lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <462C4F94.7090107@sw.ru>
Date:	Mon, 23 Apr 2007 10:17:56 +0400
From:	Pavel Emelianov <xemul@...ru>
To:	Andrew Morton <akpm@...ux-foundation.org>
CC:	sct@...hat.com, linux-ext4@...r.kernel.org,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	devel@...nvz.org
Subject: Re: [PATCH] Check for error returned by kthread_create on creating
 journal thread

Andrew Morton wrote:
> On Mon, 16 Apr 2007 11:41:14 +0400
> Pavel Emelianov <xemul@...ru> wrote:
> 
>> If the thread failed to create the subsequent wait_event
>> will hang forever.
>>
>> This is likely to happen if kernel hits max_threads limit.
>>
>> Will be critical for virtualization systems that limit the
>> number of tasks and kernel memory usage within the container.
>>
>>
>> [diff-jbd-check-start-journal-thread-return-value  text/plain (1.7KB)]
>> --- ./fs/jbd/journal.c.jbdthreads	2007-04-16 11:17:36.000000000 +0400
>> +++ ./fs/jbd/journal.c	2007-04-16 11:30:09.000000000 +0400
>> @@ -211,10 +211,16 @@ end_loop:
>>  	return 0;
>>  }
>>  
>> -static void journal_start_thread(journal_t *journal)
>> +static int journal_start_thread(journal_t *journal)
>>  {
>> -	kthread_run(kjournald, journal, "kjournald");
>> +	struct task_struct *t;
>> +
>> +	t = kthread_run(kjournald, journal, "kjournald");
>> +	if (IS_ERR(t))
>> +		return PTR_ERR(t);
>> +
>>  	wait_event(journal->j_wait_done_commit, journal->j_task != 0);
>> +	return 0;
>>  }
> 
> Thanks.   Please don't forget those Signed-off-by:s

I will :)

> I assume that you runtime tested this and that the mount failed in
> an appropriate fashion?
> 

Yes. This was easy to test as we can force kthread_run() to fail
at the moment we want with the help of the beancounters ;)

Moreover this patch lives in our tree for a year or so in both
stable and development branches.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