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Jiayi Li
99d7ab8db9
The existing memstick core patch: commit62c59a8786("memstick: Skip allocating card when removing host") sets host->removing in memstick_remove_host(),but still exists a critical time window where memstick_check can run after host->eject is set but before removing is set. In the rtsx_usb_ms driver, the problematic sequence is: rtsx_usb_ms_drv_remove: memstick_check: host->eject = true cancel_work_sync(handle_req) if(!host->removing) ... memstick_alloc_card() memstick_set_rw_addr() memstick_new_req() rtsx_usb_ms_request() if(!host->eject) skip schedule_work wait_for_completion() memstick_remove_host: [blocks indefinitely] host->removing = true flush_workqueue() [block] 1. rtsx_usb_ms_drv_remove sets host->eject = true 2. cancel_work_sync(&host->handle_req) runs 3. memstick_check work may be executed here <-- danger window 4. memstick_remove_host sets removing = 1 During this window (step 3), memstick_check calls memstick_alloc_card, which may indefinitely waiting for mrq_complete completion that will never occur because rtsx_usb_ms_request sees eject=true and skips scheduling work, memstick_set_rw_addr waits forever for completion. This causes a deadlock when memstick_remove_host tries to flush_workqueue, waiting for memstick_check to complete, while memstick_check is blocked waiting for mrq_complete completion. Fix this by setting removing=true at the start of rtsx_usb_ms_drv_remove, before any work cancellation. This ensures memstick_check will see the removing flag immediately and exit early, avoiding the deadlock. Fixes:62c59a8786("memstick: Skip allocating card when removing host") Signed-off-by: Jiayi Li <lijiayi@kylinos.cn> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250804013604.1311218-1-lijiayi@kylinos.cn Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Linux kernel
============
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