Re: [PATCH] cramfs: fix MTD dependency

[Arnd Bergmann]

On Fri, Nov 10, 2017 at 5:35 PM, Nicolas Pitre <nicolas.pitre@xxxxxxxxxx> wrote:
> On Fri, 10 Nov 2017, Arnd Bergmann wrote:
>
>> With CONFIG_MTD=m and CONFIG_CRAMFS=y, we now get a link failure:
>>
>> fs/cramfs/inode.o: In function `cramfs_mount':
>> inode.c:(.text+0x220): undefined reference to `mount_mtd'
>> fs/cramfs/inode.o: In function `cramfs_mtd_fill_super':
>> inode.c:(.text+0x6d8): undefined reference to `mtd_point'
>> inode.c:(.text+0xae4): undefined reference to `mtd_unpoint'
>>
>> This adds a more specific Kconfig dependency to avoid the
>> broken configuration. Alternatively we could make CRAMFS
>> itself depend on "MTD || !MTD" with a similar result.
>>
>> Fixes: 99c18ce580c6 ("cramfs: direct memory access support")
>> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
>> ---
>>  fs/cramfs/Kconfig | 1 +
>>  1 file changed, 1 insertion(+)
>>
>> diff --git a/fs/cramfs/Kconfig b/fs/cramfs/Kconfig
>> index f937082f3244..58e2fe40b2a0 100644
>> --- a/fs/cramfs/Kconfig
>> +++ b/fs/cramfs/Kconfig
>> @@ -34,6 +34,7 @@ config CRAMFS_BLOCKDEV
>>  config CRAMFS_MTD
>>       bool "Support CramFs image directly mapped in physical memory"
>>       depends on CRAMFS && MTD
>> +     depends on CRAMFS=m || MTD=y
>
> I think the following is better:
>
> diff --git a/fs/cramfs/Kconfig b/fs/cramfs/Kconfig
> index f937082f32..a00740c668 100644
> --- a/fs/cramfs/Kconfig
> +++ b/fs/cramfs/Kconfig
> @@ -33,7 +33,7 @@ config CRAMFS_BLOCKDEV
>
>  config CRAMFS_MTD
>         bool "Support CramFs image directly mapped in physical memory"
> -       depends on CRAMFS && MTD
> +       depends on CRAMFS && (CRAMFS <= MTD)
>         default y if !CRAMFS_BLOCKDEV
>         help
>           This option allows the CramFs driver to load data directly from

I've never seen that syntax, what does it mean?

       Arnd