Revert "fs/aio: Make io_cancel() generate completions again"

Revert "fs/aio: Make io_cancel() generate completions again"

Patch "fs/aio: Make io_cancel() generate completions again" is based on the
assumption that calling kiocb->ki_cancel() does not complete R/W requests.
This is incorrect: the two drivers that call kiocb_set_cancel_fn() callers
set a cancellation function that calls usb_ep_dequeue(). According to its
documentation, usb_ep_dequeue() calls the completion routine with status
-ECONNRESET. Hence this revert.

Cc: Benjamin LaHaise <ben@communityfibre.ca>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Avi Kivity <avi@scylladb.com>
Cc: Sandeep Dhavale <dhavale@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: stable@vger.kernel.org
Reported-by: syzbot+b91eb2ed18f599dd3c31@syzkaller.appspotmail.com
Fixes: 54cbc058d86b ("fs/aio: Make io_cancel() generate completions again")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240304182945.3646109-1-bvanassche@acm.org
Acked-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>