RE: [PATCH v1 1/1] ufs: core: set SDEV_OFFLINE when ufs shutdown.

["Seunghwan Baek" <sh8267.baek@samsung.com>]

> There is a history of dead lock as reboot is performed at the beginning of
> booting. SDEV_QUIESCE was set for all lu's scsi_devices by ufs shutdown,
> and at that time the audio driver was waiting on blk_mq_submit_bio holding
> a mutex_lock while reading the fw binary. After that, a deadlock issue
> occurred while audio driver shutdown was waiting for mutex_unlock of
> blk_mq_submit_bio. To solve this, set SDEV_OFFLINE for all lus except wlun,
> so that any i/o that comes down after a ufs shutdown will return an error.
> 
> [   31.907781]I[0:      swapper/0:    0]        1        130705007       1651079834
> 11289729804                0 D(   2) 3 ffffff882e208000 *             init
> [device_shutdown]
> [   31.907793]I[0:      swapper/0:    0] Mutex: 0xffffff8849a2b8b0:
> owner[0xffffff882e28cb00 kworker/6:0 :49]
> [   31.907806]I[0:      swapper/0:    0] Call trace:
> [   31.907810]I[0:      swapper/0:    0]  __switch_to+0x174/0x338
> [   31.907819]I[0:      swapper/0:    0]  __schedule+0x5ec/0x9cc
> [   31.907826]I[0:      swapper/0:    0]  schedule+0x7c/0xe8
> [   31.907834]I[0:      swapper/0:    0]  schedule_preempt_disabled+0x24/0x40
> [   31.907842]I[0:      swapper/0:    0]  __mutex_lock+0x408/0xdac
> [   31.907849]I[0:      swapper/0:    0]  __mutex_lock_slowpath+0x14/0x24
> [   31.907858]I[0:      swapper/0:    0]  mutex_lock+0x40/0xec
> [   31.907866]I[0:      swapper/0:    0]  device_shutdown+0x108/0x280
> [   31.907875]I[0:      swapper/0:    0]  kernel_restart+0x4c/0x11c
> [   31.907883]I[0:      swapper/0:    0]  __arm64_sys_reboot+0x15c/0x280
> [   31.907890]I[0:      swapper/0:    0]  invoke_syscall+0x70/0x158
> [   31.907899]I[0:      swapper/0:    0]  el0_svc_common+0xb4/0xf4
> [   31.907909]I[0:      swapper/0:    0]  do_el0_svc+0x2c/0xb0
> [   31.907918]I[0:      swapper/0:    0]  el0_svc+0x34/0xe0
> [   31.907928]I[0:      swapper/0:    0]  el0t_64_sync_handler+0x68/0xb4
> [   31.907937]I[0:      swapper/0:    0]  el0t_64_sync+0x1a0/0x1a4
> 
> [   31.908774]I[0:      swapper/0:    0]       49                0         11960702
> 11236868007                0 D(   2) 6 ffffff882e28cb00 *      kworker/6:0
> [__bio_queue_enter]
> [   31.908783]I[0:      swapper/0:    0] Call trace:
> [   31.908788]I[0:      swapper/0:    0]  __switch_to+0x174/0x338
> [   31.908796]I[0:      swapper/0:    0]  __schedule+0x5ec/0x9cc
> [   31.908803]I[0:      swapper/0:    0]  schedule+0x7c/0xe8
> [   31.908811]I[0:      swapper/0:    0]  __bio_queue_enter+0xb8/0x178
> [   31.908818]I[0:      swapper/0:    0]  blk_mq_submit_bio+0x194/0x67c
> [   31.908827]I[0:      swapper/0:    0]  __submit_bio+0xb8/0x19c
> 
> Fixes: b294ff3e3449 ("scsi: ufs: core: Enable power management for wlun")
> Cc: stable@vger.kernel.org
> Signed-off-by: Seunghwan Baek <sh8267.baek@samsung.com>
> ---
>  drivers/ufs/core/ufshcd.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
> index a6f818cdef0e..4ac1492787c2 100644
> --- a/drivers/ufs/core/ufshcd.c
> +++ b/drivers/ufs/core/ufshcd.c
> @@ -10215,7 +10215,9 @@ static void ufshcd_wl_shutdown(struct device *dev)
>  	shost_for_each_device(sdev, hba->host) {
>  		if (sdev == hba->ufs_device_wlun)
>  			continue;
> -		scsi_device_quiesce(sdev);
> +		mutex_lock(&sdev->state_mutex);
> +		scsi_device_set_state(sdev, SDEV_OFFLINE);
> +		mutex_unlock(&sdev->state_mutex);
>  	}
>  	__ufshcd_wl_suspend(hba, UFS_SHUTDOWN_PM);
> 
> --
> 2.17.1
> 

Dear all.

Could you please review this patch? It's been almost a month.
If you have any opinions about this patch, share and comment it.

Thanks.
BRs.