Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752769AbYJYONi (ORCPT ); Sat, 25 Oct 2008 10:13:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752018AbYJYONa (ORCPT ); Sat, 25 Oct 2008 10:13:30 -0400 Received: from casper.infradead.org ([85.118.1.10]:40664 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751761AbYJYON3 (ORCPT ); Sat, 25 Oct 2008 10:13:29 -0400 Date: Sat, 25 Oct 2008 07:13:48 -0700 From: Arjan van de Ven To: Arjan van de Ven Cc: "Carlos R. Mafra" , linux-kernel@vger.kernel.org Subject: Re: [2.6.28-rc1 regression] wmifinfo dockapp takes 100% of cpu (bisected) Message-ID: <20081025071348.63c426d9@infradead.org> In-Reply-To: <490327B6.2090903@linux.intel.com> References: <20081025094043.GA4438@localhost.aei.mpg.de> <490327B6.2090903@linux.intel.com> Organization: Intel X-Mailer: Claws Mail 3.5.0 (GTK+ 2.12.12; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2167 Lines: 76 On Sat, 25 Oct 2008 07:05:42 -0700 Arjan van de Ven wrote: > Carlos R. Mafra wrote: > > > Hi, > > the line below is the key one: > > > select(4, [3], NULL, NULL, {0, 5000000}) = -1 EINVAL (Invalid > > argument) > > the application gives us an invalid timeval; it should have been (5, > 0) However, if the kernel accepted this before the kernel needs to > now also accept it obviously, I'll look into it This patch should fix it; I'm a bit worried that I need to fix up userlands "mess", but ok. I also checked all other converted functions, and only select has this problem. The problem is that the conversion from microseconds to nanoseconds is overflowing ;-( can you give this one a test? diff --git a/fs/compat.c b/fs/compat.c index fe3c9bf..95ceee6 100644 --- a/fs/compat.c +++ b/fs/compat.c @@ -1680,9 +1680,16 @@ asmlinkage long compat_sys_select(int n, compat_ulong_t __user *inp, int ret; if (tvp) { + int i; if (copy_from_user(&tv, tvp, sizeof(tv))) return -EFAULT; + while (tv.tv_usec > USEC_PER_SEC && i < 1000) { + i++; + tv.tv_sec ++; + tv.tv_usec -= USEC_PER_SEC; + } + to = &end_time; if (poll_select_set_timeout(to, tv.tv_sec, tv.tv_usec * NSEC_PER_USEC)) diff --git a/fs/select.c b/fs/select.c index 448e440..e4e7cdb 100644 --- a/fs/select.c +++ b/fs/select.c @@ -515,9 +515,16 @@ asmlinkage long sys_select(int n, fd_set __user *inp, fd_set __user *outp, int ret; if (tvp) { + int i = 0; if (copy_from_user(&tv, tvp, sizeof(tv))) return -EFAULT; + while (tv.tv_usec > USEC_PER_SEC && i < 1000) { + i++; + tv.tv_sec ++; + tv.tv_usec -= USEC_PER_SEC; + } + to = &end_time; if (poll_select_set_timeout(to, tv.tv_sec, tv.tv_usec * NSEC_PER_USEC)) -- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org -- 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/