Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965516Ab3E2JtD (ORCPT ); Wed, 29 May 2013 05:49:03 -0400 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]:40369 "EHLO cam-admin0.cambridge.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964948Ab3E2Js7 (ORCPT ); Wed, 29 May 2013 05:48:59 -0400 Date: Wed, 29 May 2013 10:48:27 +0100 From: Will Deacon To: richard -rw- weinberger Cc: "Wang, Yalin" , "linux-arch@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" Subject: Re: A bug about system call on ARM Message-ID: <20130529094826.GD13095@mudshark.cambridge.arm.com> References: <35FD53F367049845BC99AC72306C23D1610991B85B@CNBJMBX05.corpusers.net> <35FD53F367049845BC99AC72306C23D1610991B85D@CNBJMBX05.corpusers.net> <35FD53F367049845BC99AC72306C23D1610991B85E@CNBJMBX05.corpusers.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2132 Lines: 51 Hello, On Wed, May 29, 2013 at 09:46:42AM +0100, richard -rw- weinberger wrote: > On Wed, May 29, 2013 at 10:24 AM, Wang, Yalin wrote: > > I have download the latest linux kernel code 3.9.4 > > And Compare with 3.4.0 kernel . > > > > It seems there is no change for this part , > > So it will still happen . > > Does anyone know who is responsible for arm arch part kernel code ? > > See MAINTAINERS file. > CC'ing linux-arm-kernel@lists.infradead.org Cheers for adding us to CC. > >> #ifdef CONFIG_ARM_THUMB > >> tst r8, #PSR_T_BIT > >> movne r10, #0 @ no thumb OABI emulation > >> ldreq r10, [lr, #-4] @ get SWI instruction // crash at this instruction, when get SWI instruction Do you have the panic log please? Also, which SoC are you using and how are you reproducing this? > >> ldr r10, [lr, #-4] @ get SWI instruction > >> A710( and ip, r10, #0x0f000000 @ check for SWI ) > >> A710( teq ip, #0x0f000000 ) > >> A710( bne .Larm710bug ) > >> #endif > >> #ifdef CONFIG_CPU_ENDIAN_BE8 > >> rev r10, r10 @ little endian instruction > >> #endif > >> > >> /********************************************************************* > >> ******************************/ > >> > >> Then reason why it will crash when get SWI instruction is maybe This > >> page is clear to aged by kernel, But this MMU fault happpened in > >> kernel, So the kernel do_page_fault function will not clear this page > >> to young, So that will crash . Sounds like we might need some USER annotations around the instruction loads, but we should also rework the code so that we re-enable interrupts first. Will -- 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/