From: Vitaly Kuznetsov <vkuznets@redhat.com>
To: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org,
"Paolo Bonzini" <pbonzini@redhat.com>,
"Radim Krčmář" <rkrcmar@redhat.com>,
"Joerg Roedel" <joro@8bytes.org>,
"Jim Mattson" <jmattson@google.com>
Subject: [PATCH 1/5] x86: KVM: svm: don't pretend to advance RIP in case wrmsr_interception() results in #GP
Date: Thu, 1 Aug 2019 07:14:14 +0200 [thread overview]
Message-ID: <20190801051418.15905-2-vkuznets@redhat.com> (raw)
In-Reply-To: <20190801051418.15905-1-vkuznets@redhat.com>
svm->next_rip is only used by skip_emulated_instruction() and in case
kvm_set_msr() fails we rightfully don't do that. Move svm->next_rip
advancement to 'else' branch to avoid creating false impression that
it's always advanced (and make it look like rdmsr_interception()).
This is a preparatory change to removing hardcoded RIP advancement
from instruction intercepts, no functional change.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
arch/x86/kvm/svm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 7eafc6907861..7e843b340490 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -4447,13 +4447,13 @@ static int wrmsr_interception(struct vcpu_svm *svm)
msr.index = ecx;
msr.host_initiated = false;
- svm->next_rip = kvm_rip_read(&svm->vcpu) + 2;
if (kvm_set_msr(&svm->vcpu, &msr)) {
trace_kvm_msr_write_ex(ecx, data);
kvm_inject_gp(&svm->vcpu, 0);
return 1;
} else {
trace_kvm_msr_write(ecx, data);
+ svm->next_rip = kvm_rip_read(&svm->vcpu) + 2;
return kvm_skip_emulated_instruction(&svm->vcpu);
}
}
--
2.20.1
next prev parent reply other threads:[~2019-08-01 5:14 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-01 5:14 [PATCH 0/5] x86: KVM: svm: get rid of hardcoded instructions lengths Vitaly Kuznetsov
2019-08-01 5:14 ` Vitaly Kuznetsov [this message]
2019-08-01 5:14 ` [PATCH 2/5] x86: KVM: svm: avoid flooding logs when skip_emulated_instruction() fails Vitaly Kuznetsov
2019-08-01 5:14 ` [PATCH 3/5] x86: KVM: svm: clear interrupt shadow on all paths in skip_emulated_instruction() Vitaly Kuznetsov
2019-08-01 14:18 ` Sean Christopherson
2019-08-01 14:43 ` Vitaly Kuznetsov
2019-08-01 5:14 ` [PATCH 4/5] x86: KVM: add xsetbv to the emulator Vitaly Kuznetsov
2019-08-01 5:14 ` [PATCH 5/5] x86: KVM: svm: remove hardcoded instruction length from intercepts Vitaly Kuznetsov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190801051418.15905-2-vkuznets@redhat.com \
--to=vkuznets@redhat.com \
--cc=jmattson@google.com \
--cc=joro@8bytes.org \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=pbonzini@redhat.com \
--cc=rkrcmar@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).