Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161732AbWKHWIf (ORCPT ); Wed, 8 Nov 2006 17:08:35 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1161731AbWKHWIf (ORCPT ); Wed, 8 Nov 2006 17:08:35 -0500 Received: from smtp.osdl.org ([65.172.181.4]:52886 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1161726AbWKHWId (ORCPT ); Wed, 8 Nov 2006 17:08:33 -0500 Date: Wed, 8 Nov 2006 14:03:07 -0800 From: Andrew Morton To: Eric Dumazet Cc: Evgeniy Polyakov , David Miller , Ulrich Drepper , netdev , Zach Brown , Christoph Hellwig , Chase Venters , Johann Borck , linux-kernel@vger.kernel.org, Jeff Garzik , Davide Libenzi Subject: Re: [take23 0/5] kevent: Generic event handling mechanism. Message-Id: <20061108140307.da7d815f.akpm@osdl.org> In-Reply-To: <200611081551.14671.dada1@cosmosbay.com> References: <1154985aa0591036@2ka.mipt.ru> <20061107141718.f7414b31.akpm@osdl.org> <20061108082147.GA2447@2ka.mipt.ru> <200611081551.14671.dada1@cosmosbay.com> X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.6; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1482 Lines: 44 On Wed, 8 Nov 2006 15:51:13 +0100 Eric Dumazet wrote: > [PATCH] eventpoll : In case a fault occurs during copy_to_user(), we should > report the count of events that were successfully copied into user space, > instead of EFAULT. That would be consistent with behavior of read/write() > syscalls for example. > > Signed-off-by: Eric Dumazet > > > > [eventpoll.patch text/plain (424B)] > --- linux/fs/eventpoll.c 2006-11-08 15:37:36.000000000 +0100 > +++ linux/fs/eventpoll.c 2006-11-08 15:38:31.000000000 +0100 > @@ -1447,7 +1447,7 @@ > &events[eventcnt].events) || > __put_user(epi->event.data, > &events[eventcnt].data)) > - return -EFAULT; > + return eventcnt ? eventcnt : -EFAULT; > if (epi->event.events & EPOLLONESHOT) > epi->event.events &= EP_PRIVATE_BITS; > eventcnt++; > Definitely a better interface, but I wonder if it's too late to change it. An app which does if (epoll_wait(...) == -1) barf(errno); else assume_all_events_were_received(); will now do the wrong thing. otoh, such an applciation basically _has_ to use the epoll_wait() return value to work out how many events it received, so maybe it's OK... - 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/