Sparse flood makes it hard to catch newly-introduced warnings. So let's fix the the sparse warnings in the oom killer:
CHECK mm/oom_kill.c mm/oom_kill.c:139:20: warning: context imbalance in '__find_lock_task_mm' - wrong count at exit mm/oom_kill.c:771:9: warning: context imbalance in 'out_of_memory' - different lock contexts for basic block
The first one is fixed by assuring sparse that we know that we exit with the lock held.
The second one is caused by the fact that sparse isn't smart enough to handle noreturn attribute.
Signed-off-by: Anton Vorontsov anton.vorontsov@linaro.org --- mm/oom_kill.c | 9 ++++++++- 1 files changed, 8 insertions(+), 1 deletions(-)
diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 0ebb383..49569b6 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -142,8 +142,14 @@ struct task_struct *__find_lock_task_mm(struct task_struct *p)
do { task_lock(t); - if (likely(t->mm)) + if (likely(t->mm)) { + /* + * Shut up sparse: we do know that we exit w/ the + * task locked. + */ + __release(&t->alloc_loc); return t; + } task_unlock(t); } while_each_thread(p, t);
@@ -766,6 +772,7 @@ retry: dump_header(NULL, gfp_mask, order, NULL, mpol_mask); read_unlock(&tasklist_lock); panic("Out of memory and no killable processes...\n"); + return; }
if (oom_kill_process(p, gfp_mask, order, points, totalpages, NULL,