Re: [PATCH v1 1/2] scsi: ufs: Serialize eh_work with system PM events and async scan

[Bean Huo]

On Mon, 2020-09-21 at 22:32 -0700, Can Guo wrote:
> Serialize eh_work with system PM events and async scan to make sure
> eh_work
> does not run in parallel with them.
> 
> Change-Id: I33012c68e2ea443950313c59a4a46ad88cf3c82d
> Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx>
> ---
>  drivers/scsi/ufs/ufshcd.c | 64 +++++++++++++++++++++++++++++------
> ------------
>  drivers/scsi/ufs/ufshcd.h |  1 +
>  2 files changed, 41 insertions(+), 24 deletions(-)
> 
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index 1d8134e..7e764e8 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -5597,7 +5597,9 @@ static inline void
> ufshcd_schedule_eh_work(struct ufs_hba *hba)
>  static void ufshcd_err_handling_prepare(struct ufs_hba *hba)
>  {
>  	pm_runtime_get_sync(hba->dev);
> -	if (pm_runtime_suspended(hba->dev)) {
> +	if (pm_runtime_status_suspended(hba->dev) || hba-
> >is_sys_suspended) {

Hi Can

I curiously want to know how this can be produced in real system.

IMO, The system has been in system PM suspeded mode, how can trigger
error handler? because the tasks have been freezed, the device
interrupts disabled, before entering system PM suspended mode, the
tasks in the queue should be completed, otherwises, there is bug in the
whole flow.


thanks,
Bean