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charset="utf-8" Clear the cleanbits only when the VMCB is used on a different pCPU rather than on every context switch to the vCPU. This follows the APM guideline for when to clear the cleanbits: "The hypervisor executes the guest on a different CPU core than one used the last time that guest was executed." Signed-off-by: Ross Lagerwall Reviewed-by: Jason Andryuk --- xen/arch/x86/hvm/svm/svm.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/xen/arch/x86/hvm/svm/svm.c b/xen/arch/x86/hvm/svm/svm.c index 71e48351f22c..4e22322f4b42 100644 --- a/xen/arch/x86/hvm/svm/svm.c +++ b/xen/arch/x86/hvm/svm/svm.c @@ -890,7 +890,6 @@ static void cf_check svm_ctxt_switch_from(struct vcpu *= v) =20 static void cf_check svm_ctxt_switch_to(struct vcpu *v) { - struct vmcb_struct *vmcb =3D v->arch.hvm.svm.vmcb; int cpu =3D smp_processor_id(); =20 /* @@ -908,7 +907,6 @@ static void cf_check svm_ctxt_switch_to(struct vcpu *v) =20 svm_restore_dr(v); =20 - vmcb->cleanbits.raw =3D 0; svm_tsc_ratio_load(v); =20 if ( cpu_has_msr_tsc_aux ) @@ -953,6 +951,7 @@ static void noreturn cf_check svm_do_resume(void) hvm_migrate_pirqs(v); /* Migrating to another ASID domain. Request a new ASID. */ hvm_asid_flush_vcpu(v); + vmcb->cleanbits.raw =3D 0; } =20 if ( !vcpu_guestmode && !vlapic_hw_disabled(vlapic) ) --=20 2.55.0