This is a note to let you know that I've just added the patch titled io_uring: kill fasync to the 5.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: io_uring-kill-fasync.patch and it can be found in the queue-5.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit afc14c8d7826b1c45a27eb386bb732c582811bbe Author: Pavel Begunkov <asml.silence@xxxxxxxxx> Date: Fri Oct 1 10:39:33 2021 +0100 io_uring: kill fasync [ Upstream commit 3f008385d46d3cea4a097d2615cd485f2184ba26 ] We have never supported fasync properly, it would only fire when there is something polling io_uring making it useless. The original support came in through the initial io_uring merge for 5.1. Since it's broken and nobody has reported it, get rid of the fasync bits. Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx> Link: https://lore.kernel.org/r/2f7ca3d344d406d34fa6713824198915c41cea86.1633080236.git.asml.silence@xxxxxxxxx Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/io_uring.c b/fs/io_uring.c index 675216f7022d..2f79586c1a7c 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -419,7 +419,6 @@ struct io_ring_ctx { struct wait_queue_head cq_wait; unsigned cq_extra; atomic_t cq_timeouts; - struct fasync_struct *cq_fasync; unsigned cq_last_tm_flush; } ____cacheline_aligned_in_smp; @@ -1448,10 +1447,8 @@ static void io_cqring_ev_posted(struct io_ring_ctx *ctx) wake_up(&ctx->sq_data->wait); if (io_should_trigger_evfd(ctx)) eventfd_signal(ctx->cq_ev_fd, 1); - if (waitqueue_active(&ctx->poll_wait)) { + if (waitqueue_active(&ctx->poll_wait)) wake_up_interruptible(&ctx->poll_wait); - kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN); - } } static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx) @@ -1465,10 +1462,8 @@ static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx) } if (io_should_trigger_evfd(ctx)) eventfd_signal(ctx->cq_ev_fd, 1); - if (waitqueue_active(&ctx->poll_wait)) { + if (waitqueue_active(&ctx->poll_wait)) wake_up_interruptible(&ctx->poll_wait); - kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN); - } } /* Returns true if there are no backlogged entries after the flush */ @@ -8779,13 +8774,6 @@ static __poll_t io_uring_poll(struct file *file, poll_table *wait) return mask; } -static int io_uring_fasync(int fd, struct file *file, int on) -{ - struct io_ring_ctx *ctx = file->private_data; - - return fasync_helper(fd, file, on, &ctx->cq_fasync); -} - static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id) { const struct cred *creds; @@ -9571,7 +9559,6 @@ static const struct file_operations io_uring_fops = { .mmap_capabilities = io_uring_nommu_mmap_capabilities, #endif .poll = io_uring_poll, - .fasync = io_uring_fasync, #ifdef CONFIG_PROC_FS .show_fdinfo = io_uring_show_fdinfo, #endif