Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751028AbWHaHsO (ORCPT ); Thu, 31 Aug 2006 03:48:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751218AbWHaHsO (ORCPT ); Thu, 31 Aug 2006 03:48:14 -0400 Received: from gwmail.nue.novell.com ([195.135.221.19]:10425 "EHLO emea5-mh.id5.novell.com") by vger.kernel.org with ESMTP id S1751028AbWHaHsO (ORCPT ); Thu, 31 Aug 2006 03:48:14 -0400 Message-Id: <44F6B082.76E4.0078.0@novell.com> X-Mailer: Novell GroupWise Internet Agent 7.0.1 Date: Thu, 31 Aug 2006 09:48:50 +0200 From: "Jan Beulich" To: "Andi Kleen" Cc: "J. Bruce Fields" , "Badari Pulavarty" , , , "lkml" Subject: Re: Was: boot failure, "DWARF2 unwinder stuck at 0xc0100199" References: <20060820013121.GA18401@fieldses.org> <1156974410.16136.1.camel@dyn9047017100.beaverton.ibm.com> <44F6AD47.76E4.0078.0@novell.com> <200608310941.40076.ak@suse.de> In-Reply-To: <200608310941.40076.ak@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1192 Lines: 31 >>> Andi Kleen 31.08.06 09:41 >>> >On Thursday 31 August 2006 09:35, Jan Beulich wrote: >> Andi submitted a fix for this to Linus, but that's post-rc5. Jan > >I assume you mean the fallback validation fix. Linus unfortunately >didn't merge any of my new patches yet :/ Actually, the same patch, but other pieces of it ... >But did you ever work out why the stack backtrace completely restarted? >I never got this. In theory the RSP gotten out of the unwind >context and used for the fallback should have been already near the end >and the old unwinder shouldn't have found much. In the old (up to -rc5) code, we had if (unw_ret > 0 && !arch_unw_user_mode(&info)) { < all the fallback handling> } with no else, thus just falling through (without even changing the stack pointer, which was wrong when unw_ret > 0 but we reached a user mode address (i.e. as in the example here, after unwinding out of a syscall frame). 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/