From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: [PATCH] KVM: x86: Fix guest single-stepping while interruptible
Date: Mon, 19 Oct 2009 16:52:39 -0200
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References: <4ADAFAFC.2010603@web.de>
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Cc: Avi Kivity <avi@redhat.com>, kvm-devel <kvm@vger.kernel.org>
To: Jan Kiszka <jan.kiszka@web.de>
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On Sun, Oct 18, 2009 at 01:24:44PM +0200, Jan Kiszka wrote:
> Commit 705c5323 opened the doors of hell by unconditionally injecting
> single-step flags as long as guest_debug signaled this. This doesn't
> work when the guest branches into some interrupt or exception handler
> and triggers a vmexit with flag reloading.
> 
> Fix it by saving cs:rip when user space requests single-stepping and
> restricting the trace flag injection to this guest code position.
> 
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> ---
> 
>  arch/x86/include/asm/kvm_host.h |    4 +++
>  arch/x86/kvm/x86.c              |   47 +++++++++++++++++++++++----------------
>  2 files changed, 32 insertions(+), 19 deletions(-)

Applied, thanks.