[uml-devel] Kernel mode fault at addr 0x92c00000, ip 0x80bcead

[uml-devel] Kernel mode fault at addr 0x92c00000, ip 0x80bcead

[Christopher S. Aker]

This is 2.6.18-um, on top of a 2.6.16.29-skas3-v8.2 host.

Kernel file is here:
http://www.theshore.net/~caker/uml/kernels/2.6.18-linode25


Kernel panic - not syncing: Kernel mode fault at addr 0x92c00000, ip 
0x80bcead

EIP: 0073:[<080bcead>] CPU: 0 Not tainted ESP: 007b:bf55b798 EFLAGS: 
00200246
     Not tainted
EAX: ffffffda EBX: 00000003 ECX: 40118003 EDX: 000fa718
ESI: 40118003 EDI: 4021271b EBP: bf55b7d8 DS: 007b ES: 007b
85a0f2f8:  [<800519a0>] notifier_call_chain+0x2a/0x40
85a0f314:  [<8003ef57>] panic+0x70/0x102
85a0f32c:  [<8001eb96>] segv+0x29d/0x2cb
85a0f35c:  [<80058df6>] autoremove_wake_function+0x2f/0x57
85a0f368:  [<8007f636>] kmem_cache_free+0x54/0xdc
85a0f384:  [<8004c62d>] __mod_timer+0x75/0xb3
85a0f3f8:  [<8001e8ba>] segv_handler+0xa5/0xe4
85a0f41c:  [<8001e815>] segv_handler+0x0/0xe4
85a0f420:  [<80034abc>] sig_handler_common_skas+0x94/0xe5
85a0f444:  [<80030bdd>] sig_handler+0x5d/0x68
85a0f45c:  [<8039a828>] __restore+0x0/0x8
85a0f49c:  [<800350cf>] csum_partial+0xdb/0xe8
85a0f4bc:  [<80062d52>] handle_IRQ_event+0x45/0x69
85a0f4d8:  [<802585d3>] rb_erase+0x5b/0x102
85a0f4e8:  [<8007f636>] kmem_cache_free+0x54/0xdc
85a0f4f0:  [<8004c593>] lock_timer_base+0x2a/0x4f
85a0f504:  [<8004c62d>] __mod_timer+0x75/0xb3
85a0f510:  [<8024f14c>] as_can_break_anticipation+0xef/0x182
85a0f524:  [<8024eb7c>] as_antic_waitnext+0x29/0x68
85a0f530:  [<8024f206>] as_can_anticipate+0x27/0x37
85a0f53c:  [<8024fab4>] as_dispatch_request+0x2f4/0x378
85a0f548:  [<80261c6c>] __add_entropy_words+0x74/0x174
85a0f564:  [<8024594b>] elv_next_request+0x45/0x156
85a0f570:  [<80068274>] mempool_free+0x83/0x93
85a0f584:  [<8002a9de>] do_ubd_request+0x2b/0xbd
85a0f5a0:  [<8001a1ce>] find_irq_by_fd+0x53/0x83
85a0f5a8:  [<80030b12>] maybe_sigio_broken+0x1a/0x58
85a0f5c4:  [<8003a6bc>] __activate_task+0x27/0x3f
85a0f5e8:  [<8003a6bc>] __activate_task+0x27/0x3f
85a0f600:  [<8003a7f7>] activate_task+0x6e/0x7b
85a0f614:  [<800466cc>] local_bh_enable+0x8/0xa9
85a0f624:  [<8003a8d6>] try_to_wake_up+0x90/0xa5
85a0f638:  [<80327340>] ipt_do_table+0x248/0x323
85a0f640:  [<800466cc>] local_bh_enable+0x8/0xa9
85a0f648:  [<80058df6>] autoremove_wake_function+0x2f/0x57
85a0f670:  [<803291a5>] ip_nat_fn+0x7b/0x1e7
85a0f684:  [<802e1607>] ip_local_deliver_finish+0x0/0x1ef
