public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
* [PATCH] KVM: nVMX: fixes for preemption timer migration
@ 2020-07-09 17:15 Paolo Bonzini
  2020-07-09 17:23 ` Jim Mattson
  0 siblings, 1 reply; 4+ messages in thread
From: Paolo Bonzini @ 2020-07-09 17:15 UTC (permalink / raw)
  To: linux-kernel, kvm; +Cc: bsd, Makarand Sonare

Commit 850448f35aaf ("KVM: nVMX: Fix VMX preemption timer migration",
2020-06-01) accidentally broke nVMX live migration from older version
by changing the userspace ABI.  Restore it and, while at it, ensure
that vmx->nested.has_preemption_timer_deadline is always initialized
according to the KVM_STATE_VMX_PREEMPTION_TIMER_DEADLINE flag.

Cc: Makarand Sonare <makarandsonare@google.com>
Fixes: 850448f35aaf ("KVM: nVMX: Fix VMX preemption timer migration")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/include/uapi/asm/kvm.h | 5 +++--
 arch/x86/kvm/vmx/nested.c       | 3 ++-
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index 17c5a038f42d..0780f97c1850 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -408,14 +408,15 @@ struct kvm_vmx_nested_state_data {
 };
 
 struct kvm_vmx_nested_state_hdr {
-	__u32 flags;
 	__u64 vmxon_pa;
 	__u64 vmcs12_pa;
-	__u64 preemption_timer_deadline;
 
 	struct {
 		__u16 flags;
 	} smm;
+
+	__u32 flags;
+	__u64 preemption_timer_deadline;
 };
 
 struct kvm_svm_nested_state_data {
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index b26655104d4a..3fc2411edc92 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -6180,7 +6180,8 @@ static int vmx_set_nested_state(struct kvm_vcpu *vcpu,
 		vmx->nested.has_preemption_timer_deadline = true;
 		vmx->nested.preemption_timer_deadline =
 			kvm_state->hdr.vmx.preemption_timer_deadline;
-	}
+	} else
+		vmx->nested.has_preemption_timer_deadline = false;
 
 	if (nested_vmx_check_controls(vcpu, vmcs12) ||
 	    nested_vmx_check_host_state(vcpu, vmcs12) ||
-- 
2.26.2


^ permalink raw reply related	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2020-07-09 17:36 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2020-07-09 17:15 [PATCH] KVM: nVMX: fixes for preemption timer migration Paolo Bonzini
2020-07-09 17:23 ` Jim Mattson
2020-07-09 17:26   ` Paolo Bonzini
2020-07-09 17:36   ` Bandan Das

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox