Re: question about crypto module dependency

On Wed, Jan 18, 2012 at 11:25 PM, Herbert Xu
[off-list ref] wrote:

On Wed, Jan 18, 2012 at 02:56:45PM +0100, Francis Moreau wrote:

quoted

What do you mean with "at module init time" ?

My point is:

  $ grep btrfs /lib/modules/3.2.1/modules.dep
  kernel/fs/btrfs/btrfs.ko: kernel/lib/zlib_deflate/zlib_deflate.ko
kernel/lib/libcrc32c.ko

and

  $ grep libcrc32c.ko: /lib/modules/3.2.1-1.1-desktop/modules.dep
  kernel/lib/libcrc32c.ko:

So there's no dependency here to 'pull' a crc32c backend, therefore
"crypto_alloc_shash("crc32c", 0, 0)" used by libcrc32c at load time
fails.

We have a Kconfig dependency and the rest is taken care of by
modprobe.

Hmm could you please be more verbose and details how it's supposed to work ?

How things are supposed to work when :

  - crc32c module is not loaded
  - libcrc32c module is not loaded
  - btrfs is not loaded

and I issue: "modprobe btrfs" ?

Perhaps your problem is really with mkinitramfs?

For now I can't tell, I did describe the issue I'm facing (it's not a
theoritical one) but you still haven't described how this is supposed
to work.

And after reading the code, I don't see how the use case I described
previously can work without some user space tweakings. But should
userpsace stuff have knowledge of such module deps ?

Thanks for your time.
-- 
Francis