This is a note to let you know that I've just added the patch titled
KVM: SVM: #SMI interception must not skip the instruction
to the 5.13-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
kvm-svm-smi-interception-must-not-skip-the-instruction.patch
and it can be found in the queue-5.13 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 991afbbee8ac93b055a27477278a5fb556af1ff4 Mon Sep 17 00:00:00 2001
From: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
Date: Wed, 7 Jul 2021 15:50:58 +0300
Subject: KVM: SVM: #SMI interception must not skip the instruction
From: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
commit 991afbbee8ac93b055a27477278a5fb556af1ff4 upstream.
Commit 5ff3a351f687 ("KVM: x86: Move trivial instruction-based
exit handlers to common code"), unfortunately made a mistake of
treating nop_on_interception and nop_interception in the same way.
Former does truly nothing while the latter skips the instruction.
SMI VM exit handler should do nothing.
(SMI itself is handled by the host when we do STGI)
Fixes: 5ff3a351f687 ("KVM: x86: Move trivial instruction-based exit handlers to common code")
Signed-off-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
Message-Id: <20210707125100.677203-2-mlevitsk@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/kvm/svm/svm.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -2080,6 +2080,11 @@ static int nmi_interception(struct kvm_v
return 1;
}
+static int smi_interception(struct kvm_vcpu *vcpu)
+{
+ return 1;
+}
+
static int intr_interception(struct kvm_vcpu *vcpu)
{
++vcpu->stat.irq_exits;
@@ -3063,7 +3068,7 @@ static int (*const svm_exit_handlers[])(
[SVM_EXIT_EXCP_BASE + GP_VECTOR] = gp_interception,
[SVM_EXIT_INTR] = intr_interception,
[SVM_EXIT_NMI] = nmi_interception,
- [SVM_EXIT_SMI] = kvm_emulate_as_nop,
+ [SVM_EXIT_SMI] = smi_interception,
[SVM_EXIT_INIT] = kvm_emulate_as_nop,
[SVM_EXIT_VINTR] = interrupt_window_interception,
[SVM_EXIT_RDPMC] = kvm_emulate_rdpmc,
Patches currently in stable-queue which might be from mlevitsk@xxxxxxxxxx are
queue-5.13/kvm-svm-smi-interception-must-not-skip-the-instruction.patch
queue-5.13/kvm-nsvm-check-the-value-written-to-msr_vm_hsave_pa.patch
queue-5.13/kvm-svm-remove-init-intercept-handler.patch
