KVM/arm64 updates for 6.19
- Support for userspace handling of synchronous external aborts (SEAs),
allowing the VMM to potentially handle the abort in a non-fatal
manner.
- Large rework of the VGIC's list register handling with the goal of
supporting more active/pending IRQs than available list registers in
hardware. In addition, the VGIC now supports EOImode==1 style
deactivations for IRQs which may occur on a separate vCPU than the
one that acked the IRQ.
- Support for FEAT_XNX (user / privileged execute permissions) and
FEAT_HAF (hardware update to the Access Flag) in the software page
table walkers and shadow MMU.
- Allow page table destruction to reschedule, fixing long need_resched
latencies observed when destroying a large VM.
- Minor fixes to KVM and selftests
LoongArch KVM changes for v6.19
1. Get VM PMU capability from HW GCFG register.
2. Add AVEC basic support.
3. Use 64-bit register definition for EIOINTC.
4. Add KVM timer test cases for tools/selftests.
* kvm-arm64/nv-xnx-haf: (22 commits)
: Support for FEAT_XNX and FEAT_HAF in nested
:
: Add support for a couple of MMU-related features that weren't
: implemented by KVM's software page table walk:
:
: - FEAT_XNX: Allows the hypervisor to describe execute permissions
: separately for EL0 and EL1
:
: - FEAT_HAF: Hardware update of the Access Flag, which in the context of
: nested means software walkers must also set the Access Flag.
:
: The series also adds some basic support for testing KVM's emulation of
: the AT instruction, including the implementation detail that AT sets the
: Access Flag in KVM.
KVM: arm64: at: Update AF on software walk only if VM has FEAT_HAFDBS
KVM: arm64: at: Use correct HA bit in TCR_EL2 when regime is EL2
KVM: arm64: Document KVM_PGTABLE_PROT_{UX,PX}
KVM: arm64: Fix spelling mistake "Unexpeced" -> "Unexpected"
KVM: arm64: Add break to default case in kvm_pgtable_stage2_pte_prot()
KVM: arm64: Add endian casting to kvm_swap_s[12]_desc()
KVM: arm64: Fix compilation when CONFIG_ARM64_USE_LSE_ATOMICS=n
KVM: arm64: selftests: Add test for AT emulation
KVM: arm64: nv: Expose hardware access flag management to NV guests
KVM: arm64: nv: Implement HW access flag management in stage-2 SW PTW
KVM: arm64: Implement HW access flag management in stage-1 SW PTW
KVM: arm64: Propagate PTW errors up to AT emulation
KVM: arm64: Add helper for swapping guest descriptor
KVM: arm64: nv: Use pgtable definitions in stage-2 walk
KVM: arm64: Handle endianness in read helper for emulated PTW
KVM: arm64: nv: Stop passing vCPU through void ptr in S2 PTW
KVM: arm64: Call helper for reading descriptors directly
KVM: arm64: nv: Advertise support for FEAT_XNX
KVM: arm64: Teach ptdump about FEAT_XNX permissions
KVM: arm64: nv: Forward FEAT_XNX permissions to the shadow stage-2
...
Signed-off-by: Oliver Upton <oupton@kernel.org>
* kvm-arm64/vgic-lr-overflow: (50 commits)
: Support for VGIC LR overflows, courtesy of Marc Zyngier
:
: Address deficiencies in KVM's GIC emulation when a vCPU has more active
: IRQs than can be represented in the VGIC list registers. Sort the AP
: list to prioritize inactive and pending IRQs, potentially spilling
: active IRQs outside of the LRs.
:
: Handle deactivation of IRQs outside of the LRs for both EOImode=0/1,
: which involves special consideration for SPIs being deactivated from a
: different vCPU than the one that acked it.
