Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933587AbaDIOVm (ORCPT ); Wed, 9 Apr 2014 10:21:42 -0400 Received: from nat28.tlf.novell.com ([130.57.49.28]:37296 "EHLO nat28.tlf.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932866AbaDIOVl convert rfc822-to-8bit (ORCPT ); Wed, 9 Apr 2014 10:21:41 -0400 Message-Id: <5345739202000078000073EA@nat28.tlf.novell.com> X-Mailer: Novell GroupWise Internet Agent 14.0.0 Date: Wed, 09 Apr 2014 15:21:38 +0100 From: "Jan Beulich" To: Cc: , , , , Subject: Re: [Xen-devel] [PATCH] x86/xen: Fix 32-bit PV guests's usage of kernel_stack References: <1397052401-20220-1-git-send-email-boris.ostrovsky@oracle.com> In-Reply-To: <1397052401-20220-1-git-send-email-boris.ostrovsky@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>> On 09.04.14 at 16:06, wrote: > --- a/arch/x86/xen/xen-asm_32.S > +++ b/arch/x86/xen/xen-asm_32.S > @@ -88,7 +88,11 @@ ENTRY(xen_iret) > * avoid having to reload %fs > */ > #ifdef CONFIG_SMP > + pushw %fs > + movl $(__KERNEL_PERCPU), %eax > + movl %eax, %fs > GET_THREAD_INFO(%eax) > + popw %fs I don't think it's guaranteed that this can't fault. Jan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/