Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932699AbXBVHkp (ORCPT ); Thu, 22 Feb 2007 02:40:45 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932730AbXBVHkp (ORCPT ); Thu, 22 Feb 2007 02:40:45 -0500 Received: from nf-out-0910.google.com ([64.233.182.190]:14012 "EHLO nf-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932699AbXBVHko (ORCPT ); Thu, 22 Feb 2007 02:40:44 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:date:from:to:cc:subject:message-id:references:mime-version:content-type:content-disposition:in-reply-to:user-agent:sender; b=agfMN20Dadtiy6uWOU4lMFUSGgPFyPxz3BxVE4GdMfb/F424IfKwTzhRtfZDzOeUy2tIKrTt7Z/K28/LID5YfZk3LLQEdNt5gGVF9rHqgY4r2900vQmFZqQXg0QHqfSq3h4RPb1/XeznpQ+x2qT40PxYcBb7m2sYTMCKP8u/riM= Date: Thu, 22 Feb 2007 07:39:30 +0000 From: Frederik Deweerdt To: "H. Peter Anvin" Cc: Jose Goncalves , akpm@linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: Serial related oops Message-ID: <20070222073930.GB4113@slug> References: <20070219143520.GB27370@flint.arm.linux.org.uk> <20070220144814.GJ566@slug> <20070219150508.GD27370@flint.arm.linux.org.uk> <45D9D073.7020701@inov.pt> <20070219164200.GF27370@flint.arm.linux.org.uk> <45D9E46C.4030408@inov.pt> <20070219212347.GA4258@flint.arm.linux.org.uk> <45DC537B.6020108@inov.pt> <20070221230503.GA28156@flint.arm.linux.org.uk> <45DD30DE.20503@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <45DD30DE.20503@zytor.com> User-Agent: mutt-ng/devel-r804 (Linux) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1265 Lines: 33 On Wed, Feb 21, 2007 at 09:57:50PM -0800, H. Peter Anvin wrote: > Russell King wrote: > > >Plainly, %ebx changed across the call to serial_in() at c01c0f7b. > >First thing to notice is this violates the C code - "up" can not > >change. > >Now let's look at serial_in: > >c01bfa70: 55 push %ebp > >c01bfa71: 89 e5 mov %esp,%ebp > >c01bfa73: 53 push %ebx > >... > >c01bfab7: 5b pop %ebx > >c01bfab8: 5d pop %ebp > >c01bfab9: c3 ret > >This code tells the CPU to preserves %ebx and %ebp. But we know %ebx > >_wasn't_ preserved. Ergo, your CPU is plainly not doing what the code > >told it to do. > > ... assuming nothing else clobbered the stack slot (which would be a compiler > error, or a wild pointer.) > > Got a disassembly of the whole function? > Jose posted it higher in the thread: http://lkml.org/lkml/2007/2/21/139 Regards, Frederik - 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/