From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755164Ab1ATVZz (ORCPT ); Thu, 20 Jan 2011 16:25:55 -0500 Received: from mail-wy0-f174.google.com ([74.125.82.174]:34132 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754885Ab1ATVZx (ORCPT ); Thu, 20 Jan 2011 16:25:53 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:cc:in-reply-to:references:content-type:date :message-id:mime-version:x-mailer:content-transfer-encoding; b=etZODRGGUn5FJFpSJ/42rRUSufbbJJhDd2tY3HjSkPX8DrxrXkwPVYwfmkP7mfOZRy KL96Ocqc6p/u0t8n0gu1JReeJbk9U6BaV7OnHXX0IztMf17hzPYCRWVCShLG4ET3vn8F a8N98tIG0dUT502V5CRA9AyUFbzzkW4qjD+5U= Subject: Re: [GIT] Networking From: Eric Dumazet To: Linus Torvalds Cc: David Miller , akpm@linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org In-Reply-To: References: <20110119.180418.216749267.davem@davemloft.net> Content-Type: text/plain; charset="UTF-8" Date: Thu, 20 Jan 2011 22:25:48 +0100 Message-ID: <1295558748.2613.28.camel@edumazet-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le jeudi 20 janvier 2011 à 13:12 -0800, Linus Torvalds a écrit : > On Wed, Jan 19, 2011 at 6:04 PM, David Miller wrote: > > > > 1) Revert a netlink flag sanity check that is causing regressions in > > existing applications. > ... > > This is a long-shot, but I thought I'd ask before I start trying to > bisect the fourth independent suspend/resume related issue in this > merge window.. > > When I suspend/resume while logged in by closing the lid on my laptop > on FC14, it causes the gnome-screensaver-dialog to start up. So far so > fine, that's what I want, and it all works fin in 2.6.37. > > But in current -git (and in -rc8, so it's not changed by your latest > pull request), gnome-screensaver-dialog gets stuck after I type in my > password, making the box basically useless. > > So I straced it over the network, and if I attach _when_ it is already > stuck, it immediately becomes unstuck. But if I attach to it before > typing my password, I can see the hang in strace, and it looks like > this: > > ... > read(3, 0x9806500, 4096) = -1 EAGAIN (Resource > temporarily unavailable) > poll([{fd=4, events=POLLIN}, {fd=3, events=POLLIN}, {fd=12, > events=POLLIN|POLLPRI}, {fd=14, events=POLLIN|POLLPRI}, {fd=9, > events=POLLIN|POLLPRI}, {fd=10, events=POLLIN|POLLPRI}, {fd=15, > events=POLLIN}, {fd=16, events=POLLIN}, {fd=17, events=0}, {fd=19, > events=POLLIN}], 10, -1) = ? ERESTART_RESTARTBLOCK (To be restarted) > restart_syscall( > > and that's it - it's now hung. So why did it work when I straced it > while hung? And why is it doing that ERESTART_RESTARTBLOCK in the > first place, I'm not seeing any signals there? > > So I tried sending it a useless signal, which will re-animate the > strace, and now I get: > > restart_syscall(<... resuming interrupted call ...>) = 1 > --- SIGWINCH (Window changed) @ 0 (0) --- > poll([{fd=3, events=POLLIN|POLLOUT}], 1, -1) = 1 ([{fd=3, revents=POLLOUT}]) > > Whee. That signal got it started again, and the poll finished immediately. > > And how/why did the input to the poll apparently change? That looks > suspicious too. Might be some odd strace artifact, but whatever. > > So I'm contacting you because that fd=3 is a socket (I didn't check > details), and because anything I find in the git logs that discusses > "poll" seems to be network-related. So I'm wondering it this rings any > bells, because bisecting this is going to be painful as hell (since I > have to carefully work around all the _other_ problems I've bisected > on that machine while doing so). > Do you know the type of socket ? UNIX or INET ? You could try a revert of 2c6607c611cb7bf0a6750bcea3 (net: add POLLPRI to sock_def_readable()) But I dont understand how it could hurt...