From 5592eae7846ca1279591624ecf89513dfb5840bb Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Tue, 9 Feb 2021 04:47:50 +0000 Subject: [PATCH] io_uring: drop mm/files between task_work_submit [ Upstream commit aec18a57edad562d620f7d19016de1fc0cc2208c ] Since SQPOLL task can be shared and so task_work entries can be a mix of them, we need to drop mm and files before trying to issue next request. Cc: stable@vger.kernel.org # 5.10+ Signed-off-by: Pavel Begunkov Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- fs/io_uring.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/io_uring.c b/fs/io_uring.c index fca3a6c45eea..d0b7332ca703 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2084,6 +2084,9 @@ static void __io_req_task_submit(struct io_kiocb *req) else __io_req_task_cancel(req, -EFAULT); mutex_unlock(&ctx->uring_lock); + + if (ctx->flags & IORING_SETUP_SQPOLL) + io_sq_thread_drop_mm(); } static void io_req_task_submit(struct callback_head *cb)