Re: panic and fs corruption in -current

On 8/5/07, A. Rios <cosasvarias_at_gmail.com> wrote:
>
> I compiled yesterday's kernel without problems, and it restarted fine. I
> applied jeff roberson's ulehtt.diff (P4 with hyperthreading and 2GB RAM
> here)
> and disabled all kernel debugging (I was testing performance)
>
> Earlier this morning I was portupgrading and everything start to fail. One
> of the
> (random) panics was:
>
>
Ok, now I have a kernel with debug symbols and I've found a way to reproduce
the panic. It occurs when installing a port and after the message "SHA256
checksum OK for port XXXXX", at this point the system freezes and sometimes
it dumps the memory and reboot itself, and other times it simply freezes and
I have to restart the computer. I think the problem came from somewhere of
the gcc/make toolchain but I don't know where to start.

Kernel sources was fetched this morning, so the ulehtt patch isn't guilty.
Since I don't have any experience with kgdb I can only follow the steps from
the handbook (I don't know if it has anything to do with the panic, but it
costs nothing to attach :)

/usr/obj/usr/src/sys/7.agosto- 2.debug# kgdb kernel.debug/var/crash/vmcore.4
[GDB will not be able to debug user-mode threads: /usr/lib/libthread_db.so:
Undefined symbol "ps_pglobal_lookup"]
GNU gdb 6.1.1 [FreeBSD]
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain
conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "amd64-marcel-freebsd".

Unread portion of the kernel message buffer:
start = 0, len = 2758, fs = /usr
panic: ffs_alloccg: map corrupted
cpuid = 1
Uptime: 3m50s
Physical memory: 2035 MB
Dumping 434 MB: 419 403 387 371 355 339 323 307 291 275 259 243 227 211 195
179 163 147 131 115 99 83 67 51 35 19 3

#0  doadump () at pcpu.h:194
194             __asm __volatile("movq %%gs:0,%0" : "=r" (td));
(kgdb)