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() which is
safe under RCU lock.Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Tetsuo Handa <[email protected]> Cc: Oleg Nesterov <[email protected]> --- block/ioprio.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/block/ioprio.c b/block/ioprio.c index 01b8116..3790669 100644 --- a/block/ioprio.c +++ b/block/ioprio.c @@ -122,14 +122,14 @@ int set_task_ioprio(struct task_struct *task, int ioprio) if (!user) break; - do_each_thread(g, p) { + for_each_process_thread(g, p) { if (!uid_eq(task_uid(p), uid) || !task_pid_vnr(p)) continue; ret = set_task_ioprio(p, ioprio); if (ret) goto free_uid; - } while_each_thread(g, p); + } free_uid: if (who) free_uid(user); @@ -222,7 +222,7 @@ int ioprio_best(unsigned short aprio, unsigned short bprio) if (!user) break; - do_each_thread(g, p) { + for_each_process_thread(g, p) { if (!uid_eq(task_uid(p), user->uid) || !task_pid_vnr(p)) continue; @@ -233,7 +233,7 @@ int ioprio_best(unsigned short aprio, unsigned short bprio) ret = tmpio; else ret = ioprio_best(ret, tmpio); - } while_each_thread(g, p); + } if (who) free_uid(user); -- 1.8.3.1
