KVM x86 fixes for 7.1-rcN
- Include the kernel's linux/mman.h in KVM selftests to ensure MADV_COLLAPSE
is defined, as older libc versions may not provide it.
- Include execinfo.h if and only if KVM selftests are building against glibc,
and provide a test_dump_stack() for non-glibc builds.
- Fudge around an RCU splat in the emegerncy reboot code that is technically
a legitimate flaw, but in practice is a non-issue and fixing the flaw, e.g.
by adding locking, would incur meaningful risk, i.e. do more harm than good.
- Rate-limit global clock updates once again (but without delayed work), as
KVM was subtly relying on the old rate-limiting for NPT correction to guard
against "update storms" when running without a master clock on systems with
overcommitted CPUs.
- Fix a brown paper bag goof where KVM checked if ERAPS is "dirty" instead of
marking it dirty when emulating INVPCID.
- Flush the TLB when transitioning from xAVIC => x2AVIC to ensure the CPU TLB
doesn't contain AVIC-tagged entries for the APIC base GPA.
<bits/endian.h> is a glibc-internal header that explicitly states it
should never be included directly:
#error "Never use <bits/endian.h> directly; include <endian.h> instead."
Replace it with the correct public header <endian.h> which works on
all C libraries including musl. Building KVM selftests with musl-gcc
fails with:
lib/elf.c:10:10: fatal error: bits/endian.h: No such file or directory
Fixes: 6089ae0bd5 ("kvm: selftests: add sync_regs_test")
Signed-off-by: Hisam Mehboob <hisamshar@gmail.com>
Message-ID: <20260409164020.1575176-4-hisamshar@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The backtrace() function and execinfo.h are GNU extensions available
in glibc but not in non-glibc C libraries such as musl. Building KVM
selftests with musl-gcc fails with:
lib/assert.c:9:10: fatal error: execinfo.h: No such file or directory
Fix this by guarding the inclusion of execinfo.h and the stack dumping
logic under #ifdef __GLIBC__. For non-glibc builds, provide a local
stub for test_dump_stack().
Suggested-by: Aqib Faruqui <aqibaf@amazon.com>
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Hisam Mehboob <hisamshar@gmail.com>
Link: https://patch.msgid.link/20260409153846.1502656-2-hisamshar@gmail.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Include both linux/mman.h (the kernel provided version) and sys/mman.h (the
libc provided version) throughout KVM selftests, by way of kvm_syscalls.h
(which should have been including sys/mman.h anyways). Pulling in the
kernel's version fixes compilation errors with the guest_memfd test on
older versions of libc due to a recent commit adding MADV_COLLAPSE testing.
In file included from include/kvm_util.h:8,
from guest_memfd_test.c:21:
guest_memfd_test.c: In function ‘test_collapse’:
guest_memfd_test.c:219:47: error: ‘MADV_COLLAPSE’ undeclared (first use in this function); did you mean ‘MADV_COLD’?
219 | TEST_ASSERT_EQ(madvise(mem, pmd_size, MADV_COLLAPSE), -1);
| ^~~~~~~~~~~~~
include/test_util.h:62:16: note: in definition of macro ‘TEST_ASSERT_EQ’
62 | typeof(a) __a = (a); \
| ^
guest_memfd_test.c:219:47: note: each undeclared identifier is reported only once for each function it appears in
219 | TEST_ASSERT_EQ(madvise(mem, pmd_size, MADV_COLLAPSE), -1);
| ^~~~~~~~~~~~~
include/test_util.h:62:16: note: in definition of macro ‘TEST_ASSERT_EQ’
62 | typeof(a) __a = (a); \
| ^
Route the includes through kvm_syscalls.h to try and avoid a future game
of whack-a-mole, i.e. so that future expansion of test coverage doesn't run
into the same problem.
To discourage use of sys/mman.h, opportunistically include the kernel's
version of mman.h in test_util.h as it only needs MAP_SHARED, i.e. only
needs the full set of kernel defs, not the libc syscall wrappers.
Fixes: 9830209b4a ("KVM: selftests: Test MADV_COLLAPSE on guest_memfd")
Reported-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Closes: https://lore.kernel.org/all/20260427204313.50741-1-rick.p.edgecombe@intel.com
Link: https://patch.msgid.link/20260428012503.1213654-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Replace all variations of "paddr" variables in KVM selftests with "gpa",
with the exception of the ELF structures, as those fields are not specific
to guest virtual addresses, to complete the conversion from vm_paddr_t to
gpa_t.
No functional change intended.
