilczynski)
- Fix ia64 build inadvertently broken by recent ACPI processor driver
changes, which is prudent to do for 6.6 even though ia64 support is
slated for removal in 6.7 (Ard Biesheuvel)"
* tag 'acpi-6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: processor: Fix uninitialized access of buf in acpi_set_pdc_bits()
acpi: Provide ia64 dummy implementation of acpi_proc_quirk_mwait_check()
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
"Small crop of relatively boring arm64 fixes for -rc3.
That's not to say we don't have any juicy bugs, however, it's just
that fixes for those are likely to come via -mm and -tip for a hugetlb
and an atomics issue respectively. I get left with the
documentation...
- Fix detection of "ClearBHB" and "Hinted Conditional Branch" features
- Fix broken wildcarding for Arm PMU MAINTAINERS entry
- Add missing documentation for userspace-visible ID register fields"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: Document missing userspace visible fields in ID_AA64ISAR2_EL1
arm64/hbc: Document HWCAP2_HBC
arm64/sme: Include ID_AA64PFR1_EL1.SME in cpu-feature-registers.rst
arm64: cpufeature: Fix CLRBHB and BC detection
MAINTAINERS: Use wildcard pattern for ARM PMU headers
Merge tag 'x86_urgent_for_v6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 rethunk fixes from Borislav Petkov:
"Fix the patching ordering between static calls and return thunks"
* tag 'x86_urgent_for_v6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86,static_call: Fix static-call vs return-thunk
x86/alternatives: Remove faulty optimization
Merge tag 'x86-urgent-2023-09-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull misc x86 fixes from Ingo Molnar:
- Fix a kexec bug
- Fix an UML build bug
- Fix a handful of SRSO related bugs
- Fix a shadow stacks handling bug & robustify related code
* tag 'x86-urgent-2023-09-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/shstk: Add warning for shadow stack double unmap
x86/shstk: Remove useless clone error handling
x86/shstk: Handle vfork clone failure correctly
x86/srso: Fix SBPB enablement for spec_rstack_overflow=off
x86/srso: Don't probe microcode in a guest
x86/srso: Set CPUID feature bits independently of bug or mitigation status
x86/srso: Fix srso_show_state() side effect
x86/asm: Fix build of UML with KASAN
x86/mm, kexec, ima: Use memblock_free_late() from ima_free_kexec_buffer()
Merge tag 'locking-urgent-2023-09-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Ingo Molnar:
"Fix a include/linux/atomic/atomic-arch-fallback.h breakage that
generated incorrect code, and fix a lockdep reporting race that may
result in lockups"
* tag 'locking-urgent-2023-09-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/seqlock: Do the lockdep annotation before locking in do_write_seqcount_begin_nested()
locking/atomic: scripts: fix fallback ifdeffery
Oliver Upton [Wed, 20 Sep 2023 08:01:33 +0000 (08:01 +0000)]
KVM: arm64: Avoid soft lockups due to I-cache maintenance
Gavin reports of soft lockups on his Ampere Altra Max machine when
backing KVM guests with hugetlb pages. Upon further investigation, it
was found that the system is unable to keep up with parallel I-cache
invalidations done by KVM's stage-2 fault handler.
This is ultimately an implementation problem. I-cache maintenance
instructions are available at EL0, so nothing stops a malicious
userspace from hammering a system with CMOs and cause it to fall over.
"Fixing" this problem in KVM is nothing more than slapping a bandage
over a much deeper problem.
Anyway, the kernel already has a heuristic for limiting TLB
invalidations to avoid soft lockups. Reuse that logic to limit I-cache
CMOs done by KVM to map executable pages on systems without FEAT_DIC.
While at it, restructure __invalidate_icache_guest_page() to improve
readability and squeeze our new condition into the existing branching
structure.
Oliver Upton [Wed, 20 Sep 2023 08:01:32 +0000 (08:01 +0000)]
arm64: tlbflush: Rename MAX_TLBI_OPS
Perhaps unsurprisingly, I-cache invalidations suffer from performance
issues similar to TLB invalidations on certain systems. TLB and I-cache
maintenance all result in DVM on the mesh, which is where the real
bottleneck lies.
Rename the heuristic to point the finger at DVM, such that it may be
reused for limiting I-cache invalidations.
095b8303f383 ("x86/alternative: Make custom return thunk unconditional")
made '__x86_return_thunk' a placeholder value. All code setting
X86_FEATURE_RETHUNK also changes the value of 'x86_return_thunk'. So
the optimization at the beginning of apply_returns() is dead code.
Also, before the above-mentioned commit, the optimization actually had a
bug It bypassed __static_call_fixup(), causing some raw returns to
remain unpatched in static call trampolines. Thus the 'Fixes' tag.
Merge tag 'efi-fixes-for-v6.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi
Pull EFI fix from Ard Biesheuvel:
"Follow-up fix for the unaccepted memory fix merged last week as part
of the first EFI fixes batch.
The unaccepted memory table needs to be accessible very early, even in
cases (such as crashkernels) where the direct map does not cover all
of DRAM, and so it is added to memblock explicitly, and subsequently
memblock_reserve()'d as before"
* tag 'efi-fixes-for-v6.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
efi/unaccepted: Make sure unaccepted table is mapped
Merge tag 'drm-fixes-2023-09-22-2' of git://anongit.freedesktop.org/drm/drm
Pull drm fixes from Dave Airlie:
"Ben Skeggs is stepping away from nouveau and Red Hat for personal
reasons, he'll be missed and we intend to fill the gaps in the
upcoming time with Danilo and Lyude stepping in for now.
Otherwise i915, nouveau, amdgpu with a few each and some misc spread
around.
MAINTAINERS:
- drop Ben as he retired from nouveau
core:
- drm_mm test fixes
fbdev:
- Kconfig fixes
ivpu:
- IRQ-handling fixes
meson:
- Fix memory leak in HDMI EDID code
nouveau:
- Correct type casting
- Fix memory leak in scheduler
- u_memcpya() fixes
i915:
- Prevent error pointer dereference
- Fix PMU busyness values when using GuC mode
amdgpu:
- MST fix
- Vbios part number reporting fix
- Fix a possible memory leak in an error case in the RAS code
- Fix low resolution modes on eDP
amdkfd:
- Fix GPU address for user queue wptr when GART is not at 0"
* tag 'drm-fixes-2023-09-22-2' of git://anongit.freedesktop.org/drm/drm:
MAINTAINERS: remove myself as nouveau maintainer
fbdev/sh7760fb: Depend on FB=y
drm/amdkfd: Use gpu_offset for user queue's wptr
drm/amd/display: fix the ability to use lower resolution modes on eDP
drm/amdgpu: fix a memory leak in amdgpu_ras_feature_enable
Revert "drm/amdgpu: Report vbios version instead of PN"
drm/amd/display: Fix MST recognizes connected displays as one
drm/virtio: clean out_fence on complete_submit
i915/pmu: Move execlist stats initialization to execlist specific setup
drm/i915/gt: Prevent error pointer dereference
drm/meson: fix memory leak on ->hpd_notify callback
accel/ivpu/40xx: Fix buttress interrupt handling
nouveau/u_memcpya: fix NULL vs error pointer bug
nouveau/u_memcpya: use vmemdup_user
drm/nouveau: sched: fix leaking memory of timedout job
drm/nouveau: fence: fix type cast warning in nouveau_fence_emit()
drm: fix up fbdev Kconfig defaults
drm/tests: Fix incorrect argument in drm_test_mm_insert_range