diff mbox

blktrace: fix trace mutex deadlock

Message ID a0e84358-d9af-4999-4512-3219f0d558ac@kernel.dk (mailing list archive)
State New, archived
Headers show

Commit Message

Jens Axboe Nov. 19, 2017, 6:52 p.m. UTC
A previous commit changed the locking around registration/cleanup,
but direct callers of blk_trace_remove() were missed. This means
that if we hit the error path in setup, we will deadlock on
attempting to re-acquire the queue trace mutex.

Fixes: 1f2cac107c59 ("blktrace: fix unlocked access to init/start-stop/teardown")
Signed-off-by: Jens Axboe <axboe@kernel.dk>

---
diff mbox

Patch

diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 206e0e2ace53..f224985de5fa 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -591,7 +591,7 @@  static int __blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
 		return ret;
 
 	if (copy_to_user(arg, &buts, sizeof(buts))) {
-		blk_trace_remove(q);
+		__blk_trace_remove(q);
 		return -EFAULT;
 	}
 	return 0;
@@ -637,7 +637,7 @@  static int compat_blk_trace_setup(struct request_queue *q, char *name,
 		return ret;
 
 	if (copy_to_user(arg, &buts.name, ARRAY_SIZE(buts.name))) {
-		blk_trace_remove(q);
+		__blk_trace_remove(q);
 		return -EFAULT;
 	}