block: use for_each_thread() in sys_ioprio_set()/sys_ioprio_get()
authorTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Wed, 22 Feb 2017 23:40:50 +0000 (15:40 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 23 Feb 2017 00:41:27 +0000 (16:41 -0800)
commit612dafabb6a0fa62e9b86f11da5d37ee11dea28f
treeaa28468a75fa6fa60717e1904edadd9e888e3fef
parent6302666d2ef135be46ca34226791afea275f62d1
block: use for_each_thread() in sys_ioprio_set()/sys_ioprio_get()

IOPRIO_WHO_USER case in sys_ioprio_set()/sys_ioprio_get() are using
while_each_thread(), which is unsafe under RCU lock according to commit
0c740d0afc3bff0a ("introduce for_each_thread() to replace the buggy
while_each_thread()").  Use for_each_thread() (via
for_each_process_thread()) which is safe under RCU lock.

Link: http://lkml.kernel.org/r/201702011947.DBD56740.OMVHOLOtSJFFFQ@I-love.SAKURA.ne.jp
Link: http://lkml.kernel.org/r/1486041779-4401-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
block/ioprio.c