Bug#928775: debootstrap: Misleading error message on read-only /

[Uwe Kleine-König <u.kleine-koenig@pengutronix.de>]

Package: debootstrap
Version: 1.0.114
Severity: minor

Hello,

I used deboostrap with --arch=armhf --foreign, then booted a system with
the resulting rootfs. The rootfs was mounted read-only. Then starting
the second stage looks as follows:

	I have no name!@192:/# /debootstrap/debootstrap --second-stage
	mknod: //test-dev-null: Read-only file system
	E: Cannot install into target '/' mounted with noexec or nodev
	I have no name!@192:/# mount -o remount,rw / /
	I have no name!@192:/# /debootstrap/debootstrap --second-stage
	I: Installing core packages...
	...

While the message from mknod is right, the one from deboostrap is not.
Maybe this can be improved to also mention read-only rootfs as possible
error? (It could even test which of the three is the actual problem.)

Best regards
Uwe

-- System Information:
Debian Release: buster/sid
  APT prefers testing
  APT policy: (990, 'testing'), (500, 'unstable-debug'), (500, 'testing-debug'), (500, 'stable-updates'), (500, 'stable-debug'), (500, 'unstable'), (500, 'stable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.20.13-ptx (SMP w/24 CPU cores)
Kernel taint flags: TAINT_UNSIGNED_MODULE
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8) (ignored: LC_ALL set to en_US.UTF-8), LANGUAGE=en_US:en (charmap=UTF-8) (ignored: LC_ALL set to en_US.UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages debootstrap depends on:
ii  wget  1.20.1-1

Versions of packages debootstrap recommends:
pn  arch-test               <none>
ii  debian-archive-keyring  2018.1
ii  gnupg                   2.2.12-1

Versions of packages debootstrap suggests:
pn  squid-deb-proxy-client  <none>
pn  ubuntu-archive-keyring  <none>

-- no debconf information