KVM: arm64: Convert ICH_HCR_EL2_TDIR cap to EARLY_LOCAL_CPU_FEATURE
KVM: arm64: selftests: vgic_irq: Add timer deactivation test
KVM: arm64: selftests: vgic_irq: Add Group-0 enable test
KVM: arm64: selftests: vgic_irq: Add asymmetric SPI deaectivation test
KVM: arm64: selftests: vgic_irq: Perform EOImode==1 deactivation in ack order
KVM: arm64: selftests: vgic_irq: Remove LR-bound limitation
KVM: arm64: selftests: vgic_irq: Exclude timer-controlled interrupts
KVM: arm64: selftests: vgic_irq: Change configuration before enabling interrupt
KVM: arm64: selftests: vgic_irq: Fix GUEST_ASSERT_IAR_EMPTY() helper
KVM: arm64: selftests: gic_v3: Disable Group-0 interrupts by default
KVM: arm64: selftests: gic_v3: Add irq group setting helper
KVM: arm64: GICv2: Always trap GICV_DIR register
KVM: arm64: GICv2: Handle deactivation via GICV_DIR traps
KVM: arm64: GICv2: Handle LR overflow when EOImode==0
KVM: arm64: GICv3: Force exit to sync ICH_HCR_EL2.En
KVM: arm64: GICv3: nv: Plug L1 LR sync into deactivation primitive
KVM: arm64: GICv3: nv: Resync LRs/VMCR/HCR early for better MI emulation
KVM: arm64: GICv3: Avoid broadcast kick on CPUs lacking TDIR
KVM: arm64: GICv3: Handle in-LR deactivation when possible
KVM: arm64: GICv3: Add SPI tracking to handle asymmetric deactivation
...
Signed-off-by: Oliver Upton <oupton@kernel.org>
Add timer test case based on common arch_timer code, timer interrupt
with one-shot and period mode is tested.
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Add some basic function interfaces such as CSR register access, local
irq enable or disable APIs.
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
When system returns from exception with ertn instruction, PC comes from
LOONGARCH_CSR_ERA, and CSR.CRMD comes LOONGARCH_CSR_PRMD.
Here save CSR register CSR.ERA and CSR.PRMD into stack, and then restore
them from stack. So it can be modified by exception handlers in future.
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
KVM selftests changes for 6.19:
- Fix a math goof in mmu_stress_test when running on a single-CPU system/VM.
- Forcefully override ARCH from x86_64 to x86 to play nice with specifying
ARCH=x86_64 on the command line.
- Extend a bunch of nested VMX to validate nested SVM as well.
- Add support for LA57 in the core VM_MODE_xxx macro, and add a test to
verify KVM can save/restore nested VMX state when L1 is using 5-level
paging, but L2 is not.
- Clean up the guest paging code in anticipation of sharing the core logic for
nested EPT and nested NPT.
Call paths leading to __virt_pg_map() are currently:
(a) virt_pg_map() -> virt_arch_pg_map() -> __virt_pg_map()
(b) virt_map_level() -> __virt_pg_map()
For (a), calls to virt_pg_map() from kvm_util.c make sure they update
vm->vpages_mapped, but other callers do not. Move the sparsebit_set()
call into virt_pg_map() to make sure all callers are captured.
For (b), call sparsebit_set_num() from virt_map_level().
It's tempting to have a single the call inside __virt_pg_map(), however:
- The call path in (a) is not x86-specific, while (b) is. Moving the
call into __virt_pg_map() would require doing something similar for
other archs implementing virt_pg_map().
- Future changes will reusue __virt_pg_map() for nested PTEs, which should
not update vm->vpages_mapped, i.e. a triple underscore version that does
not update vm->vpages_mapped would need to be provided.
Signed-off-by: Yosry Ahmed <yosry.ahmed@linux.dev>
Link: https://patch.msgid.link/20251021074736.1324328-12-yosry.ahmed@linux.dev
Signed-off-by: Sean Christopherson <seanjc@google.com>
vgic_lpi_stress sends MAPTI and MAPC commands during guest GIC setup to
map interrupt events to ITT entries and collection IDs to
redistributors, respectively.
We have no guarantee that the ITS will finish handling these mapping
commands before the selftest calls KVM_SIGNAL_MSI to inject LPIs to the
guest. If LPIs are injected before ITS mapping completes, the ITS cannot
properly pass the interrupt on to the redistributor.
Fix by adding a SYNC command to the selftests ITS library, then calling
SYNC after ITS mapping to ensure mapping completes before signal_lpi()
writes to GITS_TRANSLATER.
