From: Wanpeng Li <wanpengli@tencent.com>

MWAIT is advertised in host is not overcommitted scenario, however, PV
TLB/sched yield should be enabled in host overcommitted scenario. Let's 
add the MWAIT checking when enabling PV TLB/sched yield.

Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
---
 arch/x86/kernel/kvm.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index f734e3b0cfec..491e1d9ca750 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -463,6 +463,7 @@ static bool pv_tlb_flush_supported(void)
 	return (kvm_para_has_feature(KVM_FEATURE_PV_TLB_FLUSH) &&
 		!kvm_para_has_hint(KVM_HINTS_REALTIME) &&
 		kvm_para_has_feature(KVM_FEATURE_STEAL_TIME) &&
+		!boot_cpu_has(X86_FEATURE_MWAIT) &&
 		(num_possible_cpus() != 1));
 }
 
@@ -477,6 +478,7 @@ static bool pv_sched_yield_supported(void)
 	return (kvm_para_has_feature(KVM_FEATURE_PV_SCHED_YIELD) &&
 		!kvm_para_has_hint(KVM_HINTS_REALTIME) &&
 	    kvm_para_has_feature(KVM_FEATURE_STEAL_TIME) &&
+	    !boot_cpu_has(X86_FEATURE_MWAIT) &&
 	    (num_possible_cpus() != 1));
 }
 
-- 
2.25.1

Queued, thanks.

Paolo

Queued, thanks.

Paolo