The Architecture LBR does not have MSR_LBR_TOS (0x000001c9). KVM will
generate #GP for this MSR access, thereby preventing the initialization
of the guest LBR.
Cc: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Fixes: 47125db27e47 ("perf/x86/intel/lbr: Support Architectural LBR")
Signed-off-by: Like Xu <like.xu@xxxxxxxxxxxxxxx>
Reviewed-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Reviewed-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
---
arch/x86/events/intel/core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index 7bb96ac87615..0338e354826d 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -5568,7 +5568,8 @@ __init int intel_pmu_init(void)
* Check all LBR MSR here.
* Disable LBR access if any LBR MSRs can not be accessed.
*/
- if (x86_pmu.lbr_nr && !check_msr(x86_pmu.lbr_tos, 0x3UL))
+ if (x86_pmu.lbr_nr && !boot_cpu_has(X86_FEATURE_ARCH_LBR) &&
+ !check_msr(x86_pmu.lbr_tos, 0x3UL))
x86_pmu.lbr_nr = 0;
for (i = 0; i < x86_pmu.lbr_nr; i++) {
if (!(check_msr(x86_pmu.lbr_from + i, 0xffffUL) &&
--
2.29.2
