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Subject: Re: [PATCH v4 1/2] Provide in-kernel headers for making it easy to
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To:     Joel Fernandes <joel@joelfernandes.org>,
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From:   "Enrico Weigelt, metux IT consult" <lkml@metux.net>
Organization: metux IT consult
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Date:   Fri, 8 Mar 2019 14:57:24 +0100
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On 08.03.19 14:42, Joel Fernandes wrote:

Hi folks,

> That sounds like it could be useful. I don't see any reason off the
> top why that would not be possible to add to the list of archived
> files in the future. The patch allows populating the list of files
> from Kbuild using ikh_file_list variable.

It seems the whole thing's going into a direction where a whole own
subtopic is coming up: compressed built-in filesystem.

Haven't had a deeper thought about it yet, whether or not existing
filesystems like squashfs, initramfs, etc are the right thing for that,
or something new should be invented, but a generic mechanism for
compiled-in compressed (ro) filesystems could also be interesting
for very small devices, that perhaps even dont need any persistence.

Some requirements coming up in mind:

1. it shall be possible to have any number of instances - possibly by
   separate modules.
2. it shall be possible to use an bootloader/firmware provided image
   (so it can serve as initrd)
2. data should stay compressed as long as possible, but uncompressed
   data might be cached - do decompression on-demand
3. only needs to be ro (write access could be done via unionfs+friends)
4. it shall be swappable (if swap is enabled)

In that scenario, these in-kernel headers would just one consumer,
I can imagine lots of others.


--mtx

-- 
Enrico Weigelt, metux IT consult
Free software and Linux embedded engineering
info@metux.net -- +49-151-27565287