linux/arch
Sandipan Das 5a1bde46f9 kvm: x86/cpuid: Only provide CPUID leaf 0xA if host has architectural PMU
On some x86 processors, CPUID leaf 0xA provides information
on Architectural Performance Monitoring features. It
advertises a PMU version which Qemu uses to determine the
availability of additional MSRs to manage the PMCs.

Upon receiving a KVM_GET_SUPPORTED_CPUID ioctl request for
the same, the kernel constructs return values based on the
x86_pmu_capability irrespective of the vendor.

This leaf and the additional MSRs are not supported on AMD
and Hygon processors. If AMD PerfMonV2 is detected, the PMU
version is set to 2 and guest startup breaks because of an
attempt to access a non-existent MSR. Return zeros to avoid
this.

Fixes: a6c06ed1a6 ("KVM: Expose the architectural performance monitoring CPUID leaf")
Reported-by: Vasant Hegde <vasant.hegde@amd.com>
Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Message-Id: <3fef83d9c2b2f7516e8ff50d60851f29a4bcb716.1651058600.git.sandipan.das@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-03 08:05:08 -04:00
..
alpha Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2022-04-01 19:57:03 -07:00
arc ptrace: Cleanups for v5.18 2022-03-28 17:29:53 -07:00
arm ARM fixes for 5.18-rc1: 2022-04-03 10:17:48 -07:00
arm64 KVM: fix bad user ABI for KVM_EXIT_SYSTEM_EVENT 2022-04-29 12:38:22 -04:00
csky ptrace: Cleanups for v5.18 2022-03-28 17:29:53 -07:00
h8300 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2022-04-01 19:57:03 -07:00
hexagon ptrace: Cleanups for v5.18 2022-03-28 17:29:53 -07:00
ia64 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2022-04-01 19:57:03 -07:00
m68k Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2022-04-01 19:57:03 -07:00
microblaze Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
mips - build fix for gpio 2022-04-02 12:14:38 -07:00
nios2 ptrace: Cleanups for v5.18 2022-03-28 17:29:53 -07:00
openrisc ptrace: Cleanups for v5.18 2022-03-28 17:29:53 -07:00
parisc Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
powerpc Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2022-04-01 19:57:03 -07:00
riscv KVM: fix bad user ABI for KVM_EXIT_SYSTEM_EVENT 2022-04-29 12:38:22 -04:00
s390 * Only do MSR filtering for MSRs accessed by rdmsr/wrmsr 2022-04-02 12:09:02 -07:00
sh Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2022-04-01 19:57:03 -07:00
sparc Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
um Kbuild fixes for v5.18 2022-04-02 12:33:31 -07:00
x86 kvm: x86/cpuid: Only provide CPUID leaf 0xA if host has architectural PMU 2022-05-03 08:05:08 -04:00
xtensa Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
.gitignore
Kconfig Networking fixes for 5.18-rc1 and rethook patches. 2022-03-31 11:23:31 -07:00