On Mon, Nov 08, 2021 at 11:19:35AM -0800, Tadeusz Struk wrote:

I have ran this on the latest mainline. I can confirm that the errors are
nicely handled there. It triggers a warning and panics in device_add_disk()
because of:
return WARN_ON_ONCE(ret); /* keep until all callers handle errors */
and
Kernel panic - not syncing: panic_on_warn set ...

The WARRN_ON will go away once all drivers are fixed.  And no, it does
not panic the kernel unless you set an obscure sysctl asking for it to
panic on warnings, in which case you get what you ask for.