Link: https://patch.msgid.link/20260420212004.3938325-20-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Replace all variations of "vaddr" variables in KVM selftests with "gva",
with the exception of the ELF structures, as those fields are not specific
to guest virtual addresses, to complete the conversion from vm_vaddr_t to
gva_t.
Opportunistically use gva_t instead of u64 for relevant variables, and
fixup indentation as appropriate.
No functional change intended.
Link: https://patch.msgid.link/20260420212004.3938325-17-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Now that KVM selftests use gva_t instead of vm_vaddr_t, rename the helper
for populating the initial GVA bitmap to drop the defunct terminology and
use "vm" for the scope.
Opportunistically fixup the declaration of the API, which has been broken
since day 1. The flaw went unnoticed because the sole caller is defined
after the weak version, i.e. can see the prototype without a previous
declaration.
No functional change intended.
Fixes: e8b9a055fa ("KVM: arm64: selftests: Align VA space allocator with TTBR0")
Link: https://patch.msgid.link/20260420212004.3938325-14-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Now that KVM selftests use gva_t instead of vm_vaddr_t, rename the API
for finding an unused range of virtual memory to drop the defunct
terminology and use "vm" for the scope.
Opportunistically clean up the function comment to drop superfluous
and redundant information.
No functional change intended.
Link: https://patch.msgid.link/20260420212004.3938325-13-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Now that KVM selftests use gva_t instead of vm_vaddr_t, drop "vaddr_" from
the core memory allocation APIs as the information is extraneous and does
more harm than good. E.g. the APIs don't _just_ allocate virtual memory,
they allocate backing physical memory and install mappings in the guest
page tables. And as proven by kmalloc() and malloc(), developers generally
expect that allocations come with a working virtual address.
Opportunistically clean up the function comment for vm_alloc(), and drop
the misleading and superfluous comments for its wrappers.
No functional change intended.
Link: https://patch.msgid.link/20260420212004.3938325-12-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Use u8 instead of uint8_t to make the KVM selftests code more concise
and more similar to the kernel (since selftests are primarily developed
by kernel developers).
This commit was generated with the following command:
git ls-files tools/testing/selftests/kvm | xargs sed -i 's/uint8_t/u8/g'
Then by manually adjusting whitespace to make checkpatch.pl happy.
No functional change intended.
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://patch.msgid.link/20260420212004.3938325-11-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Use s16 instead of int16_t to make the KVM selftests code more concise
and more similar to the kernel (since selftests are primarily developed
by kernel developers).
This commit was generated with the following command:
git ls-files tools/testing/selftests/kvm | xargs sed -i 's/int16_t/s16/g'
Then by manually adjusting whitespace to make checkpatch.pl happy.
No functional change intended.
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://patch.msgid.link/20260420212004.3938325-10-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Use u16 instead of uint16_t to make the KVM selftests code more concise
and more similar to the kernel (since selftests are primarily developed
by kernel developers).
This commit was generated with the following command:
git ls-files tools/testing/selftests/kvm | xargs sed -i 's/uint16_t/u16/g'
Then by manually adjusting whitespace to make checkpatch.pl happy.
No functional change intended.
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://patch.msgid.link/20260420212004.3938325-9-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Use u32 instead of uint32_t to make the KVM selftests code more concise
and more similar to the kernel (since selftests are primarily developed
by kernel developers).
This commit was generated with the following command:
git ls-files tools/testing/selftests/kvm | xargs sed -i 's/uint32_t/u32/g'
Then by manually adjusting whitespace to make checkpatch.pl happy.
No functional change intended.
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://patch.msgid.link/20260420212004.3938325-7-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Use s64 instead of int64_t to make the KVM selftests code more concise
and more similar to the kernel (since selftests are primarily developed
by kernel developers).
This commit was generated with the following command:
git ls-files tools/testing/selftests/kvm | xargs sed -i 's/int64_t/s64/g'
Then by manually adjusting whitespace to make checkpatch.pl happy.
No functional change intended.
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://patch.msgid.link/20260420212004.3938325-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Use u64 instead of uint64_t to make the KVM selftests code more concise
and more similar to the kernel (since selftests are primarily developed
by kernel developers).
This commit was generated with the following command:
git ls-files tools/testing/selftests/kvm | xargs sed -i 's/uint64_t/u64/g'
Then by manually adjusting whitespace to make checkpatch.pl happy.
Include <linux/types.h> in include/kvm_util_types.h, iinclude/test_util.h,
and include/x86/pmu.h to pick up the tools-defined u64. Arguably, all
headers (especially kvm_util_types.h) should have already been including
stdint.h to get uint64_t from the libc headers, but the missing dependency
only rears its head once KVM uses u64 instead of uint64_t.
No functional change intended.
