Re: [PATCH] mtd: nand: Fix build error while CONFIG_MTD_NAND_ECC_SW_BCH is set to module

From: Boris Brezillon
Date: Fri Apr 12 2019 - 11:04:59 EST


On Fri, 12 Apr 2019 22:28:57 +0800
YueHaibing <yuehaibing@xxxxxxxxxx> wrote:

> On 2019/4/11 1:03, Boris Brezillon wrote:
> > On Wed, 10 Apr 2019 18:18:43 +0200
> > Miquel Raynal <miquel.raynal@xxxxxxxxxxx> wrote:
> >
> >> Hi YueHaibing,
> >>
> >> YueHaibing <yuehaibing@xxxxxxxxxx> wrote on Wed, 10 Apr 2019 23:03:24
> >> +0800:
> >>
> >>> On 2019/4/10 22:29, Boris Brezillon wrote:
> >>>> On Wed, 10 Apr 2019 22:22:16 +0800
> >>>> YueHaibing <yuehaibing@xxxxxxxxxx> wrote:
> >>>>
> >>>>> On 2019/4/10 21:58, Boris Brezillon wrote:
> >>>>>> On Wed, 10 Apr 2019 15:39:28 +0200
> >>>>>> Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx> wrote:
> >>>>>>
> >>>>>>> On Wed, 10 Apr 2019 21:07:47 +0800
> >>>>>>> Yue Haibing <yuehaibing@xxxxxxxxxx> wrote:
> >>>>>>>
> >>>>>>>> From: YueHaibing <yuehaibing@xxxxxxxxxx>
> >>>>>>>>
> >>>>>>>> Fix gcc build error while CONFIG_MTD_NAND_ECC_SW_BCH
> >>>>>>>> is set to module:
> >>>>>>>>
> >>>>>>>> drivers/mtd/nand/raw/nand_base.o: In function `nand_cleanup':
> >>>>>>>> (.text+0xef6): undefined reference to `nand_bch_free'
> >>>>>>>> drivers/mtd/nand/raw/nand_base.o: In function `nand_scan_tail':
> >>>>>>>> nand_base.c:(.text+0xa101): undefined reference to `nand_bch_calculate_ecc'
> >>>>>>>> nand_base.c:(.text+0xa120): undefined reference to `nand_bch_correct_data'
> >>>>>>>> nand_base.c:(.text+0xa269): undefined reference to `nand_bch_init'
> >>>>>>>>
> >>>>>>>> CONFIG_MTD_NAND_ECC_SW_BCH should not be set to M,
> >>>>>>>> because MTD_RAW_NAND need it while linked.
> >>>>>>>>
> >>>>>>>> Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
> >>>>>>>> Fixes: 193bd4002644 ("mtd: nand: add software BCH ECC support"
> >>>>>>>
> >>>>>>> Nope, it's not this one that introduced the regression.
> >>>>>>>
> >>>>>>>
> >>>>>>>
> >>>>>>>> Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx>
> >>>>>>>> ---
> >>>>>>>> drivers/mtd/nand/raw/Kconfig | 2 +-
> >>>>>>>> 1 file changed, 1 insertion(+), 1 deletion(-)
> >>>>>>>>
> >>>>>>>> diff --git a/drivers/mtd/nand/raw/Kconfig b/drivers/mtd/nand/raw/Kconfig
> >>>>>>>> index 615d738..0500c42 100644
> >>>>>>>> --- a/drivers/mtd/nand/raw/Kconfig
> >>>>>>>> +++ b/drivers/mtd/nand/raw/Kconfig
> >>>>>>>> @@ -22,7 +22,7 @@ menuconfig MTD_RAW_NAND
> >>>>>>>> if MTD_RAW_NAND
> >>>>>>>>
> >>>>>>>> config MTD_NAND_ECC_SW_BCH
> >>>>>>>> - tristate "Support software BCH ECC"
> >>>>>>>> + bool "Support software BCH ECC"
> >>>>>>>> select BCH
> >>>>>>>> default n
> >>>>>>>> help
> >>>>>>>
> >>>>>>> Should be fixed with the following diff squashed into:
> >>>>>>>
> >>>>>>> 51ef1d0b2095 ("mtd: nand: Clarify Kconfig entry for software BCH ECC algorithm")
> >>>>>>>
> >>>>>>> --->8---
> >>>>>>> diff --git a/include/linux/mtd/nand_bch.h b/include/linux/mtd/nand_bch.h
> >>>>>>> index b8106651f807..06ce2b655c13 100644
> >>>>>>> --- a/include/linux/mtd/nand_bch.h
> >>>>>>> +++ b/include/linux/mtd/nand_bch.h
> >>>>>>> @@ -15,7 +15,7 @@ struct mtd_info;
> >>>>>>> struct nand_chip;
> >>>>>>> struct nand_bch_control;
> >>>>>>>
> >>>>>>> -#if defined(CONFIG_MTD_NAND_ECC_BCH)
> >>>>>>> +#if defined(CONFIG_MTD_NAND_ECC_SW_BCH)
> >>>>>>>
> >>>>>>> static inline int mtd_nand_has_bch(void) { return 1; }
> >>>>>>>
> >>>>>>> @@ -39,7 +39,7 @@ struct nand_bch_control *nand_bch_init(struct mtd_info *mtd);
> >>>>>>> */
> >>>>>>> void nand_bch_free(struct nand_bch_control *nbc);
> >>>>>>>
> >>>>>>> -#else /* !CONFIG_MTD_NAND_ECC_BCH */
> >>>>>>> +#else /* !CONFIG_MTD_NAND_ECC_SW_BCH */
> >>>>>>>
> >>>>>>> static inline int mtd_nand_has_bch(void) { return 0; }
> >>>>>>>
> >>>>>>> @@ -64,6 +64,6 @@ static inline struct nand_bch_control *nand_bch_init(struct mtd_info *mtd)
> >>>>>>>
> >>>>>>> static inline void nand_bch_free(struct nand_bch_control *nbc) {}
> >>>>>>>
> >>>>>>> -#endif /* CONFIG_MTD_NAND_ECC_BCH */
> >>>>>>> +#endif /* CONFIG_MTD_NAND_ECC_SW_BCH */
> >>>>>>>
> >>>>>>> #endif /* __MTD_NAND_BCH_H__ */
> >>>>>>
> >>>>>> Sorry, I didn't look at the right branch, this part of the code was
> >>>>>> correct, but we still have a problem to express the RAW_NAND(y) ->
> >>>>>> SW_BCH(y) dependency.
> >>>>>
> >>>>> It seems this dependency is not always need,
> >>>>>
> >>>>> case MTD_RAW_NAND set to y works well while CONFIG_MTD_NAND_ECC_SW_BCH is not set.
> >>>>
> >>>> Yes, I know, but forcing nand_bch to a be a boolean is not the right
> >>>> solution either, hence my suggestion to use 'imply'.
> >>
> >> Why exactly? SW BCH is going to be converted to the generic ECC engine
> >> abstraction and IIRC you told me that it would not be problematic to
> >> turn it into a boolean?
> >
> > Yes, I told you we should turn it into a boolean and embed the code in
> > the nandcore.o object which can itself be linked as a module or embedded
> > in the kernel image (see above for a version adapted for nand.o). That's
> > not exactly what Yue proposed.
>
> So is there anothor fix or just to pick my v2 ?
>
> https://patchwork.ozlabs.org/patch/1083480/


Looks like someone posted it already:

https://patchwork.ozlabs.org/patch/1083603/