85a0f688:  [<80328b03>] ipt_hook+0x37/0x3b
85a0f6a4:  [<802d8569>] nf_iterate+0x63/0x7b
85a0f6b8:  [<802fe15e>] tcp_v4_rcv+0x4ce/0x8c5
85a0f6c8:  [<802e1607>] ip_local_deliver_finish+0x0/0x1ef
85a0f718:  [<80030fc0>] set_signals+0x1c/0x28
85a0f720:  [<800466cc>] local_bh_enable+0x8/0xa9
85a0f724:  [<8004c62d>] __mod_timer+0x75/0xb3
85a0f738:  [<80030fc0>] set_signals+0x1c/0x28
85a0f74c:  [<802aafe2>] skb_checksum+0xe7/0x28f
85a0f75c:  [<802aa2ce>] pskb_expand_head+0xdc/0x15f
85a0f788:  [<802afd31>] skb_checksum_help+0x9c/0x13e
85a0f7ac:  [<803292fc>] ip_nat_fn+0x1d2/0x1e7
85a0f7dc:  [<802e6c72>] dst_output+0x0/0x14
85a0f7e0:  [<80329528>] ip_nat_local_fn+0x75/0xf3
85a0f7f4:  [<802e6c72>] dst_output+0x0/0x14
85a0f804:  [<802e6c72>] dst_output+0x0/0x14
85a0f808:  [<802d8569>] nf_iterate+0x63/0x7b
85a0f81c:  [<802e6c72>] dst_output+0x0/0x14
85a0f82c:  [<802e6c72>] dst_output+0x0/0x14
85a0f830:  [<802d85ec>] nf_hook_slow+0x6b/0xe4
85a0f84c:  [<802e6c72>] dst_output+0x0/0x14
85a0f86c:  [<802e4a44>] ip_queue_xmit+0x3d7/0x4c2
85a0f884:  [<802e6c72>] dst_output+0x0/0x14
85a0f88c:  [<800327ac>] setjmp_wrapper+0x5c/0x60
85a0f8b0:  [<80032778>] setjmp_wrapper+0x28/0x60
85a0f8ec:  [<8007f413>] kmem_cache_alloc+0x3b/0x5d
85a0f914:  [<8006942b>] buffered_rmqueue+0xa2/0x11a
85a0f944:  [<802f7668>] tcp_transmit_skb+0x2b8/0x4b1
85a0f964:  [<802f83f5>] tcp_snd_test+0x33/0xf4
85a0f984:  [<802f91fd>] tcp_push_one+0xde/0x159
85a0f9ac:  [<802eca55>] tcp_sendmsg+0x438/0xe54
85a0fa0c:  [<80032778>] setjmp_wrapper+0x28/0x60
85a0fa30:  [<8030a718>] inet_sendmsg+0x4a/0x56
85a0fa48:  [<802a4aad>] do_sock_write+0xbb/0xc5
85a0fa6c:  [<802a4c5f>] sock_aio_write+0x95/0x99
85a0fae0:  [<80082978>] do_sync_write+0xde/0x124
85a0fb00:  [<800347c6>] switch_threads+0x61/0x6e
85a0fb3c:  [<80058dc7>] autoremove_wake_function+0x0/0x57
85a0fb5c:  [<8002311f>] buffer_op+0x47/0x77
85a0fb60:  [<80022f86>] do_buffer_op+0x0/0x152
85a0fb90:  [<80082b81>] vfs_write+0x1c3/0x23d
85a0fbc8:  [<80082ccc>] sys_write+0x51/0x80
85a0fbf0:  [<80022bda>] handle_syscall+0x11a/0x138
85a0fc58:  [<80032eed>] move_registers+0x4c/0x66
85a0fc6c:  [<80033b68>] handle_trap+0x31/0x12d
85a0fc74:  [<80032f47>] save_registers+0x40/0x6c
85a0fc94:  [<80034192>] userspace+0x1c7/0x21e
85a0fcf0:  [<80022808>] fork_handler+0xef/0xff
85a0fd1c:  [<8039a828>] __restore+0x0/0x8
85a0fd5c:  [<8039aa81>] kill+0x11/0x20

Is this a UML issue?

