On 2/03/21 5:21 am, Asutosh Das wrote: > During runtime-suspend of ufs host, the scsi devices are > already suspended and so are the queues associated with them. > But the ufs host sends SSU to wlun during its runtime-suspend. > During the process blk_queue_enter checks if the queue is not in > suspended state. If so, it waits for the queue to resume, and never > comes out of it. > The commit > (d55d15a33: scsi: block: Do not accept any requests while suspended) > adds the check if the queue is in suspended state in blk_queue_enter(). > > Call trace: > __switch_to+0x174/0x2c4 > __schedule+0x478/0x764 > schedule+0x9c/0xe0 > blk_queue_enter+0x158/0x228 > blk_mq_alloc_request+0x40/0xa4 > blk_get_request+0x2c/0x70 > __scsi_execute+0x60/0x1c4 > ufshcd_set_dev_pwr_mode+0x124/0x1e4 > ufshcd_suspend+0x208/0x83c > ufshcd_runtime_suspend+0x40/0x154 > ufshcd_pltfrm_runtime_suspend+0x14/0x20 > pm_generic_runtime_suspend+0x28/0x3c > __rpm_callback+0x80/0x2a4 > rpm_suspend+0x308/0x614 > rpm_idle+0x158/0x228 > pm_runtime_work+0x84/0xac > process_one_work+0x1f0/0x470 > worker_thread+0x26c/0x4c8 > kthread+0x13c/0x320 > ret_from_fork+0x10/0x18 > > Fix this by registering ufs device wlun as a scsi driver and > registering it for block runtime-pm. Also make this as a > supplier for all other luns. That way, this device wlun > suspends after all the consumers and resumes after > hba resumes. > > Co-developed-by: Can Guo <cang@xxxxxxxxxxxxxx> > Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx> > Signed-off-by: Asutosh Das <asutoshd@xxxxxxxxxxxxxx> > --- Now we need either to move the suspend/resume vops from ufshcd_suspend/resume to __ufshcd_wl_suspend/resume, assuming that would work for existing implementations of those callbacks, or otherwise create new vops ->wl_suspend() / ->wl_resume(), and then split the existing implementations of those callbacks. ufs_intel_resume() now needs to be invoked from __ufshcd_wl_resume(). I am not sure about the others: exynos_ufs_suspend() exynos_ufs_resume() ufs_hisi_suspend() ufs_hisi_resume() ufs_mtk_suspend() ufs_mtk_resume() ufs_qcom_suspend() ufs_qcom_resume()