kvm.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Peter Feiner <pfeiner@google.com>
To: kvm@vger.kernel.org, drjones@redhat.com, pbonzini@redhat.com
Cc: pfeiner@google.com
Subject: [kvm-unit-tests PATCH] x86: vmx: fix definition of X86_CR4_VMXE
Date: Mon, 22 Feb 2016 15:40:36 -0800	[thread overview]
Message-ID: <1456184436-31168-1-git-send-email-pfeiner@google.com> (raw)

Was defined as 0x1 when it should have been 0x2000 (13th bit of CR4).
See Intel manual 23.7. 0x1 is the VME 'Virtual-8086 Mode Extensions'
bit, which the vmx tests don't exercise.

The correct bit was being set thanks to IA32_VMX_CR4_FIXED{0,1} MSRs
forcing it.

I hacked the test setup to forcibly un-set the bit and observed the
correct #UD VMXON behavior. Adding a test to verify the #UD behavior
is follow-up work.

Signed-off-by: Peter Feiner <pfeiner@google.com>
---
 lib/x86/processor.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/x86/processor.h b/lib/x86/processor.h
index 95cea1a..dff1689 100644
--- a/lib/x86/processor.h
+++ b/lib/x86/processor.h
@@ -21,7 +21,7 @@
 #define X86_CR0_WP     0x00010000
 #define X86_CR0_AM     0x00040000
 #define X86_CR0_PG     0x80000000
-#define X86_CR4_VMXE   0x00000001
+#define X86_CR4_VMXE   0x00002000
 #define X86_CR4_TSD    0x00000004
 #define X86_CR4_DE     0x00000008
 #define X86_CR4_PSE    0x00000010
-- 
2.7.0.rc3.207.g0ac5344


             reply	other threads:[~2016-02-22 23:40 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-02-22 23:40 Peter Feiner [this message]
2016-02-23 12:14 ` [kvm-unit-tests PATCH] x86: vmx: fix definition of X86_CR4_VMXE Paolo Bonzini

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=1456184436-31168-1-git-send-email-pfeiner@google.com \
    --to=pfeiner@google.com \
    --cc=drjones@redhat.com \
    --cc=kvm@vger.kernel.org \
    --cc=pbonzini@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).