-Chris


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Re: [uml-devel] Kernel mode fault at addr 0x92c00000, ip 0x80bcead

[Jeff Dike]

On Tue, Oct 10, 2006 at 06:17:06PM -0500, Christopher S. Aker wrote:
> This is 2.6.18-um, on top of a 2.6.16.29-skas3-v8.2 host.
> 
> Kernel file is here:
> http://www.theshore.net/~caker/uml/kernels/2.6.18-linode25
> 
> 
> Kernel panic - not syncing: Kernel mode fault at addr 0x92c00000, ip 
> 0x80bcead

The stack I get from that is:

85a0f49c:  [<800350cf>] csum_partial+0xdb/0xe8
85a0f74c:  [<802aafe2>] skb_checksum+0xe7/0x28f
85a0f788:  [<802afd31>] skb_checksum_help+0x9c/0x13e
85a0f7ac:  [<803292fc>] ip_nat_fn+0x1d2/0x1e7
85a0f7e0:  [<80329528>] ip_nat_local_fn+0x75/0xf3
85a0f808:  [<802d8569>] nf_iterate+0x63/0x7b
85a0f830:  [<802d85ec>] nf_hook_slow+0x6b/0xe4
85a0f86c:  [<802e4a44>] ip_queue_xmit+0x3d7/0x4c2
85a0f944:  [<802f7668>] tcp_transmit_skb+0x2b8/0x4b1
85a0f984:  [<802f91fd>] tcp_push_one+0xde/0x159
85a0f9ac:  [<802eca55>] tcp_sendmsg+0x438/0xe54
85a0fa30:  [<8030a718>] inet_sendmsg+0x4a/0x56
			__sock_sendmsg
85a0fa48:  [<802a4aad>] do_sock_write+0xbb/0xc5
85a0fa6c:  [<802a4c5f>] sock_aio_write+0x95/0x99
85a0fae0:  [<80082978>] do_sync_write+0xde/0x124
85a0fb90:  [<80082b81>] vfs_write+0x1c3/0x23d
85a0fbc8:  [<80082ccc>] sys_write+0x51/0x80
85a0fbf0:  [<80022bda>] handle_syscall+0x11a/0x138
85a0fc6c:  [<80033b68>] handle_trap+0x31/0x12d
85a0fc94:  [<80034192>] userspace+0x1c7/0x21e
85a0fcf0:  [<80022808>] fork_handler+0xef/0xff
85a0fd1c:  [<8039a828>] __restore+0x0/0x8
85a0fd5c:  [<8039aa81>] kill+0x11/0x20

> Is this a UML issue?

Hard to say.  With a kernel fault, I'd be tempted to say so, but I see no
UML code on the stack.

Have you seen just this one occurence of this?  I spent part of the
afternoon dusting off a patch which would provide the registers at the
time of the segfault.  That maybe would have helped here.

				Jeff

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Re: [uml-devel] Kernel mode fault at addr 0x92c00000, ip 0x80bcead

[Blaisorblade]

On Friday 13 October 2006 22:07, Jeff Dike wrote:
> On Tue, Oct 10, 2006 at 06:17:06PM -0500, Christopher S. Aker wrote:
> > This is 2.6.18-um, on top of a 2.6.16.29-skas3-v8.2 host.
> >
> > Kernel file is here:
> > http://www.theshore.net/~caker/uml/kernels/2.6.18-linode25
> >
> >
> > Kernel panic - not syncing: Kernel mode fault at addr 0x92c00000, ip
> > 0x80bcead
Jeff, are these addresses normal? They tell that the binary is a statically 
linked one - but what is the memory layout? Chris, can you post 
cat /proc/<pid>/maps on a running instance of that kernel, together with host 
and guest config (the guest's one is contained there, I know, but I don't 
have the time to extract).

