From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752924AbbCJRwH (ORCPT ); Tue, 10 Mar 2015 13:52:07 -0400 Received: from smtp43.i.mail.ru ([94.100.177.103]:33854 "EHLO smtp43.i.mail.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751882AbbCJRwE (ORCPT ); Tue, 10 Mar 2015 13:52:04 -0400 X-Greylist: delayed 1461 seconds by postgrey-1.27 at vger.kernel.org; Tue, 10 Mar 2015 13:52:03 EDT Message-ID: <54FF2F3E.7050503@list.ru> Date: Tue, 10 Mar 2015 20:51:58 +0300 From: Stas Sergeev User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 MIME-Version: 1.0 To: Peter Hurley , Andrew Morton CC: Linux kernel , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] n_tty: use kmalloc() instead of vmalloc() to avoid crash on armada-xp References: <54FF21BE.2040506@list.ru> <54FF2B45.8060407@hurleysoftware.com> In-Reply-To: <54FF2B45.8060407@hurleysoftware.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Spam: Not detected X-Mras: Ok Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 10.03.2015 20:35, Peter Hurley пишет: > On 03/10/2015 12:54 PM, Stas Sergeev wrote: >> Hello, the patch below is needed for a successful boot on armada-xp. >> >> >> -=-=-=-=-=-=-=-=-=# Don't remove this line #=-=-=-=-=-=-=-=-=- >> This fixes the following crash at boot: >> >> Unhandled fault: external abort on non-linefetch (0x808) at 0xf00ca018 >> Internal error: : 808 [#1] SMP ARM >> >> CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.0.0-rc1 #3 >> Hardware name: Marvell Armada 370/XP (Device Tree) >> task: ed41e800 ti: ed43e000 task.ti: ed43e000 >> PC is at _set_bit+0x28/0x50 >> LR is at n_tty_set_termios+0x328/0x358 >> pc : [] lr : [] psr: 40000113 >> sp : ed43fd00 ip : 00000000 fp : 00000000 >> r10: 00000002 r9 : 00000000 r8 : ec930200 >> r7 : 00000000 r6 : f00ca018 r5 : f00ca000 r4 : ed69cc00 >> r3 : 00002000 r2 : 00002000 r1 : f00ca018 r0 : 00000000 >> Flags: nZcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel >> Control: 10c5387d Table: 0000406a DAC: 00000015 >> Process swapper/0 (pid: 1, stack limit = 0xed43e220) >> >> The offending instruction in _set_bit() is "strex r0, r2, [r1]" >> For some reason the exclusive access instructions do not like the >> vmalloc() space... While there may be another fix to make them >> fine about vmalloc() space, it still looks like a good idea to >> use kmalloc() for allocating a small (sub-page) struct. > NAK. > > struct n_tty_data is order 2, not sub-page. OK, you are right, sorry. 8844 bytes. Is this really a target for vmalloc() though? I thought kmalloc() is preferable even for that size. > The abort means something else is wrong; that's what needs > tracking down and fixing. Yeah, I even mentioned that in a commit log.