This is a note to let you know that I've just added the patch titled
KVM: x86: emulating RDPID failure shall return #UD rather than #GP
to the 5.9-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-x86-emulating-rdpid-failure-shall-return-ud-rath.patch
and it can be found in the queue-5.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 67428a005dde22508783e0756569f356567bc9e6
Author: Robert Hoo <robert.hu@xxxxxxxxxxxxxxx>
Date: Fri Aug 28 10:23:42 2020 +0800
KVM: x86: emulating RDPID failure shall return #UD rather than #GP
[ Upstream commit a9e2e0ae686094571378c72d8146b5a1a92d0652 ]
Per Intel's SDM, RDPID takes a #UD if it is unsupported, which is more or
less what KVM is emulating when MSR_TSC_AUX is not available. In fact,
there are no scenarios in which RDPID is supposed to #GP.
Fixes: fb6d4d340e ("KVM: x86: emulate RDPID")
Signed-off-by: Robert Hoo <robert.hu@xxxxxxxxxxxxxxx>
Message-Id: <1598581422-76264-1-git-send-email-robert.hu@xxxxxxxxxxxxxxx>
Reviewed-by: Jim Mattson <jmattson@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 2f6510de6b0c0..85111cd0adcd0 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -3606,7 +3606,7 @@ static int em_rdpid(struct x86_emulate_ctxt *ctxt)
u64 tsc_aux = 0;
if (ctxt->ops->get_msr(ctxt, MSR_TSC_AUX, &tsc_aux))
- return emulate_gp(ctxt, 0);
+ return emulate_ud(ctxt);
ctxt->dst.val = tsc_aux;
return X86EMUL_CONTINUE;
}
