Re: [PATCH] parisc: mm: Fix a memory leak related to pmd not attached to the pgd

Meelis Roos
2015-07-20T19:24:59Z

> Hi Christophe,
>
> On 13.07.2015 11:32, Christophe JAILLET wrote:
> > Commit 0e0da48dee8d ("parisc: mm: don't count preallocated pmds")
> > introduced a memory leak.
> >
> > After this commit, the 'return' statement in pmd_free is executed in all
> > cases. Even for pmd that are not attached to the pgd.
> > So 'free_pages' can never be called anymore, leading to a memory leak.
>
> That's really great!!! Thanks for spotting this!
>
> I assume this fixes the leak which killed our debian buildds with OOM
> after an uptime of 1-4 days and which only happened since kernel 4.0.
> Meelis Roos reported the issue already in this thread:
> http://marc.info/?l=linux-parisc&m=142999113232154&w=2

Yes, the patch that is merged in 4.2-rc3 fixed my RP3410 with 1G RAM.

--
Meelis Roos (mroos@linux.ee)