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From: Gleb Natapov <gleb@redhat.com>
To: Kevin Wolf <kwolf@redhat.com>
Cc: kvm@vger.kernel.org
Subject: Re: [RFC PATCH] emulator: Fix task switch into/out of VM86
Date: Tue, 10 Jan 2012 12:17:36 +0200	[thread overview]
Message-ID: <20120110101736.GL2167@redhat.com> (raw)
In-Reply-To: <4F0C04A6.1080705@redhat.com>

On Tue, Jan 10, 2012 at 10:28:06AM +0100, Kevin Wolf wrote:
> Am 10.01.2012 10:01, schrieb Gleb Natapov:
> > On Mon, Jan 09, 2012 at 09:10:10PM +0100, Kevin Wolf wrote:
> >> * This works with VMX, but with SVM I have an additional problem: When
> >>   trying to exit VM86 (usually by an exception) through a task gate in
> >>   the IDT, the code runs into the reason = TASK_SWITCH_CALL path. I
> >>   searched a bit in the documentation, but didn't find any obvious way
> >>   to fix this.
> >>
> > Hmm, so exit_int_info is invalid during task switch exit even though
> > task switch was caused by an exception. I wonder is this the case when
> > vcpu is not in vm86 mode too?
> 
> No idea, I would have to try it out.
> 
IIRC (again) 32 bit Linux kernel configures double fault as a task gate,
so causing #DF on 32 bit kernel guest should be enough to test that.
 
--
			Gleb.

  reply	other threads:[~2012-01-10 10:17 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-01-09 20:10 [RFC PATCH] emulator: Fix task switch into/out of VM86 Kevin Wolf
2012-01-10  3:08 ` Takuya Yoshikawa
2012-01-10  4:07 ` Takuya Yoshikawa
2012-01-10  9:01 ` Gleb Natapov
2012-01-10  9:28   ` Kevin Wolf
2012-01-10 10:17     ` Gleb Natapov [this message]
2012-01-10 11:25     ` Kevin Wolf
2012-01-10 11:30       ` Gleb Natapov
2012-01-10 17:51         ` Joerg Roedel
2012-01-16 15:37           ` Kevin Wolf
2012-01-16 15:57             ` Joerg Roedel

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