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Date:   Mon, 25 Sep 2023 17:06:42 +0200
From:   Miquel Raynal <miquel.raynal@bootlin.com>
To:     Richard Weinberger <richard@nod.at>
Cc:     ZhaoLong Wang <wangzhaolong1@huawei.com>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        linux-mtd <linux-mtd@lists.infradead.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        chengzhihao1 <chengzhihao1@huawei.com>,
        yi zhang <yi.zhang@huawei.com>,
        yangerkun <yangerkun@huawei.com>
Subject: Re: [RFC] mtd: Fix error code loss in mtdchar_read() function.
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richard@nod.at wrote on Mon, 25 Sep 2023 16:59:31 +0200 (CEST):

> ----- Urspr=C3=BCngliche Mail -----
> > Von: "Miquel Raynal" <miquel.raynal@bootlin.com> =20
> >> 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:
> >>=20
> >>                 /*
> >>                  * The driver should never return -EBADMSG if it faile=
d to read
> >>                  * all the requested data. But some buggy drivers migh=
t do
> >>                  * this, so we change it to -EIO.
> >>                  */
> >>                 if (read !=3D len && mtd_is_eccerr(err)) {
> >>                         ubi_assert(0);
> >>                         err =3D -EIO;
> >>                 } =20
> >=20
> > Interesting. Shall we add this check to the mtd_read() path as well?
> >=20
> > Maybe with a WARN_ON()? =20
>=20
> WARN_ON_ONCE(), please. But yes, let's add it.

Zhaolong, can you take care of it?

>=20
> Thanks,
> //richard


Thanks,
Miqu=C3=A8l