blktrace: fix trace mutex deadlock (2967acbb) · Commits · 戴 / test

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: ("blktrace: fix unlocked access to init/start-stop/teardown") Signed-off-by:

Jens Axboe <axboe@kernel.dk>

kernel/trace/blktrace.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -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;
		}

Admin message