From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.33) id 1ClqTp-0004ox-P8 for qemu-devel@nongnu.org; Tue, 04 Jan 2005 10:20:17 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.33) id 1ClqTo-0004oB-4s for qemu-devel@nongnu.org; Tue, 04 Jan 2005 10:20:17 -0500 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.33) id 1ClqTn-0004o8-VV for qemu-devel@nongnu.org; Tue, 04 Jan 2005 10:20:15 -0500 Received: from [80.91.229.2] (helo=main.gmane.org) by monty-python.gnu.org with esmtp (Exim 4.34) id 1ClqI1-00055V-Df for qemu-devel@nongnu.org; Tue, 04 Jan 2005 10:08:05 -0500 Received: from list by main.gmane.org with local (Exim 3.35 #1 (Debian)) id 1Clq6Z-0003V2-00 for ; Tue, 04 Jan 2005 15:56:15 +0100 Received: from inet.ycc.ru ([217.148.52.177]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Tue, 04 Jan 2005 15:56:14 +0100 Received: from patrakov by inet.ycc.ru with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Tue, 04 Jan 2005 15:56:14 +0100 From: "Alexander E. Patrakov" Date: Tue, 04 Jan 2005 19:55:46 +0500 Message-ID: References: <2ad73a0501040635d2dc2c3@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=koi8-r Content-Transfer-Encoding: 8Bit Sender: news Subject: [Qemu-devel] Re: Something is probably wrong with "int 3" Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Andr? Braga wrote: > On Tue, 04 Jan 2005 18:09:32 +0500, Alexander E. Patrakov > wrote: >> clearly state that the fault is at the "int 3" instruction, not at "ret". >> Can anyone explain this difference? Is this a bug in qemu? > > Uh... INT 3 is the debugger services interrupt. It usually triggers a > resident debugger so it attaches to the calling process. Yes, in this case DrWatson pops up. > It might be that Firefox reached a situation where it knew it would > crash, so it called the debugger first and then failed returning to an > invalid address (maybe the stack was corrupt?) Look at the crash dump - the DbgBreakPoint() is called from kernel32!SetThreadExecutionState, i.e. from deep inside the Windows kernel. Firefox just happens to be an easy way to trigger this. And yes, the error that causes Firefox to crash is actually before this. Consider my first mail in this thread as additional bug report, unrelated to Firefox in any way. I know that fixing "wrong fault address after int 3" will not cure Firefox, but it's a bug anyway, if I understand that correctly. > Anyway, I don't think that QEMU handles INT 3 at all; the fault must > be somewhere else. Are you absolutely sure your Firefox build isn't > calling MMX/SSE instructions? Is it a contributed build or is it > official? It is the official build, and it runs perfectly on old i586 machines. -- Alexander E. Patrakov