Signed-off-by: David Matlack <dmatlack@google.com>
[sean: rename pread_uint64() => pread_u64, expand on types.h include]
Link: https://patch.msgid.link/20260420212004.3938325-5-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Replace all occurrences of vm_paddr_t with gpa_t to align with KVM code
and with the conversion helpers (e.g. addr_hva2gpa()).
This commit was generated with the following command:
git ls-files tools/testing/selftests/kvm | xargs sed -i 's/vm_paddr_/gpa_/g'
Then by manually adjusting whitespace to make checkpatch.pl happy.
No functional change intended.
Signed-off-by: David Matlack <dmatlack@google.com>
[sean: drop bogus changelog blurb about renaming functions]
Link: https://patch.msgid.link/20260420212004.3938325-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Replace all occurrences of vm_vaddr_t with gva_t to align with KVM code
and with the conversion helpers (e.g. addr_gva2hva()).
This commit was generated with the following command:
git ls-files tools/testing/selftests/kvm | xargs sed -i 's/vm_vaddr_/gva_/g'
Then by manually adjusting whitespace to make checkpatch.pl happy, and
dropping renames of functions that allocate memory within a given VM.
No functional change intended.
Signed-off-by: David Matlack <dmatlack@google.com>
[sean: drop renames of allocator APIs]
Link: https://patch.msgid.link/20260420212004.3938325-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
KVM nested SVM changes for 7.1 (with one common x86 fix)
- To minimize the probability of corrupting guest state, defer KVM's
non-architectural delivery of exception payloads (e.g. CR2 and DR6) until
consumption of the payload is imminent, and force delivery of the payload
in all paths where userspace saves relevant state.
- Use vcpu->arch.cr2 when updating vmcb12's CR2 on nested #VMEXIT to fix a
bug where L2's CR2 can get corrupted after a save/restore, e.g. if the VM
is migrated while L2 is faulting in memory.
- Fix a class of nSVM bugs where some fields written by the CPU are not
synchronized from vmcb02 to cached vmcb12 after VMRUN, and so are not
up-to-date when saved by KVM_GET_NESTED_STATE.
- Fix a class of bugs where the ordering between KVM_SET_NESTED_STATE and
KVM_SET_{S}REGS could cause vmcb02 to be incorrectly initialized after
save+restore.
- Add a variety of missing nSVM consistency checks.
- Fix several bugs where KVM failed to correctly update VMCB fields on nested
#VMEXIT.
- Fix several bugs where KVM failed to correctly synthesize #UD or #GP for
SVM-related instructions.
- Add support for save+restore of virtualized LBRs (on SVM).
- Refactor various helpers and macros to improve clarity and (hopefully) make
the code easier to maintain.
- Aggressively sanitize fields when copying from vmcb12 to guard against
unintentionally allowing L1 to utilize yet-to-be-defined features.
- Fix several bugs where KVM botched rAX legality checks when emulating SVM
instructions. Note, KVM is still flawed in that KVM doesn't address size
prefix overrides for 64-bit guests; this should probably be documented as a
KVM erratum.
- Fail emulation of VMRUN/VMLOAD/VMSAVE if mapping vmcb12 fails instead of
somewhat arbitrarily synthesizing #GP (i.e. don't bastardize AMD's already-
sketchy behavior of generating #GP if for "unsupported" addresses).
- Cache all used vmcb12 fields to further harden against TOCTOU bugs.
KVM selftests changes for 7.1
- Add support for Hygon CPUs in KVM selftests.
- Fix a bug in the MSR test where it would get false failures on AMD/Hygon
CPUs with exactly one of RDPID or RDTSCP.
- Add an MADV_COLLAPSE testcase for guest_memfd as a regression test for a
bug where the kernel would attempt to collapse guest_memfd folios against
KVM's will.
LoongArch KVM changes for v7.1
1. Use CSR_CRMD_PLV in kvm_arch_vcpu_in_kernel().
2. Let vcpu_is_preempted() a macro & some enhanments.
3. Add DMSINTC irqchip in kernel support.
4. Add KVM PMU test cases for tools/selftests.
Introduce a basic PMU test that verifies hardware event counting for
four performance counters. The test enables the events for CPU cycles,
instructions retired, branch instructions, and branch misses, runs a
fixed number of loops, and checks that the counter values fall within
expected ranges. It also validates that the host supports PMU and that
the VM feature is enabled.
Signed-off-by: Song Gao <gaosong@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Add helper macros and functions to read and write CPU configuration
registers (cpucfg) from the guest and from the VMM. This interface is
required in upcoming selftests for querying and setting CPU features,
such as PMU capabilities.
Signed-off-by: Song Gao <gaosong@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
