From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with SMTP id AF3B96B01EE for ; Tue, 27 Apr 2010 18:56:03 -0400 (EDT) Message-ID: <4BD76B81.2070606@tauceti.net> Date: Wed, 28 Apr 2010 00:56:01 +0200 From: Robert Wimmer MIME-Version: 1.0 Subject: Re: [Bugme-new] [Bug 15709] New: swapper page allocation failure References: <4BC43097.3060000@tauceti.net> <4BCC52B9.8070200@tauceti.net> <20100419131718.GB16918@redhat.com> <20100421094249.GC30855@redhat.com> <20100422100304.GC30532@redhat.com> <4BD12F9C.30802@tauceti.net> <20100425091759.GA9993@redhat.com> <4BD4A917.70702@tauceti.net> <20100425204916.GA12686@redhat.com> <1272284154.4252.34.camel@localhost.localdomain> <4BD5F6C5.8080605@tauceti.net> <1272315854.8984.125.camel@localhost.localdomain> <4BD61147.40709@tauceti.net> <1272324536.16814.45.camel@localhost.localdomain> In-Reply-To: <1272324536.16814.45.camel@localhost.localdomain> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Trond Myklebust Cc: "Michael S. Tsirkin" , Avi Kivity , Andrew Morton , linux-mm@kvack.org, bugzilla-daemon@bugzilla.kernel.org, Rusty Russell , Mel Gorman , linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org List-ID: I've applied the patch against the kernel which I got from "git clone ...." resulted in a kernel 2.6.34-rc5. The stack trace after mounting NFS is here: https://bugzilla.kernel.org/attachment.cgi?id=26166 /var/log/messages after soft lockup: https://bugzilla.kernel.org/attachment.cgi?id=26167 I hope that there is any usefull information in there. Thanks! Robert On 04/27/10 01:28, Trond Myklebust wrote: > On Tue, 2010-04-27 at 00:18 +0200, Robert Wimmer wrote: > >>> Sure. In addition to what you did above, please do >>> >>> mount -t debugfs none /sys/kernel/debug >>> >>> and then cat the contents of the pseudofile at >>> >>> /sys/kernel/debug/tracing/stack_trace >>> >>> Please do this more or less immediately after you've finished mounting >>> the NFSv4 client. >>> >>> >> I've uploaded the stack trace. It was generated >> directly after mounting. Here are the stacks: >> >> After mounting: >> https://bugzilla.kernel.org/attachment.cgi?id=26153 >> After the soft lockup: >> https://bugzilla.kernel.org/attachment.cgi?id=26154 >> The dmesg output of the soft lockup: >> https://bugzilla.kernel.org/attachment.cgi?id=26155 >> >> >>> Does your server have the 'crossmnt' or 'nohide' flags set, or does it >>> use the 'refer' export option anywhere? If so, then we might have to >>> test further, since those may trigger the NFSv4 submount feature. >>> >>> >> The server has the following settings: >> rw,nohide,insecure,async,no_subtree_check,no_root_squash >> >> Thanks! >> Robert >> >> >> > That second trace is more than 5.5K deep, more than half of which is > socket overhead :-(((. > > The process stack does not appear to have overflowed, however that trace > doesn't include any IRQ stack overhead. > > OK... So what happens if we get rid of half of that trace by forcing > asynchronous tasks such as this to run entirely in rpciod instead of > first trying to run in the process context? > > See the attachment... > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org