Re: [dm-devel] Page Allocation Failures/OOM with dm-crypt on software RAID10 (Intel Rapid Storage)

From: Ondrej Kozina
Date: Wed Jul 13 2016 - 12:25:12 EST


On 07/13/2016 05:32 PM, Matthias Dahl wrote:

No matter what, I have no clue how to further diagnose this issue. And
given that I already had unsolvable issues with dm-crypt a couple of
months ago with my old machine where the system simply hang itself or
went OOM when the swap was encrypted and just a few kilobytes needed to
be swapped out, I am not so sure anymore I can trust dm-crypt with a
full disk encryption to the point where I feel "safe"... as-in, nothing
bad will happen or the system won't suddenly hang itself due to it. Or
if a bug is introduced, that it will actually be possible to diagnose it
and help fix it or that it will even be eventually fixed. Which is
really
a pity, since I would really have liked to help solve this. With the
swap issue, I did git bisects, tests, narrowed it down to kernel
versions
when said bug was introduced... but in the end, the bug is still present
as far as I know. :(


One step after another. Mathias, your original report was not forgotten, it's just not so easy to find the real culprit and fix it without causing yet another regression. See the https://marc.info/?l=linux-mm&m=146825178722612&w=2 thread...

Not to mention that on current 4.7-rc7 kernels it behaves yet slightly differently (yet far from ideally).

Regards O.