Signed-off-by: Maximilian Dittgen <mdittgen@amazon.de>
Link: https://msgid.link/20251119135744.68552-2-mdittgen@amazon.de
Signed-off-by: Oliver Upton <oupton@kernel.org>
Rename "guest_paddr" variables in vm_userspace_mem_region_add() and
vm_mem_add() to KVM's de facto standard "gpa", both for consistency and
to shorten line lengths.
Opportunistically fix the indentation of the
vm_userspace_mem_region_add() declaration.
Link: https://patch.msgid.link/20251007223625.369939-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Add NUMA helpers to probe for support/availability and to check if the
test is running on a multi-node system. The APIs will be used to verify
guest_memfd NUMA support.
Signed-off-by: Shivank Garg <shivankg@amd.com>
[sean: land helpers in numaif.h, add comments, tweak names]
Link: https://lore.kernel.org/r/20251016172853.52451-11-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Drop the KVM's re-definitions of MPOL_xxx flags in numaif.h as they are
defined by the already-included, kernel-provided mempolicy.h. The only
reason the duplicate definitions don't cause compiler warnings is because
they are identical, but only on x86-64! The syscall numbers in particular
are subtly x86_64-specific, i.e. will cause problems if/when numaif.h is
used outsize of x86.
Opportunistically clean up the file comment as the license information is
covered by the SPDX header, the path is superfluous, and as above the
comment about the contents is flat out wrong.
Fixes: 346b59f220 ("KVM: selftests: Add missing header file needed by xAPIC IPI tests")
Reviewed-by: Shivank Garg <shivankg@amd.com>
Tested-by: Shivank Garg <shivankg@amd.com>
Link: https://lore.kernel.org/r/20251016172853.52451-10-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Add APIs for all syscalls defined in the kernel's mm/mempolicy.c to match
those that would be provided by linking to libnuma. Opportunistically use
the recently inroduced KVM_SYSCALL_DEFINE() builders to take care of the
boilerplate, and to fix a flaw where the two existing wrappers would
generate multiple symbols if numaif.h were to be included multiple times.
Reviewed-by: Ackerley Tng <ackerleytng@google.com>
Tested-by: Ackerley Tng <ackerleytng@google.com>
Reviewed-by: Shivank Garg <shivankg@amd.com>
Tested-by: Shivank Garg <shivankg@amd.com>
Link: https://lore.kernel.org/r/20251016172853.52451-9-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Add kvm_<sycall> wrappers for munmap(), close(), fallocate(), and
ftruncate() to cut down on boilerplate code when a sycall is expected
to succeed, and to make it easier for developers to remember to assert
success.
Implement and use a macro framework similar to the kernel's SYSCALL_DEFINE
infrastructure to further cut down on boilerplate code, and to drastically
reduce the probability of typos as the kernel's syscall definitions can be
copy+paste almost verbatim.
Provide macros to build the raw <sycall>() wrappers as well, e.g. to
replace hand-coded wrappers (NUMA) or pure open-coded calls.
Reviewed-by: Ackerley Tng <ackerleytng@google.com>
Tested-by: Ackerley Tng <ackerleytng@google.com>
Reviewed-by: Shivank Garg <shivankg@amd.com>
Tested-by: Shivank Garg <shivankg@amd.com>
Link: https://lore.kernel.org/r/20251016172853.52451-7-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
KVM x86 fixes for 6.18:
- Expand the KVM_PRE_FAULT_MEMORY selftest to add a regression test for the
bug fixed by commit 3ccbf6f470 ("KVM: x86/mmu: Return -EAGAIN if userspace
deletes/moves memslot during prefault")
- Don't try to get PMU capabbilities from perf when running a CPU with hybrid
CPUs/PMUs, as perf will rightly WARN.
- Rework KVM_CAP_GUEST_MEMFD_MMAP (newly introduced in 6.18) into a more
generic KVM_CAP_GUEST_MEMFD_FLAGS
- Add a guest_memfd INIT_SHARED flag and require userspace to explicitly set
said flag to initialize memory as SHARED, irrespective of MMAP. The
behavior merged in 6.18 is that enabling mmap() implicitly initializes
memory as SHARED, which would result in an ABI collision for x86 CoCo VMs
as their memory is currently always initialized PRIVATE.
