CFT: vr(4)

Milan Obuch freebsd-current at
Sun Feb 17 14:17:41 UTC 2008

On Sunday 17 February 2008, Milan Obuch wrote:
> On Sunday 17 February 2008, Robert Watson wrote:
> > On Sat, 16 Feb 2008, Milan Obuch wrote:
> > >> I have tested 4-port Rhine III(6105LOM) and I never seen this hangs.
> > >> Does this also happen on other network interface too? When the system
> > >> hangs, would you break into DDB and show me the output of 'show
> > >> alllocks' and 'ps'?
> > >
> > > I need some tests with another box. I was not able to break into DDB.
> > > Ctrl-Alt-Esc worked until hang. Hang was really hard, Ctrl-Alt-Esc did
> > > not invoke DDB. I do not feel if_vr is culprit here, more probably PCI
> > > bus got somehow locked, but I have no idea how could I test it
> > > currently.
> >
> > FYI, there are known issues with the effectiveness of syscons
> > ctrl-alt-esc to get into the debugger -- if you haven't tried with a
> > serial break on a serial console, you might want to do so.  This is
> > because syscons's interrupt handler acquires the Giant lock in an
> > ithread, requiring a lot more things to be happy to succeed.  In
> > constrast, sio (and friends) use fast interrupt handlers and no Giant
> > lock on the way to processing the break request.  It may well be that a
> > serial break doesn't get into DDB for you, but it's worth trying...
> >
> > Robert N M Watson
> > Computer Laboratory
> > University of Cambridge
> You are right, after rebuilding kernel with BREAK_TO_DEBUGGER I am able to
> get requested data. BTW, I can't find just now what ALT_BREAK_TO_DEBUGGER
> means...
> After kldload if_vr, dhclient vr0 and ping -f <someaddress> in a minute
> system freezes.

Correction... as I moved cable from on-board re0 to vr0, system remembered arp 
table entry and did not actually try to use vr0. Now I repeated it, but boot 
system with cable in vr0. This time it hangs right after ping <>, and break 
does not enter debugger... hard hang. I tried it twice, the same result...

So no data to check, actually, only hard hang.


Address this mail is sent from is used only for this mailing list.
Do not send any messages to it directly as a response, reply only
to mailing list. For mail to me personally, use milan in address instead.

More information about the freebsd-current mailing list