Kernel panic on boot at dm_crypt

[Sepherosa Ziehau]

On Wed, Jul 6, 2016 at 5:54 AM, Stefan Unterweger
<232.20711 at chiffre.aleturo.com> wrote:
> Yet another problem on the same virtualised host as in the other thread
> a few weeks back.
>
> As before, this is a presumably KVM virtualised host.  With the
> exception of a small boot partition, all storage volumes are encrypted
> via cryptsetup‘s LUKS mode.
>
> It looks like a race condition of some weird sort, and there’s no doubt
> that the virtualisation is again playing tricks with me.  If I type in
> the password incorrectly, then it will most likely crash violently right
> there.  If typed in correctly, then in one of five it -might- boot.  The
> kernel panic is attached below.

It looks like a race between the dm init and the I/O path.  i.e. the
read happens even before the dm init is completed.  Not sure about
why...

Thanks,
sephe