hi, the HPE server can do POST tracing and have enabled LBR tracing during the boot, which makes check_msr fail falsly.
It looks like check_msr code was added only to check on guests MSR access, would it be then ok to disable check_msr for real hardware? (as in patch below) We could also check if LBR tracing is enabled and make appropriate checks, but this change is simpler ;-) ideas? thanks, jirka --- arch/x86/events/intel/core.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index 71001f005bfe..1194ae7e1992 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -20,6 +20,7 @@ #include <asm/intel-family.h> #include <asm/apic.h> #include <asm/cpu_device_id.h> +#include <asm/hypervisor.h> #include "../perf_event.h" @@ -4050,6 +4051,13 @@ static bool check_msr(unsigned long msr, u64 mask) { u64 val_old, val_new, val_tmp; + /* + * Disable the check for real HW, so we don't + * mess up with potentionaly enabled regs. + */ + if (hypervisor_is_type(X86_HYPER_NATIVE)) + return true; + /* * Read the current value, change it and read it back to see if it * matches, this is needed to detect certain hardware emulators -- 2.21.0