Re: port-arm/55737: Apparent bug in evbarm64 DMA code causes filesystem corruption

[Richard Todd <rmtodd%servalan.servalan.com@localhost>]

Nick Hudson <nick.hudson%gmx.co.uk@localhost> writes:
>
> I think this patch is correct and covers the case that your patch
> doesn't where there are no ranges in the parent tag.
>
> I think the virtio patch is still valid, however.

Okay, here's the (somewhat delayed) results from my testing that I
promised earlier. 

1) The virtio patch you provided earlier (here 
http://mail-index.netbsd.org/port-arm/2020/10/19/msg007017.html)
seems to do the trick -- applying that to a recentish -current tree
(21a63fef3aab date:        Mon Oct 19 09:07:29 2020 +0000, if it matters)
resulted in a kernel that could withstand three rounds of
sysupgrade installing kernel and world without a single panic.  So that
patch looks good.

2) The patch you just gave for bus_dma.c, applied by itself on top of
the same -current, does *not* seem to fix the problem; we get what looks
like the same panic at about the same place.