Re: [PATCH v4 1/2] ufs: rpmb: retry power-on UNIT ATTENTION on the RPMB WLUN

[Bean Huo]

On Thu, 2026-08-27 at 09:03 +0200, Jorge Ramirez-Ortiz wrote:
> After a power cycle, the first command sent to any UFS logical unit
> completes with CHECK CONDITION reporting a power-on UNIT ATTENTION.
> The SCSI core surfaces this condition to the caller rather than
> retrying it.
> 
> For the RPMB well-known LU the first command after boot is the first
> RPMB frame, and RPMB has no earlier, guaranteed access that could clear
> the condition beforehand. The power-on UNIT ATTENTION therefore reaches
> RPMB and fails that first frame, breaking RPMB on every cold boot.
> 
> The RPMB WLUN needs the power-on UNIT ATTENTION to be retried so that
> RPMB works from the very first access after a power cycle.
> 
> Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez@xxxxxxxxxxxxxxxx>

Reviewed-by: Bean Huo <beanhuo@xxxxxxxxxx>