From mboxrd@z Thu Jan 1 00:00:00 1970 From: Meelis Roos Date: Mon, 20 Jul 2015 19:28:56 +0000 Subject: Re: [PATCH] parisc: mm: Fix a memory leak related to pmd not attached to the pgd Message-Id: List-Id: References: <1436779963-4286-1-git-send-email-christophe.jaillet@wanadoo.fr> <55A408F5.601@gmx.de> In-Reply-To: <55A408F5.601@gmx.de> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Helge Deller Cc: Christophe JAILLET , jejb@parisc-linux.org, mpatocka@redhat.com, kirill.shutemov@linux.intel.com, linux-parisc@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org, John David Anglin > 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&m2999113232154&w=2 Yes, the patch that is merged in 4.2-rc3 fixed my RP3410 with 1G RAM. -- Meelis Roos (mroos@linux.ee)