Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030515AbWHUQoV (ORCPT ); Mon, 21 Aug 2006 12:44:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964990AbWHUQoU (ORCPT ); Mon, 21 Aug 2006 12:44:20 -0400 Received: from xenotime.net ([66.160.160.81]:33743 "HELO xenotime.net") by vger.kernel.org with SMTP id S964987AbWHUQoU (ORCPT ); Mon, 21 Aug 2006 12:44:20 -0400 Date: Mon, 21 Aug 2006 09:47:18 -0700 From: "Randy.Dunlap" To: "Jan Beulich" Cc: "J. Bruce Fields" , "Andi Kleen" , Subject: Re: boot failure, "DWARF2 unwinder stuck at 0xc0100199" Message-Id: <20060821094718.79c9a31a.rdunlap@xenotime.net> In-Reply-To: <44E97353.76E4.0078.0@novell.com> References: <20060820013121.GA18401@fieldses.org> <44E97353.76E4.0078.0@novell.com> Organization: YPO4 X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.10; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2167 Lines: 60 On Mon, 21 Aug 2006 08:48:19 +0200 Jan Beulich wrote: > >>> "J. Bruce Fields" 20.08.06 03:31 >>> > >As of 2.6.18-rc3, one of my test machines stopped booting. I'm not > >seeing the whole OOPS (I could probably set up a serial console if > >necessary), but it ends in something like: > > > >trace_hardirqs_on > >idesci_pc_intr > >ide_intr > >handle_IRQ_event > >__do_IRQ > >do_IRQ > >common_interrupt > >default_idle > >apm_cpu_idle > >cpu_idle > >rest_init > >start_kernel > >0xc0100199 > >DWARF2 unwinder stuck at 0xc0100199 > >Leftover inexact backtrace: > > ======================= > > BUG: unable to handle kernel paging request at virtual address 0000b034 > > printing eip: > >c0103712 > >*pde = 00000000 > >Recursive die() failure, output suppressed > > <0>Kernel panic - not syncing: Fatal exception in interrupt > > > >Bisecting, it looks like this starts happening after c97d20a..., > >"[PATCH] i386: Do backtrace fallback too", though it's a little tricky > >since the compile is broken near there for a little while. > > > >Kernel config appended; let me know if anything else would be useful. > > The 'stuck' unwinder issue at hand already has a fix, though planned to > be merged for 2.6.19 only. The crash after switching to the legacy > stack trace code is bad, though, but has little to do with the unwinder > additions/changes. The way that code reads the stack is just > inappropriate in contexts where things must be expected to be broken. "merged for 2.6.19" meaning: - in (before) 2.6.19, or - after 2.6.19 is released If "after," then it will likely need to be added to -stable also, so it might as well go in "before" 2.6.19 is released. > Finally, there is no visible correlation between the original problem (in > or from trace_hardirqs_on) and the unwinder - once that problem is > fixed, you're not likely to see the recursive die failure anymore either. --- ~Randy - 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/