g_disk_done() vs a destroyed disk

[Poul-Henning Kamp]

--------
In message <cba9c9bf-97ad-e3ae-e209-ea91e49b5822 at FreeBSD.org>, Andriy Gapon writes:
>
>I've seen a situation where g_disk_done() was called on a bio after the
>corresponding disk had been already destroyed via g_disk_destroy().
>That call resulted in a crash here:
>	devstat_end_transaction_bio_bt(sc->dp->d_devstat, bp, &now);
>because sc->dp was NULL.
>
>Is it a bug that we do not check for dp being NULL (or dp->d_destroyed being
>set) in g_disk_done() ?
>Or is it a bug that a controller driver called biodone() for that bio having
>earlier called disk_destroy() ?

It is a driver bug to call disk_destroy() before purging all in-flight bios
with biodone()

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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Never attribute to malice what can adequately be explained by incompetence.