Re: [PATCH] mmc: block: ioctl: Poll for TRAN if possible

From: Christian Löhle
Date: Fri Jun 18 2021 - 06:01:01 EST

>Poll for TRAN state if the ioctl command will eventually return to TRAN
>The ioctl submitted command should not be considered completed until
>the card has returned back to TRAN state. Waiting just for the card
>to no longer signal busy is not enough as they might remain in a
>non-busy PROG state for a while after the command.
>Further commands requiring TRAN will fail then.
>It should not be the responsibility of the user to check if their command
>has completed until sending the next via ioctl,
>instead the check should be made here.
>So now, in doubt, wait for TRAN except for the few commands that will
>never return to TRAN state.

So apart from the fact that I missed a couple of non-TRAN returning MMC
commands, which I will add in v2, are there any other thoughts about this
patch? It would change the behavior of the ioctl interface, but I think it is
the only way to prevent race conditions here.

Best Regards,

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