Subject: kern/27597: 2.0: Scheduler Activations related panic
To: None <gnats-bugs@gnats.netbsd.org>
From: Hubert Feyrer <feyrer@rfhpc8323.fh-regensburg.de>
List: netbsd-bugs
Date: 10/28/2004 12:16:56
>Number: 27597
>Category: kern
>Synopsis: 2.0: Scheduler Activations related panic
>Confidential: no
>Severity: critical
>Priority: high
>Responsible: kern-bug-people
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: sw-bug
>Submitter-Id: net
>Arrival-Date: Thu Oct 28 10:18:00 UTC 2004
>Closed-Date:
>Last-Modified:
>Originator: Hubert Feyrer
>Release: NetBSD 2.0_RC4
>Organization:
Hubert Feyrer <hubertf@channel.regensburg.org>
>Environment:
System: NetBSD miyu 2.0_RC2 NetBSD 2.0_RC2 (MIYU) #19: Sat Oct 2 00:58:46 MEST 2004 feyrer@miyu:/home/cvs/src-2.0/sys/arch/i386/compile/obj.i386/MIYU i386
Architecture: i386
Machine: i386
>Description:
For a few days, I've seen several complete halts of the system while
under little load, with X freezing, and not even (blindly typed)
ctl+alt+esc followed by "r" helped getting out.
Leaving the system sit on the console for some time, I saw
a panic about a failed assertion in line 1044 of kern_sa.c
(sorry, no verbatim output), and I was able to force a crashdump
via ctl+alt+esc. The crashdump says:
(gdb) target kcore netbsd.7.core
panic: kernel %sassertion "%s" failed: file "%s", line %d
#0 0x0fef0000 in ?? ()
(gdb)
Line 1044 of kern_sa.c says (rev. 1.50.1.2):
KDASSERT(vp->savp_lwp == l2);
(which is also what was in the panic message).
Stack trace just shows action from after ctl+alt+esc:
(gdb) bt
#0 0x0fef0000 in ?? ()
#1 0xc02bb6e7 in cpu_reboot ()
#2 0xc0201339 in db_reboot_cmd ()
#3 0xc0200e7f in db_command ()
#4 0xc0200b92 in db_command_loop ()
#5 0xc0203c5c in db_trap ()
#6 0xc02b8e52 in kdb_trap ()
#7 0xc02c5ff4 in trap ()
#8 0xc0102e01 in calltrap ()
#9 0xc0307b90 in internal_command ()
#10 0xc0307db5 in wskbd_translate ()
#11 0xc0306c1f in wskbd_input ()
#12 0xc030bcfb in pckbd_input ()
#13 0xc030b6d2 in pckbportintr ()
#14 0xc0170614 in pckbcintr ()
>How-To-Repeat:
Run fvwm, gqmpeg, a system or pkgsrc build in the background,
TeX - and see the system freeze all of a sudden.
>Fix:
Aparently the condition can arise that vp->sav_lwp is not equal to
l2. Dunno where to go from there.
>Release-Note:
>Audit-Trail:
>Unformatted: