From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.xen@gmail.com>
Subject: Re: The entry of Xen's exception handler
Date: Tue, 02 Oct 2012 22:30:49 +0100
Message-ID: <CC911B99.4093B%keir.xen@gmail.com>
References: <CAJJWZczK3+KWcuk8yvjr6AXtkBkPgzUTrnqp0+FhQcf=s00e_A@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
Return-path: <xen-devel-bounces@lists.xen.org>
In-Reply-To: <CAJJWZczK3+KWcuk8yvjr6AXtkBkPgzUTrnqp0+FhQcf=s00e_A@mail.gmail.com>
List-Unsubscribe: <http://lists.xen.org/cgi-bin/mailman/options/xen-devel>,
	<mailto:xen-devel-request@lists.xen.org?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xen.org>
List-Help: <mailto:xen-devel-request@lists.xen.org?subject=help>
List-Subscribe: <http://lists.xen.org/cgi-bin/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xen.org?subject=subscribe>
Sender: xen-devel-bounces@lists.xen.org
Errors-To: xen-devel-bounces@lists.xen.org
To: Xinxin Jin <xinxinjin89@gmail.com>, Xen-devel@lists.xen.org
List-Id: xen-devel@lists.xenproject.org

On 02/10/2012 21:51, "Xinxin Jin" <xinxinjin89@gmail.com> wrote:

> Hi, I am trying to understand the exception handler of Xen. In
> xen/arch/x86/x86_64/entry.S, the entry of the page fault handler is :
> =

> ENTRY(page_fault)
> =A0 =A0 =A0 =A0 movl =A0$TRAP_page_fault,4(%rsp)
> =A0 =A0 =A0 =A0 jmp =A0 handle_exception
> =

> Here I did not get why to put the exception vector ($TRAP_page_fault) to =
stack
> before calling handle_exception?

Otherwise handle_exception would not know which type of exception it was
handling, would it.

 -- Keir

> Thanks,