Subject: Re: Strange lockmgr panic
To: Martin Husemann <martin@duskware.de>
From: Manuel Bouyer <bouyer@antioche.eu.org>
List: current-users
Date: 07/23/2004 19:33:33
On Fri, Jul 23, 2004 at 07:13:26PM +0200, Martin Husemann wrote:
> Has anyone seen something like this?
> 
> I have one machine that does this with some kernels, repeatbly, but works
> fine with others, repeatably as well.
> 
> ...
> Kernelized RAIDframe activated                            
> wd0 at atabus0 drive 0panic: lockmgr: no context
> kdb breakpoint at 11bbfd0                       
> Stopped at      netbsd:cpu_Debugger+0x4:        nop
> db> bt                                             
> lockmgr(18388a8, 0, 0, 3, a, 1860400) at netbsd:lockmgr+0x1ec
> uvmfault_lookup(e0017970, 0, cc0db60, 6, fffffffffffffffc, 0) at netbsd:uvmfault_lookup+0x1b4
> uvm_fault(18388a0, 0, 1, 1, 1809510, 1875080) at netbsd:uvm_fault+0x70
> data_access_fault(e0017b70, 30, 108f004, 0, 50, 800809) at netbsd:data_access_fault+0x418
> ?(11d7400, 0, 331be458, 6, fffffffffffffffb, 1) at 0x100871c

I wonder what could be at 0x100871c

> __wdccommand_done(28681d0, f007a8cc, 54, 12c, 2, 1fe02c00010) at netbsd:__wdccommand_done+0x1b0
> cmd_pci_intr(2868000, 0, e0017ed0, cc0d870, 11964cc, 18750c0) at netbsd:cmd_pci_intr+0xbc
> ...
> 
> This is the only machine doing this to me, and I suspect one of it's
> disks is marginal - but I don't see how that would be related.

__wdccommand_done() can do bus_space_read_1() operations. I guess this
can trigger a fault if the controller or drive fails, i don't know if
this could generate a data_access_fault on i386.

-- 
Manuel Bouyer <bouyer@antioche.eu.org>
     NetBSD: 26 ans d'experience feront toujours la difference
--