diff options
| author | Pavel Begunkov <asml.silence@gmail.com> | 2024-11-04 16:12:04 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-09-25 11:13:47 +0200 |
| commit | 9b71bfefc405100f91c08618a248a4dd64e41b2d (patch) | |
| tree | 41908dba291fe4a29416bc71fa869d8861b6f57f | |
| parent | 9ffc5f132a35bd7d7a9258913d4cfe36277e2db1 (diff) | |
io_uring/cmd: let cmds to know about dying task
Commit df3b8ca604f224eb4cd51669416ad4d607682273 upstream.
When the taks that submitted a request is dying, a task work for that
request might get run by a kernel thread or even worse by a half
dismantled task. We can't just cancel the task work without running the
callback as the cmd might need to do some clean up, so pass a flag
instead. If set, it's not safe to access any task resources and the
callback is expected to cancel the cmd ASAP.
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | include/linux/io_uring_types.h | 1 | ||||
| -rw-r--r-- | io_uring/uring_cmd.c | 6 |
2 files changed, 6 insertions, 1 deletions
diff --git a/include/linux/io_uring_types.h b/include/linux/io_uring_types.h index 61675ea95e0b..42fab0b501f2 100644 --- a/include/linux/io_uring_types.h +++ b/include/linux/io_uring_types.h @@ -37,6 +37,7 @@ enum io_uring_cmd_flags { /* set when uring wants to cancel a previously issued command */ IO_URING_F_CANCEL = (1 << 11), IO_URING_F_COMPAT = (1 << 12), + IO_URING_F_TASK_DEAD = (1 << 13), }; struct io_wq_work_node { diff --git a/io_uring/uring_cmd.c b/io_uring/uring_cmd.c index b2ce4b561002..13917967c52f 100644 --- a/io_uring/uring_cmd.c +++ b/io_uring/uring_cmd.c @@ -116,9 +116,13 @@ EXPORT_SYMBOL_GPL(io_uring_cmd_mark_cancelable); static void io_uring_cmd_work(struct io_kiocb *req, struct io_tw_state *ts) { struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); + unsigned int flags = IO_URING_F_COMPLETE_DEFER; + + if (current->flags & (PF_EXITING | PF_KTHREAD)) + flags |= IO_URING_F_TASK_DEAD; /* task_work executor checks the deffered list completion */ - ioucmd->task_work_cb(ioucmd, IO_URING_F_COMPLETE_DEFER); + ioucmd->task_work_cb(ioucmd, flags); } void __io_uring_cmd_do_in_task(struct io_uring_cmd *ioucmd, |