From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751805AbdJCN3S (ORCPT ); Tue, 3 Oct 2017 09:29:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42102 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751171AbdJCN3R (ORCPT ); Tue, 3 Oct 2017 09:29:17 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com CDA61C059B6B Authentication-Results: ext-mx08.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx08.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=jpoimboe@redhat.com Date: Tue, 3 Oct 2017 08:29:15 -0500 From: Josh Poimboeuf To: Borislav Petkov Cc: Tetsuo Handa , tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org Subject: Re: [4.14-rc1 x86] WARNING: kernel stack regs at f60bbb12 in swapper:1 has bad 'bp' value 0ba00000 Message-ID: <20171003132915.poy7sv73eev6to7m@treble> References: <201709082206.JCD12980.FSQOFHMFOOtVJL@I-love.SAKURA.ne.jp> <201709142006.GJE87018.QSFJMHOVLOFtOF@I-love.SAKURA.ne.jp> <201709221335.EDE64522.JSHFFMLFOVOOtQ@I-love.SAKURA.ne.jp> <201710031929.GGI78159.FHLQOJOtFMVSOF@I-love.SAKURA.ne.jp> <20171003103744.hxnz7o73rxzj63gx@pd.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20171003103744.hxnz7o73rxzj63gx@pd.tnic> User-Agent: Mutt/1.6.0.1 (2016-04-01) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Tue, 03 Oct 2017 13:29:17 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Oct 03, 2017 at 12:37:44PM +0200, Borislav Petkov wrote: > On Tue, Oct 03, 2017 at 07:29:36PM +0900, Tetsuo Handa wrote: > > Tetsuo Handa wrote: > > > Tetsuo Handa wrote: > > > > Tetsuo Handa wrote: > > > > > I'm seeing below error between > > > > > 4898b99c261efe32 ("Merge tag 'acpi-4.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm") (git bisect good (presumably)) > > > > > e6f3faa734a00c60 ("locking/lockdep: Fix workqueue crossrelease annotation") (git bisect bad) on linux.git . > > > > > > > > F.Y.I. This error remains as of 46c1e79fee417f15 ("Merge branch 'perf-urgent-for-linus' of > > > > git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip") on linux.git . > > > > > > > > > > This error still remains as of 6e80ecdddf4ea6f3 ("Merge branch 'libnvdimm-fixes' > > > of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm") on linux.git . > > > > > > I'm suspecting that this error is causing very unstable x86_32 kernel. > > > It seems that this error occurs (though rare frequency) even on x86_64 kernel. > > > > > > Nobody cares? > > > > > 4.14-rc3 still trivially panics due to this error. Is this problem known? Can you try with the following patch? It should hopefully give more useful information in the dump. diff --git a/arch/x86/kernel/unwind_frame.c b/arch/x86/kernel/unwind_frame.c index d145a0b1f529..191012762aa0 100644 --- a/arch/x86/kernel/unwind_frame.c +++ b/arch/x86/kernel/unwind_frame.c @@ -44,7 +44,8 @@ static void unwind_dump(struct unwind_state *state) state->stack_info.type, state->stack_info.next_sp, state->stack_mask, state->graph_idx); - for (sp = state->orig_sp; sp; sp = PTR_ALIGN(stack_info.next_sp, sizeof(long))) { + for (sp = PTR_ALIGN(state->orig_sp, sizeof(long)); sp; + sp = PTR_ALIGN(stack_info.next_sp, sizeof(long))) { if (get_stack_info(sp, state->task, &stack_info, &visit_mask)) break; @@ -178,7 +179,7 @@ static struct pt_regs *decode_frame_pointer(unsigned long *bp) { unsigned long regs = (unsigned long)bp; - if (!(regs & 0x1)) + if ((regs & (sizeof(long)-1)) != 1) return NULL; return (struct pt_regs *)(regs & ~0x1); @@ -221,6 +222,10 @@ static bool update_stack_state(struct unwind_state *state, &state->stack_mask)) return false; + /* Make sure the frame pointer is properly aligned: */ + if ((unsigned long)frame & (sizeof(long)-1)) + return false; + /* Make sure it only unwinds up and doesn't overlap the prev frame: */ if (state->orig_sp && state->stack_info.type == prev_type && frame < prev_frame_end)