linux-kernel - Re: + shmem-fix-faulting-into-a-hole-while-its-punched-take-2.patch added to -mm tree

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] [thread-next>] [day] [month] [year] [list]

Message-ID: <53BED7F6.4090502@oracle.com>
Date:	Thu, 10 Jul 2014 14:14:14 -0400
From:	Sasha Levin <sasha.levin@...cle.com>
To:	Hugh Dickins <hughd@...gle.com>
CC:	Heiko Carstens <heiko.carstens@...ibm.com>,
	Vlastimil Babka <vbabka@...e.cz>, akpm@...ux-foundation.org,
	davej@...hat.com, koct9i@...il.com, lczerner@...hat.com,
	stable@...r.kernel.org, "linux-mm@...ck.org" <linux-mm@...ck.org>,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: + shmem-fix-faulting-into-a-hole-while-its-punched-take-2.patch
 added to -mm tree

On 07/10/2014 01:55 PM, Hugh Dickins wrote:
>> And finally, (not) holding the i_mmap_mutex:
> I don't understand what prompts you to show this particular task.
> I imagine the dump shows lots of other tasks which are waiting to get an
> i_mmap_mutex, and quite a lot of other tasks which are neither waiting
> for nor holding an i_mmap_mutex.
> 
> Why are you showing this one in particular?  Because it looks like the
> one you fingered yesterday?  But I didn't see a good reason to finger
> that one either.

There are a few more tasks like this one, my criteria was tasks that lockdep
claims were holding i_mmap_mutex, but are actually not.

One new thing that I did notice is that since trinity spins a lot of new children
to test out things like execve() which would kill said children, there tends to
be a rather large amount of new tasks created and killed constantly.

So if you look at the bottom of the new log (attached), you'll see that there
are quite a few "trinity-subchild" processes trying to die, unsuccessfully.

Thanks,
Sasha

Download attachment "log.gz" of type "application/gzip" (354861 bytes)