- Allow mmap() on guest_memfd for x86 CoCo VMs, i.e. on VMs with private
memory, to enable testing such setups, i.e. to hopefully flush out any
other lurking ABI issues before 6.18 is officially released.
- Add testcases to the guest_memfd selftest to cover guest_memfd without MMAP,
and host userspace accesses to mmap()'d private memory.
The KVM_IRQFD ioctl fails if no irqchip is present in-kernel, which
isn't too surprising as there's not much KVM can do for an IRQ if it
cannot resolve a destination.
As written the irqfd_test assumes that a 'default' VM created in
selftests has an in-kernel irqchip created implicitly. That may be the
case on x86 but it isn't necessarily true on other architectures.
Add an arch predicate indicating if 'default' VMs get an irqchip and
make the irqfd_test depend on it. Work around arm64 VGIC initialization
requirements by using vm_create_with_one_vcpu(), ignoring the created
vCPU as it isn't used for the test.
Reported-by: Sebastian Ott <sebott@redhat.com>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Acked-by: Sean Christopherson <seanjc@google.com>
Fixes: 7e9b231c40 ("KVM: selftests: Add a KVM_IRQFD test to verify uniqueness requirements")
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
A defect against the architecture now allows an implementation to treat
AMO as 1 when HCR_EL2.{E2H, TGE} = {1, 0}. KVM now takes advantage of
this interpretation to address a quality of emulation issue w.r.t.
SError injection.
Add a corresponding test case and expect a pending SError to be taken.
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Extract the guest_memfd test's SIGBUS handling functionality into a common
TEST_EXPECT_SIGBUS() macro in anticipation of adding more SIGBUS testcases.
Eating a SIGBUS isn't terrible difficult, but it requires a non-trivial
amount of boilerplate code, and using a macro allows selftests to print
out the exact action that failed to generate a SIGBUS without the developer
needing to remember to add a useful error message.
Explicitly mark the SIGBUS handler as "used", as gcc-14 at least likes to
discard the function before linking.
Opportunistically use TEST_FAIL(...) instead of TEST_ASSERT(false, ...),
and fix the write path of the guest_memfd test to use the local "val"
instead of hardcoding the literal value a second time.
Suggested-by: Ackerley Tng <ackerleytng@google.com>
Reviewed-by: Ackerley Tng <ackerleytng@google.com>
Tested-by: Ackerley Tng <ackerleytng@google.com>
Reviewed-by: Lisa Wang <wyihan@google.com>
Tested-by: Lisa Wang <wyihan@google.com>
Link: https://lore.kernel.org/r/20251003232606.4070510-12-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
KVM x86 CET virtualization support for 6.18
Add support for virtualizing Control-flow Enforcement Technology (CET) on
Intel (Shadow Stacks and Indirect Branch Tracking) and AMD (Shadow Stacks).
CET is comprised of two distinct features, Shadow Stacks (SHSTK) and Indirect
Branch Tracking (IBT), that can be utilized by software to help provide
Control-flow integrity (CFI). SHSTK defends against backward-edge attacks
(a.k.a. Return-oriented programming (ROP)), while IBT defends against
forward-edge attacks (a.k.a. similarly CALL/JMP-oriented programming (COP/JOP)).
Attackers commonly use ROP and COP/JOP methodologies to redirect the control-
flow to unauthorized targets in order to execute small snippets of code,
a.k.a. gadgets, of the attackers choice. By chaining together several gadgets,
an attacker can perform arbitrary operations and circumvent the system's
defenses.
SHSTK defends against backward-edge attacks, which execute gadgets by modifying
the stack to branch to the attacker's target via RET, by providing a second
stack that is used exclusively to track control transfer operations. The
shadow stack is separate from the data/normal stack, and can be enabled
independently in user and kernel mode.
When SHSTK is is enabled, CALL instructions push the return address on both the
data and shadow stack. RET then pops the return address from both stacks and
compares the addresses. If the return addresses from the two stacks do not
match, the CPU generates a Control Protection (#CP) exception.
