Re: On softints, softnet_lock and sleeping (aka ipv6 vs USB network interfaces)

[Nick Hudson <skrll%netbsd.org@localhost>]

On 01/01/16 15:21, Frank Kardel wrote:
> Hi !
>
> Is there any progress on this? I see also PR/49065 being still 
> existent on an RPI2.
> Also running named with 4 threads on an RPI2 together with vtund doing 
> "ifconfig tunX ..."
> is a sure killer. Runinng named with only one thread gets you over it 
> (maybe just most of the time).

You might like to try

     http://www.netbsd.org/~skrll/usb.softint.diff

as fixing everything to not hold softnet_lock while doing USB transfers 
is a lot of
work.  The patch should help in the meantime and is probably correct 
regardless.

Changing the USB callbacks to run at IPL_SOFTSERIAL really means that the
USB callbacks should be re-checked that they provide the right protection
when calling into the subsystems they access.

Let me know if the patch fixes things for you.

Thanks,
Nick