From: Like Xu <likexu@xxxxxxxxxxx> [ Upstream commit 5863702561e625903ec678551cb056a4b19e0b8a ] Just like what we do in the x86_get_event_constraints(), the PERF_X86_EVENT_LBR_SELECT flag should also be propagated to event->hw.flags so that the host lbr driver can save/restore MSR_LBR_SELECT for the special vlbr event created by KVM or BPF. Fixes: 097e4311cda9 ("perf/x86: Add constraint to create guest LBR event without hw counter") Reported-by: Wanpeng Li <wanpengli@xxxxxxxxxxx> Signed-off-by: Like Xu <likexu@xxxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Tested-by: Wanpeng Li <wanpengli@xxxxxxxxxxx> Link: https://lore.kernel.org/r/20211103091716.59906-1-likexu@xxxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/x86/events/intel/core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index bc3f97f834011..c7f1cc433a6aa 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -2999,8 +2999,10 @@ intel_vlbr_constraints(struct perf_event *event) { struct event_constraint *c = &vlbr_constraint; - if (unlikely(constraint_match(c, event->hw.config))) + if (unlikely(constraint_match(c, event->hw.config))) { + event->hw.flags |= c->flags; return c; + } return NULL; } -- 2.33.0