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

[Miquel Raynal]

richard at nod.at wrote on Mon, 25 Sep 2023 16:59:31 +0200 (CEST):

> ----- Ursprüngliche Mail -----
> > Von: "Miquel Raynal" <miquel.raynal at bootlin.com>  
> >> 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.

Zhaolong, can you take care of it?

> 
> Thanks,
> //richard


Thanks,
Miquèl