Re: [PATCH] scsi: ufs: Fix incorrect ufshcd_state after ufshcd_reset_and_restore()

[Bean Huo]

On Mon, 2021-03-01 at 21:19 +0200, Adrian Hunter wrote:
> If ufshcd_probe_hba() fails it sets ufshcd_state to
> UFSHCD_STATE_ERROR,
> however, if it is called again, as it is within a loop in
> ufshcd_reset_and_restore(), and succeeds, then it will not set the
> state
> back to UFSHCD_STATE_OPERATIONAL unless the state was
> UFSHCD_STATE_RESET.
> 
> That can result in the state being UFSHCD_STATE_ERROR even though
> ufshcd_reset_and_restore() is successful and returns zero.
> 
> Fix by initializing the state to UFSHCD_STATE_RESET in the start of
> each
> loop in ufshcd_reset_and_restore().  If there is an error,
> ufshcd_reset_and_restore() will change the state to
> UFSHCD_STATE_ERROR,
> otherwise ufshcd_probe_hba() will have set the state appropriately.
> 
> Fixes: 4db7a2360597 ("scsi: ufs: Fix concurrency of error handler and
> other error recovery paths")
> Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>

We used to directly set hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL at
the beginning of ufshcd_probe_hba(), and didn't have checkup if (hba-
>ufshcd_state == UFSHCD_STATE_RESET). Remove this checkup, also works,
but in This loop, it it better that, before going to reset flow,
ufshcd_state should be set UFSHCD_STATE_RESET.


Reviewed-by: Bean Huo <beanhuo@xxxxxxxxxx>