Re: [DistroKit] [PATCH 1/5] v8a: enable initrd generation

[Johannes Zink <j.zink@pengutronix.de>]

Hi Jan,

On 6/6/23 16:59, Jan Lübbe wrote:
> On Tue, 2023-06-06 at 16:44 +0200, Johannes Zink wrote:
>> Hi Ahmad,
>>
>> On 6/6/23 16:37, Ahmad Fatoum wrote:
>>> On 06.06.23 16:31, Johannes Zink wrote:
>>>> also generate rootfs as cpio.gz, as this allows loading it as initramfs.
>>>
>>> You enable both CONFIG_RD_GZIP and CONFIG_RD_ZSTD (which I am fine with),
>>> but you decide here for cpio.gz. Any particular reason?
>>
>> afaik ZSTD support is rather new and I wanted to have maximum flexibility when
>> reusing the initramfs, even with older kernels - i.e. being able to mix a
>> ptxdist-built initramfs with older kernels. I opted to also support zstd, to
>> allow booting future initramfs' on current kernels, should gzip support ever be
>> dropped in the future.
>>
>> However, I think we could probably drop the zstd support, if you are concerned
>> about image size.
> 
> CONFIG_KERNEL_ZSTD is supported since 5.9:
> https://cateee.net/lkddb/web-lkddb/KERNEL_ZSTD.html
> 
> In cases where an old kernel should be booted with this new initramfs, you can
> just recompress it with gz on the host (which is trivial compared to building it
> in the first place).
> 
> I'd suggest just going with zstd only.
> 
> Jan

ack, gonna change support to zstd and drop gz in v2 of this series.

Johannes

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