IBT defends against backward-edge attacks, which branch to gadgets by executing
indirect CALL and JMP instructions with attacker controlled register or memory
state, by requiring the target of indirect branches to start with a special
marker instruction, ENDBRANCH. If an indirect branch is executed and the next
instruction is not an ENDBRANCH, the CPU generates a #CP. Note, ENDBRANCH
behaves as a NOP if IBT is disabled or unsupported.
From a virtualization perspective, CET presents several problems. While SHSTK
and IBT have two layers of enabling, a global control in the form of a CR4 bit,
and a per-feature control in user and kernel (supervisor) MSRs (U_CET and S_CET
respectively), the {S,U}_CET MSRs can be context switched via XSAVES/XRSTORS.
Practically speaking, intercepting and emulating XSAVES/XRSTORS is not a viable
option due to complexity, and outright disallowing use of XSTATE to context
switch SHSTK/IBT state would render the features unusable to most guests.
To limit the overall complexity without sacrificing performance or usability,
simply ignore the potential virtualization hole, but ensure that all paths in
KVM treat SHSTK/IBT as usable by the guest if the feature is supported in
hardware, and the guest has access to at least one of SHSTK or IBT. I.e. allow
userspace to advertise one of SHSTK or IBT if both are supported in hardware,
even though doing so would allow a misbehaving guest to use the unadvertised
feature.
Fully emulating SHSTK and IBT would also require significant complexity, e.g.
to track and update branch state for IBT, and shadow stack state for SHSTK.
Given that emulating large swaths of the guest code stream isn't necessary on
modern CPUs, punt on emulating instructions that meaningful impact or consume
SHSTK or IBT. However, instead of doing nothing, explicitly reject emulation
of such instructions so that KVM's emulator can't be abused to circumvent CET.
Disable support for SHSTK and IBT if KVM is configured such that emulation of
arbitrary guest instructions may be required, specifically if Unrestricted
Guest (Intel only) is disabled, or if KVM will emulate a guest.MAXPHYADDR that
is smaller than host.MAXPHYADDR.
Lastly disable SHSTK support if shadow paging is enabled, as the protections
for the shadow stack are novel (shadow stacks require Writable=0,Dirty=1, so
that they can't be directly modified by software), i.e. would require
non-trivial support in the Shadow MMU.
Note, AMD CPUs currently only support SHSTK. Explicitly disable IBT support
so that KVM doesn't over-advertise if AMD CPUs add IBT, and virtualizing IBT
in SVM requires KVM modifications.
KVM selftests changes for 6.18
- Add #DE coverage in the fastops test (the only exception that's guest-
triggerable in fastop-emulated instructions).
- Fix PMU selftests errors encountered on Granite Rapids (GNR), Sierra
Forest (SRF) and Clearwater Forest (CWF).
- Minor cleanups and improvements
KVM/riscv changes for 6.18
- Added SBI FWFT extension for Guest/VM with misaligned
delegation and pointer masking PMLEN features
- Added ONE_REG interface for SBI FWFT extension
- Added Zicbop and bfloat16 extensions for Guest/VM
- Enabled more common KVM selftests for RISC-V such as
access_tracking_perf_test, dirty_log_perf_test,
memslot_modification_stress_test, memslot_perf_test,
mmu_stress_test, and rseq_test
- Added SBI v3.0 PMU enhancements in KVM and perf driver
* kvm-arm64/selftests-6.18:
: .
: KVM/arm64 selftest updates for 6.18:
:
: - Large update to run EL1 selftests at EL2 when possible
: (20250917212044.294760-1-oliver.upton@linux.dev)
:
: - Work around lack of ID_AA64MMFR4_EL1 trapping on CPUs
: without FEAT_FGT
: (20250923173006.467455-1-oliver.upton@linux.dev)
:
: - Additional fixes and cleanups
: (20250920-kvm-arm64-id-aa64isar3-el1-v1-0-1764c1c1c96d@kernel.org)
: .
