[dm-devel] hunt for 2.6.37 dm-crypt+ext4 corruption? (was: Re: dm-crypt barrier support is effective)

[Jon Nelson]

On Thu, Dec 9, 2010 at 2:13 PM, Ted Ts'o <tytso at mit.edu> wrote:
> On Thu, Dec 09, 2010 at 12:10:58PM -0600, Jon Nelson wrote:
>>
>> You should be OK, there. Are you using encryption or no?
>> I had difficulty replicating the issue without encryption.
>
> Yes, I'm using encryption.  LUKS with aes-xts-plain-sha256, and then
> LVM on top of LUKS.

Hmm.
The cipher is listed as:
aes-cbc-essiv:sha256

>> > If you can point out how to query pgsql_tmp (I'm using a completely
>> > default postgres install), that would be helpful, but I don't think it
>> > would be going anywhere else.
>>
>> Normally it's /var/lib/pgsql/data/pgsql_tmp (or
>> /var/lib/postgres/data/pgsql_tmp in your case). By placing
>> /var/lib/{postgresql,pgsql}/data on the LUKS + ext4 volume, on both
>> openSUSE 11.3 and Kubuntu, I was able to replicate the problem easily,
>> in VirtualBox. I can give qemu a try. In both cases I was using a
>> 2.6.37x kernel.
>
> Ah, I'm not using virtualization.  I'm running on a X410 laptop, on
> raw hardware.  Perhaps virtualization slows things down enough that it
> triggers?  Or maybe you're running with a more constrained memory than
> I?  How much memory do you have configured in your VM?

512MB.

'free' reports 75MB, 419MB free.

I originally noticed the problem on really real hardware (thinkpad
T61p), however.

-- 
Jon