Re: [RFC] mtd: Fix error code loss in mtdchar_read() function.

From: Richard Weinberger
Date: Mon Sep 25 2023 - 10:59:47 EST


----- Ursprüngliche Mail -----
> Von: "Miquel Raynal" <miquel.raynal@xxxxxxxxxxx>
>> Given this a second thought. I don't think a NAND driver is allowed to return
>> less than requests bytes and setting EBADMSG.
>> UBI's IO path has a comment on that:
>>
>> /*
>> * The driver should never return -EBADMSG if it failed to read
>> * all the requested data. But some buggy drivers might do
>> * this, so we change it to -EIO.
>> */
>> if (read != len && mtd_is_eccerr(err)) {
>> ubi_assert(0);
>> err = -EIO;
>> }
>
> Interesting. Shall we add this check to the mtd_read() path as well?
>
> Maybe with a WARN_ON()?

WARN_ON_ONCE(), please. But yes, let's add it.

Thanks,
//richard