panic on shutdown anyone (insmntque())?

[Richard Todd]

On Sat, Sep 06, 2008 at 08:12:43PM +0200, Pawel Jakub Dawidek wrote:
> On Fri, Sep 05, 2008 at 07:01:55PM -0500, Richard Todd wrote:
> > But appears not to fix the panic I've seen trying to boot any kernel since
> > the insmntque patches went in, just at the point where it tries to mount
> > the root FS:
> [...]
> 
> I committed another fix, try now.

Still panics at trying to mount root, but a different panic:

Trying to mount root from zfs:rootpool/tolot-root


Fatal trap 12: page fault while in kernel mode
cpuid = 1; apic id = 01
fault virtual address	= 0x83
fault code		= supervisor read, page not present
instruction pointer	= 0x20:0x80b1d76a
stack pointer	        = 0x28:0x86ce57e8
frame pointer	        = 0x28:0x86ce57fc
code segment		= base 0x0, limit 0xfffff, type 0x1b
			= DPL 0, pres 1, def32 1, gran 1
processor eflags	= interrupt enabled, resume, IOPL = 0
current process		= 1 (kernel)
[thread pid 1 tid 100002 ]
Stopped at      VOP_UNLOCK_APV+0x1a:    cmpl    $0,0x80(%ebx)
db> bt
Tracing pid 1 tid 100002 td 0x870c4d20
VOP_UNLOCK_APV(3,86ce5850,275,0,86ce585c,...) at VOP_UNLOCK_APV+0x1a
zfs_zget(87ae9000,3,0,86ce5950,8,...) at zfs_zget+0x218
zfs_init_fs(87ae9000,86ce5950,8708fd00,87ae9008,2,...) at zfs_init_fs+0x2a0
zfs_mount(87afd9a8,870c4d20,80bc696e,3f4,0,...) at zfs_mount+0x35a
vfs_donmount(20,87a9a970,87a8b540,6,86ce5b78,...) at vfs_donmount+0x13ca
kernel_mount(87a9a970,4001,87b06580,ffffffff,86ce5bc0) at kernel_mount+0x78
kernel_vmount(4001,80bc6c5b,87a9a9a0,80bc6c6a,80bb3dbf,...) at kernel_vmount+0x63
vfs_mountroot_try(80bc6f6d,80bb3dbf,80bab538,1,80864b50,...) at vfs_mountroot_try+0x132
vfs_mountroot(80d0cfb0,4,80bb5119,264,870c2d94,...) at vfs_mountroot+0x423
start_init(0,86ce5d38,80bb6b6d,322,870c2d0c,...) at start_init+0x65
fork_exit(807acb00,0,86ce5d38) at fork_exit+0xb8
fork_trampoline() at fork_trampoline+0x8
--- trap 0, eip = 0, esp = 0x86ce5d70, ebp = 0 ---
db> show registers
cs                0x20
ds          0x86ce0028
es          0x81070028  zvol_get_data+0x1a8
fs                 0x8
ss                0x28
eax                0x3
ecx                0x1
edx         0x870c4d20
ebx                0x3
esp         0x86ce57e8
ebp         0x86ce57fc
esi         0x86ce5850
edi                  0
eip         0x80b1d76a  VOP_UNLOCK_APV+0x1a
efl            0x10206
VOP_UNLOCK_APV+0x1a:    cmpl    $0,0x80(%ebx)
db> reboot

Any suggestions on how to debug this further?