[Buildroot] [PATCH 1/2] configs/stm32mp157c_dk2: disable mkfs metadata_csum and dir_index options

[Bartosz Bilas]

Hello guys,

On 17.11.2019 20:31, Arnout Vandecappelle wrote:
>
> On 09/11/2019 16:25, Bartosz Bilas wrote:
>> Hello Thomas,
>>
>> On 09.11.2019 15:22, Thomas Petazzoni wrote:
>>> Hello Bartosz,
>>>
>>> On Sun,  3 Nov 2019 12:50:16 +0100
>>> Bartosz Bilas <b.bilas at grinn-global.com> wrote:
>>>
>>>> To solve issue with non-possibilities to mount rootfs partition we
>>>> should disable a new mkfs features such as metadata_csum and
>>>> dir_index because there is incompatibility with these options.
>>>>
>>>> Signed-off-by: Bartosz Bilas <b.bilas at grinn-global.com>
>>>> ---
>>>>    configs/stm32mp157c_dk2_defconfig | 1 +
>>>>    1 file changed, 1 insertion(+)
>>>>
>>>> diff --git a/configs/stm32mp157c_dk2_defconfig
>>>> b/configs/stm32mp157c_dk2_defconfig
>>>> index a1e61d752d..ba044e5e55 100644
>>>> --- a/configs/stm32mp157c_dk2_defconfig
>>>> +++ b/configs/stm32mp157c_dk2_defconfig
>>>> @@ -16,6 +16,7 @@ BR2_LINUX_KERNEL_INSTALL_TARGET=y
>>>>    BR2_TARGET_ROOTFS_EXT2=y
>>>>    BR2_TARGET_ROOTFS_EXT2_4=y
>>>>    BR2_TARGET_ROOTFS_EXT2_SIZE="120M"
>>>> +BR2_TARGET_ROOTFS_EXT2_MKFS_OPTIONS="-O ^64bit,^metadata_csum,^dir_index"
>>> Are you sure it is necessary to disable those three options?
>>>
>>> Indeed, U-Boot ext4 write support clearly excludes filesystems that
>>> have the metadata_csum option enabled:
>>>
>>>     https://gitlab.denx.de/u-boot/u-boot/blob/master/fs/ext4/ext4_write.c#L880
>>> However, there's nothing about the 64bit and dir_index options. How did
>>> you conclude that they were causing problems? Did you try with just -O
>>> ^metadata_csum ?
>> I was talking with the maintainer of that board on U-Boot mailing list [1] and
>> he said that I should disable those 2 options (dir_index and metada_csum) to
>> have U-Boot working properly. I'm not sure about 64bit because I saw that was
>> set by default in buildroot. I didn't check that with metadata_csum option only
>> but I'll do that and let you know if it works.
>   As explained in the help text of the option:
>
>            The default is "-O ^64bit", i.e. disable 64-bit filesystem
>            support. This default value has been chosen because U-Boot
>            versions before 2017.02 don't support this filesystem
>            option: using it may make the filesystem unreadable by
>            U-Boot.
>
>   Since this defconfig uses a more recent U-Boot, it's not necessary.
>
>   That said, if those two options should be disabled for U-Boot to work, it's
> probably a good idea to add them to the defaults (i.e. all three options, like
> you put in the defconfig here).
I've checked if it worked with disabled metadata_csum option only and it 
turns out that Thomas is right. Kernel is able to mount rootfs partition 
properly even if I do any environment operation in U-Boot. So it means 
that the default 64bit option is not necessary as well.
>
>   Regards,
>   Arnout
>
>
>
>   Regards,
>   Arnout
Best
Bartek