if_run and wlan_amrr: kernel panics on 8.2-PRERELEASE amd64

[Bernhard Schmidt]

On Thursday, January 20, 2011 12:46:02 Alexander Zagrebin wrote:
> Hi!
> 
> On 19.01.2011 17:57:00 +0100, Bernhard Schmidt wrote:
> > > > So there is the one issue only: the panic if runfw.ko and
> > > > wlan_amrr.ko both loaded via loader.conf.
> > > > Have you any ideas?
> > > 
> > > No yet, I'll dig around there later today.
> > 
> > Hmm, I'm not able to reproduce this, works as expected. Is this
> > still the same backtrace as the previous error?
> 
> It seems that no. I've recompiled a kernel with the KDB support and
> got this:

Indeed, thanks!

> kernel trap 12 with interrupts disabled
> 
> 
> Fatal trap 12: page fault while in kernel mode
> cpuid = 0; apic id = 00
> fault virtual address   = 0x308
> fault code              = supervisor read data, page not present
> instruction pointer     = 0x20:0xffffffff8030161a
> stack pointer           = 0x28:0xffffffff80b7ec30
> frame pointer           = 0x28:0xffffffff80b7ec60
> code segment            = base 0x0, limit 0xfffff, type 0x1b
>                         = DPL 0, pres 1, long 1, def32 0, gran 1
> processor eflags        = resume, IOPL = 0
> current process         = 0 (swapper)
> trap number             = 12
> panic: page fault
> cpuid = 0
> KDB: stack backtrace:
> #0 0xffffffff8033408e at kdb_backtrace+0x5e
> #1 0xffffffff80303037 at panic+0x187
> #2 0xffffffff804cbbd0 at trap_fatal+0x290
> #3 0xffffffff804cbfaf at trap_pfault+0x28f
> #4 0xffffffff804cc48f at trap+0x3df
> #5 0xffffffff804b4594 at calltrap+0x8
> #6 0xffffffff8041a4e0 at LibAliasAttachHandlers+0x160
> #7 0xffffffff80b71024 at mod_handler+0x14
> #8 0xffffffff802f2318 at module_register_init+0xb8
> #9 0xffffffff802bdc77 at mi_startup+0x77
> #10 0xffffffff80162b3c at btext+0x2c
> Uptime: 1s
> Automatic reboot in 15 seconds - press a key on the console to abort
> --> Press a key on the console to reboot,
> --> or switch off the system now.
> 
> I have an 'alias_pptp_load="YES"' in the loader.conf, so I've
> disabled alias_pptp.ko instead of if_run.ko, runfw.ko or
> wlan_amrr.ko, and the system was successfully booted.
> It's very strange...
> 
> # kgdb kernel.debug
> 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"...
> (kgdb) list *LibAliasAttachHandlers+0x160
> 0xffffffff8041a4e0 is in LibAliasAttachHandlers
> (../../../netinet/libalias/alias_mod.c:84). 79      }
> 80
> 81      static __inline void
> 82      LIBALIAS_WLOCK(void)
> 83      {
> 84              rw_wlock(&handler_rw);
> 85      }
> 86
> 87      static __inline void
> 88      LIBALIAS_WUNLOCK(void)
> (kgdb)
> 
> I understand, that it isn't wlan problem now, but may be you have any
> thoughts?

Honestly, no clue, smells like handler_rw isn't initialized. Does 
loading libalias.ko before alias_pptp.ko make any difference?

-- 
Bernhard