Received: by oss.sgi.com id ; Thu, 11 May 2000 02:30:27 +0000 Received: from smtprch1.nortelnetworks.com ([192.135.215.14]:59383 "EHLO smtprch1.nortel.com") by oss.sgi.com with ESMTP id ; Thu, 11 May 2000 02:30:14 +0000 Received: from zsngd101.asiapac.nortel.com (actually znsgd101) by smtprch1.nortel.com; Wed, 10 May 2000 21:25:08 -0500 Received: from zctwb003.asiapac.nortel.com ([47.152.32.111]) by zsngd101.asiapac.nortel.com with SMTP (Microsoft Exchange Internet Mail Service Version 5.5.2650.21) id K192HCCM; Thu, 11 May 2000 10:24:58 +0800 Received: from pwold011.asiapac.nortel.com ([47.181.193.45]) by zctwb003.asiapac.nortel.com with SMTP (Microsoft Exchange Internet Mail Service Version 5.5.2650.21) id J8YN6Z9X; Thu, 11 May 2000 12:25:01 +1000 Received: from uow.edu.au (IDENT:akpm@localhost [127.0.0.1]) by pwold011.asiapac.nortel.com (8.9.3/8.9.3) with ESMTP id MAA05381; Thu, 11 May 2000 12:24:54 +1000 Message-ID: <391A19F6.5C72A6E0@uow.edu.au> Date: Thu, 11 May 2000 02:24:54 +0000 X-Sybari-Space: 00000000 00000000 00000000 From: Andrew Morton X-Mailer: Mozilla 4.61 [en] (X11; I; Linux 2.3.99-pre5 i686) X-Accept-Language: en MIME-Version: 1.0 To: kuznet@ms2.inr.ac.ru CC: netdev@oss.sgi.com Subject: Re: tx_timeout and timer serialisation References: <390EE5BB.2AF2F1CD@uow.edu.au> from "Andrew Morton" at May 3, 0 00:27:07 am <200005021549.TAA16319@ms2.inr.ac.ru> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-netdev@oss.sgi.com Precedence: bulk Return-Path: X-Orcpt: rfc822;netdev-outgoing kuznet@ms2.inr.ac.ru wrote: > > Hello! Hello indeed. I'm catching up on a week away... [ Regarding del_timer_sync() ] > Alas, it has fatal bug. Namely, timer handler _code_ can be released > in between timer_exit() and return from handler. It is utterly > unlikely, but the bug is fatal. 8) I do not know how to repair > this without refcounts. Why does the handler have to call timer_exit() at all? Could we not clear timer->running in run_timer_list()? That would certainly protect us from the problem you identify... -- -akpm-