From mboxrd@z Thu Jan 1 00:00:00 1970 From: Richard Weinberger Subject: Re: [PATCH][Resend v2] Fix infinite loop in search_binary_handler() Date: Tue, 5 Jul 2011 00:17:29 +0200 Message-ID: <201107050017.30365.richard@nod.at> References: <1309779003-8668-1-git-send-email-richard@nod.at> <201107041707.23165.richard@nod.at> <201107050703.EGJ13561.OFQHOOVMJtLFSF@I-love.SAKURA.ne.jp> Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Cc: viro@zeniv.linux.org.uk, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org To: Tetsuo Handa Return-path: In-Reply-To: <201107050703.EGJ13561.OFQHOOVMJtLFSF@I-love.SAKURA.ne.jp> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org Am Dienstag 05 Juli 2011, 00:03:47 schrieb Tetsuo Handa: > Richard Weinberger wrote: > > Am Montag 04 Juli 2011, 16:59:32 schrieb Richard Weinberger: > > > Here the second boot log: > > > http://userweb.kernel.org/~rw/boot2.log > > > > > > The interesting part is: > > > ---cut--- > > > VFS: Mounted root (ext2 filesystem) readonly on device 98:0. > > > Calling request_module() swapper 1 /sbin/init 1 3 > > > Calling request_module() kworker/u:0 211 /sbin/modprobe 4 3 > > > ... > > > Calling request_module() kworker/u:0 8741 /sbin/modprobe 4 3 > > > ---cut--- > > > > > > After the last "Calling request_module..." message no more messages > > > appear and the kernel seems to loop for ever. > > > > Please ignore this. > > The "Calling request_module..." messages continue for ever. > > In the first case my terminal locked up... > > current->pid also wraps around. > > Please note that the each PID is printed for twice. > This means that each thread within the loop tries to create a thread. > Therefore, it will repeat for (1 << MAX_KMOD_CONCURRENT) times. > It is large enough to wrap the PID. > Well, try with smaller MAX_KMOD_CONCURRENT (e.g. 3). > With MAX_KMOD_CONCURRENT=3 it takes only a few seconds until the modprobe storm ends. How shall we proceed? Applying my ad-hoc patch or lowering MAX_KMOD_CONCURRENT? Thanks, //richard