cvs commit: src/sys/dev/pccbb pccbb.c

[M. Warner Losh]

In message: <443E7B68.50807 at errno.com>
            Sam Leffler <sam at errno.com> writes:
: M. Warner Losh wrote:
: > In message: <20060412212843.GH1258 at haakonia.hitnet.RWTH-Aachen.DE>
: >             Christian Brueffer <brueffer at FreeBSD.org> writes:
: > : On Thu, Mar 30, 2006 at 04:25:45AM +0000, Warner Losh wrote:
: > : > imp         2006-03-30 04:25:45 UTC
: > : > 
: > : >   FreeBSD src repository
: > : > 
: > : >   Modified files:
: > : >     sys/dev/pccbb        pccbb.c 
: > : >   Log:
: > : >   On some laptops, under very high loads, the socket event register read
: > : >   in the ISR doesn't read the actual socket event register, but instead
: > : >   reads garbage (usually 0xffffffff, but other times other things).
: > : >   This totally violates the PCI spec, but happens rarely enough that a
: > : >   workaround is in order.  This adds one test when we have a real
: > : >   interrupt to service (which is very rare), and doesn't affect the
: > : >   usualy 'nothing to see here' case at all.
: > : >   
: > : >   Problem reported by many, but sam@ gave me this workaround after
: > : >   diagnosing the problem.
: > : >   
: > : 
: > : This breaks pccard/cardbus support on my Thinkpad T41p (confirmed by
: > : backing this change out).  With this change, I just get an "Interrupt
: > : storm detected on irq 5; throttling" message.
: > : 
: > : What kind of debug info can I provide?
: > 
: > A Thinkpad T41p. :-)
: > 
: > Failing that, can you set hw.cbb.debug=1 and provide me with the
: > output.
: 
: We should just back this out until we can resolve the issue.  For other 
: folks: the change was originally done for an hp nx6125 laptop where 
: running a wireless card in monitor mode would cause spontaneous 
: interface detach's under load.  It sounds like the root cause is elsewhere.

OK.

Warner