Environment

Pkg: nerves_toolchain_armv6_nerves_linux_gnueabihf
Vsn: 1.4.3
Type: toolchain
BuildRunner: {Nerves.Artifact.BuildRunners.Local, []}

Pkg: mobile_rpi0
Vsn: 1.17.0
Type: system
BuildRunner: {Nerves.Artifact.BuildRunners.Docker, [make_args: ["source", "all"]]}

Pkg: nerves_system_br
Vsn: 1.17.0
Type: system_platform
BuildRunner: {nil, []}

Pkg: nerves_toolchain_ctng
Vsn: 1.8.4
Type: toolchain_platform
BuildRunner: {nil, []}

Current behavior

I've been wondering how I corrupted an SD card before, and now I found at least one way: with an active deployment running and fwup in progress, but also local performing a fwup via ssh, it looks like the two update processes simultaneously wrote to the "unused" partition, resulting in complete garbage.

As an aside, is the on-disk cecksum not verified on firmware updates?

On rpi0, this lands in an infinite reboot cycle.

Expected behavior

Noticing corruption before reboot.

Companion issue on nerves_hub_link: nerves-hub/nerves_hub_link#98