Re: KQUEUE/TTY related panic

From: Robert Watson <rwatson_at_freebsd.org>
Date: Sun, 5 Sep 2004 10:53:51 -0400 (EDT)
On Sun, 5 Sep 2004, Maxim Maximov wrote:

> 	Just got a panic when dropped into DDB by Ctrl-Alt-Esc, issued
> 'show witness', pressed ScrLk, pressed PgUp ten times, then PgDn. Then
> released cursor by pressing ScrLk again. 

This is pretty much identical to the panic Jan Srzednicki reported,
wherein the syscons code under DDB calls into the TTY code (and really
shouldn't).  The low level polled console I/O routines are not supposed to
mess with schedulers, etc, etc.  CC'ing Doug White since he expressed some
interest in all this :-).

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert_at_fledge.watson.org      Principal Research Scientist, McAfee Research


> 
> db> panic: blockable sleep lock (sleep mutex) tty _at_ 
> /usr/src/sys/kern/kern_event.c:1450
> cpuid = 0
> boot() called on cpu#0
> Uptime: 2m22s
> 
> 	Machine freezes completely here. Keys didn't work. Reset helped.
> 	Tried exactly the same actions after reboot - exactly same effect.
> 	Machine is SMP, HTT, WITNESS enabled, today's HEAD.
> 	Dmesg is at http://mcsi.pp.ru/dmesg.boot
> 
> -- 
> Maxim Maximov
> _______________________________________________
> freebsd-current_at_freebsd.org mailing list
> http://lists.freebsd.org/mailman/listinfo/freebsd-current
> To unsubscribe, send any mail to "freebsd-current-unsubscribe_at_freebsd.org"
> 
Received on Sun Sep 05 2004 - 12:56:39 UTC

This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:38:10 UTC