All of lore.kernel.org
 help / color / mirror / Atom feed
From: Matteo Signorini <signorinimatteo@gmail.com>
To: kvm@vger.kernel.org
Subject: ms_sysenter_eip zero value
Date: Sun, 23 Jan 2011 12:25:48 +0100	[thread overview]
Message-ID: <AANLkTi=S_xGDvsqX95swMuyv4EODRbVRnxJiik7A+zv3@mail.gmail.com> (raw)

Hi,

I'm having some problems understanding the sysenter instruction.
As far as I know, in order to successfully call the sysenter instruction,
MSR_IA32_SYSENTER_CS and MSR_IA32_SYSENTER_EIP registers have to be
correctly set.

So I printed the value of such registers while the VM was running but
the output is 0 for both.

now:

1) I'm having this problem ONLY with the Intel CPU (vmx.c source code).
When I run the same code on an AMD CPU (svm.c source code)
MSR_IA32_SYSENTER_EIP and MSR_IA32_SYSENTER_CS contain nonzero values.

2) I am 100% sure the guest is not executing an int80 but a sysenter

so there is something here I can't understand...
please help me solving this problem.

thank you for enlightening me on this issue,
Matteo

             reply	other threads:[~2011-01-23 11:25 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-01-23 11:25 Matteo Signorini [this message]
2011-01-26 11:24 ` ms_sysenter_eip zero value Avi Kivity
2011-01-27 13:01   ` Matteo

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='AANLkTi=S_xGDvsqX95swMuyv4EODRbVRnxJiik7A+zv3@mail.gmail.com' \
    --to=signorinimatteo@gmail.com \
    --cc=kvm@vger.kernel.org \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.