On Thu, Dec 02, 2021 at 12:47:41PM -0700, Jens Axboe wrote:
> When we attempt to merge off the cached request path, we return NULL
> if successful. This makes the caller believe that it's should allocate
> a new request, and hence we end up with the bio both merged and associated
> with a new request. This, predictably, leads to all sorts of crashes.
>
> Pass in a pointer to the bio pointer, and clear it for the merge case.
> Then the caller knows that the bio is already queued, and no new requests
> need to get allocated.
>
> Fixes: 5b13bc8a3fd5 ("blk-mq: cleanup request allocation")
> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Io hang in io_uring workload can't be triggered any more with this
patch:
Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxx>
--
Ming
