Re: Local DoS through write heavy I/O on CFQ & Deadline

Alex Bligh
2012-10-12T12:57:57Z

Alan,

--On 11 October 2012 14:46:34 +0100 Alan Cox <alan@lxorguk.ukuu.org.uk>
wrote:

>> We have reproduced this on multiple hardware environments, using 3.2
>> (/proc/version_signature gives "Ubuntu 3.2.0-29.46-generic 3.2.24").
>> Anecdotally we believe the situation has worsened since 3.0.
>
> I've certainly seen this on 3.0 and 3.2, but do you still see it on
> 3.5/6 ?

We've just tested this. We see exactly the same issue on 3.6.1 using
the current build of the Ubuntu Quantal kernel, which is:

Linux version 3.6.1-030601-generic (apw@gomeisa) (gcc version 4.6.3
(Ubuntu/Linaro 4.6.3-1ubuntu5) ) #201210071322 SMP Sun Oct 7 17:23:28 UTC
2012

More details (including full logs for that kernel) at:

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1064521

--
Alex Bligh