Bug#872999: qemu image built by vmdebootstrap is unbootable due to bad root=/dev/mapper/loop0p1 kernel parameter

[Raphael Hertzog]

On Thu, 07 Sep 2017, Raphael Hertzog wrote:
> Is there anything that can be done by vmdebootstrap to force-trigger the
> creation of that entry even when chrooted?

Yes, "udevadm trigger" or "udevadm trigger /dev/mapper/loop0p1" works
well for that. So we have a work-around at least (thanks to Felipe Sateler
for the suggestion, thanks also to Mantas Mikulėnas who taught me about
the kernel/udev interactions).

But I'm clearly not able to go further than that, debugging the kernel
would be too time-consuming for me since I'm not a kernel developer...
so I'll stop my investigations here.

(Somehow I wonder whether this is not the result of some kernel
hardening... limiting the impact of things done within a chroot
compared to the main host. schroot also uses private bind mounts, can this
be related?)

Cheers,
-- 
Raphaël Hertzog ◈ Debian Developer

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