From 62132c158d389fc8de49900eae3e02678eb2e220 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Fri, 1 May 2026 19:23:12 +0800 Subject: [PATCH] ublk: don't issue uring_cmd from fallback task work When ublk_ch_uring_cmd_cb() runs as fallback task work (e.g., because the submitting task is exiting), the command should not be issued as current is a kworker, not the daemon task. This can cause io->task to capture the wrong task in __ublk_fetch(), leading to a task mismatch warning in ublk_uring_cmd_cancel_fn(). Check tw.cancel and return -ECANCELED instead of issuing the command from fallback context. Fixes: 3421c7f68bba ("ublk: make sure io cmd handled in submitter task context") Signed-off-by: Ming Lei --- drivers/block/ublk_drv.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index 8e5f3738c203..d10460d29e4a 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -3496,8 +3496,10 @@ static void ublk_ch_uring_cmd_cb(struct io_tw_req tw_req, io_tw_token_t tw) { unsigned int issue_flags = IO_URING_CMD_TASK_WORK_ISSUE_FLAGS; struct io_uring_cmd *cmd = io_uring_cmd_from_tw(tw_req); - int ret = ublk_ch_uring_cmd_local(cmd, issue_flags); + int ret = -ECANCELED; + if (!tw.cancel) + ret = ublk_ch_uring_cmd_local(cmd, issue_flags); if (ret != -EIOCBQUEUED) io_uring_cmd_done(cmd, ret, issue_flags); }