[PATCH 5.10 032/167] KVM: x86/pmu: Clear anythread deprecated bit when 0xa leaf is unsupported on the SVM

From: Greg Kroah-Hartman
Date: Mon Jul 26 2021 - 12:17:57 EST


From: Like Xu <like.xu.linux@xxxxxxxxx>

[ Upstream commit 7234c362ccb3c2228f06f19f93b132de9cfa7ae4 ]

The AMD platform does not support the functions Ah CPUID leaf. The returned
results for this entry should all remain zero just like the native does:

AMD host:
0x0000000a 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000 edx=0x00000000
(uncanny) AMD guest:
0x0000000a 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000 edx=0x00008000

Fixes: cadbaa039b99 ("perf/x86/intel: Make anythread filter support conditional")
Signed-off-by: Like Xu <likexu@xxxxxxxxxxx>
Message-Id: <20210628074354.33848-1-likexu@xxxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/x86/kvm/cpuid.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 7a3fbf3b796e..41b0dc37720e 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -684,7 +684,8 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)

edx.split.num_counters_fixed = min(cap.num_counters_fixed, MAX_FIXED_COUNTERS);
edx.split.bit_width_fixed = cap.bit_width_fixed;
- edx.split.anythread_deprecated = 1;
+ if (cap.version)
+ edx.split.anythread_deprecated = 1;
edx.split.reserved1 = 0;
edx.split.reserved2 = 0;

--
2.30.2