From b4bb6daf4ac4d4560044ecdd81e93aa2f6acbb06 Mon Sep 17 00:00:00 2001 From: Brian Kao Date: Wed, 12 Nov 2025 06:32:02 +0000 Subject: [PATCH] scsi: ufs: core: Fix EH failure after W-LUN resume error When a W-LUN resume fails, its parent devices in the SCSI hierarchy, including the scsi_target, may be runtime suspended. Subsequently, the error handler in ufshcd_recover_pm_error() fails to set the W-LUN device back to active because the parent target is not active. This results in the following errors: google-ufshcd 3c2d0000.ufs: ufshcd_err_handler started; HBA state eh_fatal; ... ufs_device_wlun 0:0:0:49488: START_STOP failed for power mode: 1, result 40000 ufs_device_wlun 0:0:0:49488: ufshcd_wl_runtime_resume failed: -5 ... ufs_device_wlun 0:0:0:49488: runtime PM trying to activate child device 0:0:0:49488 but parent (target0:0:0) is not active Address this by: 1. Ensuring the W-LUN's parent scsi_target is runtime resumed before attempting to set the W-LUN to active within ufshcd_recover_pm_error(). 2. Explicitly checking for power.runtime_error on the HBA and W-LUN devices before calling pm_runtime_set_active() to clear the error state. 3. Adding pm_runtime_get_sync(hba->dev) in ufshcd_err_handling_prepare() to ensure the HBA itself is active during error recovery, even if a child device resume failed. These changes ensure the device power states are managed correctly during error recovery. Signed-off-by: Brian Kao Tested-by: Brian Kao Reviewed-by: Bart Van Assche Link: https://patch.msgid.link/20251112063214.1195761-1-powenkao@google.com Signed-off-by: Martin K. Petersen --- drivers/ufs/core/ufshcd.c | 36 ++++++++++++++++++++++++++++-------- 1 file changed, 28 insertions(+), 8 deletions(-) diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c index 040a0ceb170a7..1b3fe1d8655e6 100644 --- a/drivers/ufs/core/ufshcd.c +++ b/drivers/ufs/core/ufshcd.c @@ -6504,6 +6504,11 @@ static void ufshcd_clk_scaling_suspend(struct ufs_hba *hba, bool suspend) static void ufshcd_err_handling_prepare(struct ufs_hba *hba) { + /* + * A WLUN resume failure could potentially lead to the HBA being + * runtime suspended, so take an extra reference on hba->dev. + */ + pm_runtime_get_sync(hba->dev); ufshcd_rpm_get_sync(hba); if (pm_runtime_status_suspended(&hba->ufs_device_wlun->sdev_gendev) || hba->is_sys_suspended) { @@ -6543,6 +6548,7 @@ static void ufshcd_err_handling_unprepare(struct ufs_hba *hba) if (ufshcd_is_clkscaling_supported(hba)) ufshcd_clk_scaling_suspend(hba, false); ufshcd_rpm_put(hba); + pm_runtime_put(hba->dev); } static inline bool ufshcd_err_handling_should_stop(struct ufs_hba *hba) @@ -6557,28 +6563,42 @@ static inline bool ufshcd_err_handling_should_stop(struct ufs_hba *hba) #ifdef CONFIG_PM static void ufshcd_recover_pm_error(struct ufs_hba *hba) { + struct scsi_target *starget = hba->ufs_device_wlun->sdev_target; struct Scsi_Host *shost = hba->host; struct scsi_device *sdev; struct request_queue *q; - int ret; + bool resume_sdev_queues = false; hba->is_sys_suspended = false; + /* - * Set RPM status of wlun device to RPM_ACTIVE, - * this also clears its runtime error. + * Ensure the parent's error status is cleared before proceeding + * to the child, as the parent must be active to activate the child. */ - ret = pm_runtime_set_active(&hba->ufs_device_wlun->sdev_gendev); + if (hba->dev->power.runtime_error) { + /* hba->dev has no functional parent thus simplily set RPM_ACTIVE */ + pm_runtime_set_active(hba->dev); + resume_sdev_queues = true; + } + + if (hba->ufs_device_wlun->sdev_gendev.power.runtime_error) { + /* + * starget, parent of wlun, might be suspended if wlun resume failed. + * Make sure parent is resumed before set child (wlun) active. + */ + pm_runtime_get_sync(&starget->dev); + pm_runtime_set_active(&hba->ufs_device_wlun->sdev_gendev); + pm_runtime_put_sync(&starget->dev); + resume_sdev_queues = true; + } - /* hba device might have a runtime error otherwise */ - if (ret) - ret = pm_runtime_set_active(hba->dev); /* * If wlun device had runtime error, we also need to resume those * consumer scsi devices in case any of them has failed to be * resumed due to supplier runtime resume failure. This is to unblock * blk_queue_enter in case there are bios waiting inside it. */ - if (!ret) { + if (resume_sdev_queues) { shost_for_each_device(sdev, shost) { q = sdev->request_queue; if (q->dev && (q->rpm_status == RPM_SUSPENDED || -- 2.47.3