From 8a3514d348de87a9d5e2ac00fbac4faae0b97996 Mon Sep 17 00:00:00 2001 From: Sanjeev Yadav Date: Fri, 23 May 2025 13:14:01 -0700 Subject: [PATCH] scsi: core: ufs: Fix a hang in the error handler ufshcd_err_handling_prepare() calls ufshcd_rpm_get_sync(). The latter function can only succeed if UFSHCD_EH_IN_PROGRESS is not set because resuming involves submitting a SCSI command and ufshcd_queuecommand() returns SCSI_MLQUEUE_HOST_BUSY if UFSHCD_EH_IN_PROGRESS is set. Fix this hang by setting UFSHCD_EH_IN_PROGRESS after ufshcd_rpm_get_sync() has been called instead of before. Backtrace: __switch_to+0x174/0x338 __schedule+0x600/0x9e4 schedule+0x7c/0xe8 schedule_timeout+0xa4/0x1c8 io_schedule_timeout+0x48/0x70 wait_for_common_io+0xa8/0x160 //waiting on START_STOP wait_for_completion_io_timeout+0x10/0x20 blk_execute_rq+0xe4/0x1e4 scsi_execute_cmd+0x108/0x244 ufshcd_set_dev_pwr_mode+0xe8/0x250 __ufshcd_wl_resume+0x94/0x354 ufshcd_wl_runtime_resume+0x3c/0x174 scsi_runtime_resume+0x64/0xa4 rpm_resume+0x15c/0xa1c __pm_runtime_resume+0x4c/0x90 // Runtime resume ongoing ufshcd_err_handler+0x1a0/0xd08 process_one_work+0x174/0x808 worker_thread+0x15c/0x490 kthread+0xf4/0x1ec ret_from_fork+0x10/0x20 Signed-off-by: Sanjeev Yadav [ bvanassche: rewrote patch description ] Fixes: 62694735ca95 ("[SCSI] ufs: Add runtime PM support for UFS host controller driver") Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20250523201409.1676055-1-bvanassche@acm.org Reviewed-by: Peter Wang Signed-off-by: Martin K. Petersen --- drivers/ufs/core/ufshcd.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c index a7513f256057..a1d7c8660c1b 100644 --- a/drivers/ufs/core/ufshcd.c +++ b/drivers/ufs/core/ufshcd.c @@ -6623,9 +6623,14 @@ static void ufshcd_err_handler(struct work_struct *work) up(&hba->host_sem); return; } - ufshcd_set_eh_in_progress(hba); spin_unlock_irqrestore(hba->host->host_lock, flags); + ufshcd_err_handling_prepare(hba); + + spin_lock_irqsave(hba->host->host_lock, flags); + ufshcd_set_eh_in_progress(hba); + spin_unlock_irqrestore(hba->host->host_lock, flags); + /* Complete requests that have door-bell cleared by h/w */ ufshcd_complete_requests(hba, false); spin_lock_irqsave(hba->host->host_lock, flags); -- 2.25.1