From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Egger <Christoph.Egger@amd.com>
Subject: Re: [PATCH] xen: fix hypervisor crash with xentrace
Date: Wed, 6 Apr 2011 16:36:06 +0200
Message-ID: <4D9C7A56.8070007@amd.com>
References: <201104061632.02099.Christoph.Egger@amd.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="ISO-8859-1"; format=flowed
Content-Transfer-Encoding: 7bit
Return-path: <xen-devel-bounces@lists.xensource.com>
In-Reply-To: <201104061632.02099.Christoph.Egger@amd.com>
List-Unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xensource.com>
List-Help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-Subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
Sender: xen-devel-bounces@lists.xensource.com
Errors-To: xen-devel-bounces@lists.xensource.com
To: xen-devel@lists.xensource.com
List-Id: xen-devel@lists.xenproject.org

On 04/06/11 16:32, Christoph Egger wrote:
>
> Hi,
>
> Attached patch fixes hypervisor crashes when xentrace buffer gets initialized.

Forgot to mention this regression was introduced in c/s 
23134:f5d33782a57b by Jan Beulich.

>
> The xen backtraces I have seen are:
>
> (XEN) Xen call trace:
> (XEN)    [<ffff82c48025cf70>] early_stack+0x0/0x48
> (XEN)    [<ffff82c4801278d0>] tb_control+0x182/0x278
> (XEN)    [<ffff82c480124aac>] do_sysctl+0x1fc/0xa40
> (XEN)    [<ffff82c480213248>] syscall_enter+0xc8/0x122
> (XEN)
> (XEN) Pagetable walk from ffff82c48025cf70:
> (XEN)  L4[0x105] = 00000000cfcaa027 5555555555555555
> (XEN)  L3[0x112] = 00000000cfcab027 5555555555555555
> (XEN)  L2[0x001] = 000000022f27b063 5555555555555555
> (XEN)  L1[0x05c] = 00000000cfc5c262 5555555555555555
> (XEN)
> (XEN) ****************************************
> (XEN) Panic on CPU 0:
> (XEN) FATAL PAGE FAULT
> (XEN) [error_code=0010]
> (XEN) Faulting linear address: ffff82c48025cf70
> (XEN) ****************************************
>
>
> (XEN) Xen call trace:
> (XEN)    [<ffff82c48025d852>] notifier_chain_register+0x0/0x35
> (XEN)    [<ffff82c4801275b2>] alloc_trace_bufs+0x5cd/0x7a9
> (XEN)    [<ffff82c480127910>] tb_control+0x182/0x278
> (XEN)    [<ffff82c480124aec>] do_sysctl+0x1fc/0xa40
> (XEN)    [<ffff82c480213288>] syscall_enter+0xc8/0x122
> (XEN)
> (XEN) Pagetable walk from ffff82c48025d852:
> (XEN)  L4[0x105] = 00000000cfcaa027 5555555555555555
> (XEN)  L3[0x112] = 00000000cfcab027 5555555555555555
> (XEN)  L2[0x001] = 000000022f27b063 5555555555555555
> (XEN)  L1[0x05d] = 00000000cfc5d262 5555555555555555
> (XEN)
> (XEN) ****************************************
> (XEN) Panic on CPU 1:
> (XEN) FATAL PAGE FAULT
> (XEN) [error_code=0010]
> (XEN) Faulting linear address: ffff82c48025d852
> (XEN) ****************************************
>
>
> Signed-off-by: Christoph Egger<Christoph.Egger@amd.com>
>
>


-- 
---to satisfy European Law for business letters:
Advanced Micro Devices GmbH
Einsteinring 24, 85689 Dornach b. Muenchen
Geschaeftsfuehrer: Alberto Bozzo, Andrew Bowd
Sitz: Dornach, Gemeinde Aschheim, Landkreis Muenchen
Registergericht Muenchen, HRB Nr. 43632