KVM: arm64: selftests: Cover ID_AA64ISAR3_EL1 in set_id_regs
KVM: arm64: selftests: Remove a duplicate register listing in set_id_regs
KVM: arm64: selftests: Cope with arch silliness in EL2 selftest
KVM: arm64: selftests: Add basic test for running in VHE EL2
KVM: arm64: selftests: Enable EL2 by default
KVM: arm64: selftests: Initialize HCR_EL2
KVM: arm64: selftests: Use the vCPU attr for setting nr of PMU counters
KVM: arm64: selftests: Use hyp timer IRQs when test runs at EL2
KVM: arm64: selftests: Select SMCCC conduit based on current EL
KVM: arm64: selftests: Provide helper for getting default vCPU target
KVM: arm64: selftests: Alias EL1 registers to EL2 counterparts
KVM: arm64: selftests: Create a VGICv3 for 'default' VMs
KVM: arm64: selftests: Add unsanitised helpers for VGICv3 creation
KVM: arm64: selftests: Add helper to check for VGICv3 support
KVM: arm64: selftests: Initialize VGICv3 only once
KVM: arm64: selftests: Provide kvm_arch_vm_post_create() in library code
Signed-off-by: Marc Zyngier <maz@kernel.org>
Take advantage of VHE to implicitly promote KVM selftests to run at EL2
with only slight modification. Update the smccc_filter test to account
for this now that the EL2-ness of a VM is visible to tests.
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Arch timer registers are redirected to their hypervisor counterparts
when running in VHE EL2. This is great, except for the fact that the
hypervisor timers use different PPIs. Use the correct INTIDs when that
is the case.
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
HVCs are taken within the VM when EL2 is in use. Ensure tests use the
SMC instruction when running at EL2 to interact with the host.
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
The default vCPU target in KVM selftests is pretty boring in that it
doesn't enable any vCPU features. Expose a helper for getting the
default target to prepare for cramming in more features. Call
KVM_ARM_PREFERRED_TARGET directly from get-reg-list as it needs
fine-grained control over feature flags.
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Reviewed-by: Itaru Kitayama <itaru.kitayama@fujitsu.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
FEAT_VHE has the somewhat nice property of implicitly redirecting EL1
register aliases to their corresponding EL2 representations when E2H=1.
Unfortunately, there's no such abstraction for userspace and EL2
registers are always accessed by their canonical encoding.
Introduce a helper that applies EL2 redirections to sysregs and use
aggressive inlining to catch misuse at compile time. Go a little past
the architectural definition for ease of use for test authors (e.g. the
stack pointer).
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Start creating a VGICv3 by default unless explicitly opted-out by the
test. While having an interrupt controller is nice, the real benefit
here is clearing a hurdle for EL2 VMs which mandate the presence of a
VGIC.
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
vgic_v3_setup() has a good bit of sanity checking internally to ensure
that vCPUs have actually been created and match the dimensioning of the
vgic itself. Spin off an unsanitised setup and initialization helper so
vgic initialization can be wired in around a 'default' VM's vCPU
creation.
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Introduce a proper predicate for probing VGICv3 by performing a 'test'
creation of the device on a dummy VM.
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
In order to compel the default usage of EL2 in selftests, move
kvm_arch_vm_post_create() to library code and expose an opt-in for using
MTE by default.
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Add a selftest to verify reads and writes to various MSRs, from both the
guest and host, and expect success/failure based on whether or not the
vCPU supports the MSR according to supported CPUID.
Note, this test is extremely similar to KVM-Unit-Test's "msr" test, but
provides more coverage with respect to host accesses, and will be extended
to provide addition testing of CPUID-based features, save/restore lists,
and KVM_{G,S}ET_ONE_REG, all which are extremely difficult to validate in
KUT.
If kvm.ignore_msrs=true, skip the unsupported and reserved testcases as
KVM's ABI is a mess; what exactly is supposed to be ignored, and when,
varies wildly.
