percpu: acquire pcpu_lock when updating pcpu_nr_empty_pop_pages
authorTahsin Erdogan <tahsin@google.com>
Sat, 25 Feb 2017 21:00:19 +0000 (13:00 -0800)
committerTejun Heo <tj@kernel.org>
Mon, 6 Mar 2017 20:55:39 +0000 (15:55 -0500)
commit320661b08dd6f1746d5c7ab4eb435ec64b97cd45
treebb7249336a8e2d2ab0d2d22689a5737dd78bf3e0
parentc1ae3cfa0e89fa1a7ecc4c99031f5e9ae99d9201
percpu: acquire pcpu_lock when updating pcpu_nr_empty_pop_pages

Update to pcpu_nr_empty_pop_pages in pcpu_alloc() is currently done
without holding pcpu_lock. This can lead to bad updates to the variable.
Add missing lock calls.

Fixes: b539b87fed37 ("percpu: implmeent pcpu_nr_empty_pop_pages and chunk->nr_populated")
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org # v3.18+
mm/percpu.c