Re: [PATCH v4 4/5] mtd_blkdevs: add option to enable scanning for partitions

Richard Weinberger
2022-11-10T20:12:47Z

----- Ursprüngliche Mail -----
> On Thu, Nov 10, 2022 at 08:44:53PM +0100, Richard Weinberger wrote:
>> ----- Ursprüngliche Mail -----
>> > Von: "Daniel Golle" <daniel@makrotopia.org>
>> > +
>> > + if (!IS_ENABLED(CONFIG_MTD_BLOCK_PARTITIONS) || mtd_type_is_nand(new->mtd))
>> > + gd->flags |= GENHD_FL_NO_PART;
>>
>> I know that NAND should not get used with mtdblock because lack of wearleveling
>> and
>> in general too many writes. But what exactly is the rationale to deny part
>> scanning for NAND?
>
> As UBI should be used on NAND, partition scanning should be enabled for
> ubiblock devices to have uImage.FIT filesystem subimages mapped by the
> partition parser.
>
> If not skipping partition scanning on NAND-backed mtdblock devices the
> scanning itself will already trigger multiple warnings which now happen
> every time when a NAND-backed mtdblock device is being opened since
> commit 96a3295c ("mtdblock: warn if opened on NAND").

I see, you want to promote UBI. Makes sense.
In case you do a v5 series, please add a comment to the code.

Thanks,
//richard