Reviewed-by: Chao Gao <chao.gao@intel.com>
Link: https://lore.kernel.org/r/20250919223258.1604852-46-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Add a basic test corrupting a level-2 table entry to check that
the resulting abort is a SEA on a PTW at level-3.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Add support for handling #DE (divide error) exceptions in KVM selftests
so that the fastops test can verify KVM correctly handles #DE when
emulating DIV or IDIV on behalf of the guest. Morph #DE to 0xff (i.e.
to -1) as a mostly-arbitrary vector to indicate #DE, so that '0' (the
real #DE vector) can still be used to indicate "no exception".
Link: https://lore.kernel.org/r/20250909202835.333554-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
KVM/arm64 changes for 6.17, round #1
- Host driver for GICv5, the next generation interrupt controller for
arm64, including support for interrupt routing, MSIs, interrupt
translation and wired interrupts.
- Use FEAT_GCIE_LEGACY on GICv5 systems to virtualize GICv3 VMs on
GICv5 hardware, leveraging the legacy VGIC interface.
- Userspace control of the 'nASSGIcap' GICv3 feature, allowing
userspace to disable support for SGIs w/o an active state on hardware
that previously advertised it unconditionally.
- Map supporting endpoints with cacheable memory attributes on systems
with FEAT_S2FWB and DIC where KVM no longer needs to perform cache
maintenance on the address range.
- Nested support for FEAT_RAS and FEAT_DoubleFault2, allowing the guest
hypervisor to inject external aborts into an L2 VM and take traps of
masked external aborts to the hypervisor.
- Convert more system register sanitization to the config-driven
implementation.
- Fixes to the visibility of EL2 registers, namely making VGICv3 system
registers accessible through the VGIC device instead of the ONE_REG
vCPU ioctls.
- Various cleanups and minor fixes.
KVM selftests changes for 6.17
- Fix a comment typo.
- Verify KVM is loaded when getting any KVM module param so that attempting to
run a selftest without kvm.ko loaded results in a SKIP message about KVM not
being loaded/enabled, versus some random parameter not existing.
- SKIP tests that hit EACCES when attempting to access a file, with a "Root
required?" help message. In most cases, the test just needs to be run with
elevated permissions.
KVM x86 misc changes for 6.17
- Prevert the host's DEBUGCTL.FREEZE_IN_SMM (Intel only) when running the
guest. Failure to honor FREEZE_IN_SMM can bleed host state into the guest.
- Explicitly check vmcs12.GUEST_DEBUGCTL on nested VM-Enter (Intel only) to
prevent L1 from running L2 with features that KVM doesn't support, e.g. BTF.
- Intercept SPEC_CTRL on AMD if the MSR shouldn't exist according to the
vCPU's CPUID model.
- Rework the MSR interception code so that the SVM and VMX APIs are more or
less identical.
- Recalculate all MSR intercepts from the "source" on MSR filter changes, and
drop the dedicated "shadow" bitmaps (and their awful "max" size defines).
- WARN and reject loading kvm-amd.ko instead of panicking the kernel if the
nested SVM MSRPM offsets tracker can't handle an MSR.
- Advertise support for LKGS (Load Kernel GS base), a new instruction that's
loosely related to FRED, but is supported and enumerated independently.
- Fix a user-triggerable WARN that syzkaller found by stuffing INIT_RECEIVED,
a.k.a. WFS, and then putting the vCPU into VMX Root Mode (post-VMXON). Use
the same approach KVM uses for dealing with "impossible" emulation when
running a !URG guest, and simply wait until KVM_RUN to detect that the vCPU
has architecturally impossible state.
- Add KVM_X86_DISABLE_EXITS_APERFMPERF to allow disabling interception of
APERF/MPERF reads, so that a "properly" configured VM can "virtualize"
APERF/MPERF (with many caveats).
- Reject KVM_SET_TSC_KHZ if vCPUs have been created, as changing the "default"
frequency is unsupported for VMs with a "secure" TSC, and there's no known
use case for changing the default frequency for other VM types.
Expand kvm_pin_this_task_to_pcpu() into a set of APIs to allow pinning a
task (or self) to a CPU (any or specific). This will allow deduplicating
code throughout a variety of selftests.
Opportunistically use "self" instead of "this_task" as it is both more
concise and less ambiguous.
Link: https://lore.kernel.org/r/20250626001225.744268-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