I'm suspiscious about memory layout problems (say host with unusual splits, 
like 1G/3G, or some problem with memory mappings anyhow).

> The stack I get from that is:
I.e. all the rest are bogus functions?

There are automated solutions for this - compiling with frame pointers allows 
correct backtracing with a runtime penalty but is implemented; however, we 
could reuse (not copy, please, we cannot maintain it) the x86 DWARF unwinder 
(instead of using frame pointer and to slow down fast paths, additional 
out-of-line debug info are used when the stack trace is output) - but we 
should implement this latter one. Jeff, can you take a look at it?

> 85a0f49c:  [<800350cf>] csum_partial+0xdb/0xe8
> 85a0f74c:  [<802aafe2>] skb_checksum+0xe7/0x28f
> 85a0f788:  [<802afd31>] skb_checksum_help+0x9c/0x13e
> 85a0f7ac:  [<803292fc>] ip_nat_fn+0x1d2/0x1e7
> 85a0f7e0:  [<80329528>] ip_nat_local_fn+0x75/0xf3
> 85a0f808:  [<802d8569>] nf_iterate+0x63/0x7b
> 85a0f830:  [<802d85ec>] nf_hook_slow+0x6b/0xe4
> 85a0f86c:  [<802e4a44>] ip_queue_xmit+0x3d7/0x4c2
> 85a0f944:  [<802f7668>] tcp_transmit_skb+0x2b8/0x4b1
> 85a0f984:  [<802f91fd>] tcp_push_one+0xde/0x159
> 85a0f9ac:  [<802eca55>] tcp_sendmsg+0x438/0xe54
> 85a0fa30:  [<8030a718>] inet_sendmsg+0x4a/0x56
> 			__sock_sendmsg
> 85a0fa48:  [<802a4aad>] do_sock_write+0xbb/0xc5
> 85a0fa6c:  [<802a4c5f>] sock_aio_write+0x95/0x99
> 85a0fae0:  [<80082978>] do_sync_write+0xde/0x124
> 85a0fb90:  [<80082b81>] vfs_write+0x1c3/0x23d
> 85a0fbc8:  [<80082ccc>] sys_write+0x51/0x80
> 85a0fbf0:  [<80022bda>] handle_syscall+0x11a/0x138
> 85a0fc6c:  [<80033b68>] handle_trap+0x31/0x12d
> 85a0fc94:  [<80034192>] userspace+0x1c7/0x21e
> 85a0fcf0:  [<80022808>] fork_handler+0xef/0xff
> 85a0fd1c:  [<8039a828>] __restore+0x0/0x8
> 85a0fd5c:  [<8039aa81>] kill+0x11/0x20

-- 
Inform me of my mistakes, so I can keep imitating Homer Simpson's "Doh!".
Paolo Giarrusso, aka Blaisorblade
http://www.user-mode-linux.org/~blaisorblade
Chiacchiera con i tuoi amici in tempo reale! 
 http://it.yahoo.com/mail_it/foot/*http://it.messenger.yahoo.com 


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Re: [uml-devel] Kernel mode fault at addr 0x92c00000, ip 0x80bcead

[Christopher S. Aker]

Blaisorblade wrote:
> On Friday 13 October 2006 22:07, Jeff Dike wrote:
>> On Tue, Oct 10, 2006 at 06:17:06PM -0500, Christopher S. Aker wrote:
>>> This is 2.6.18-um, on top of a 2.6.16.29-skas3-v8.2 host.
>>>
>>> Kernel file is here:
>>> http://www.theshore.net/~caker/uml/kernels/2.6.18-linode25
>>>
>>>
>>> Kernel panic - not syncing: Kernel mode fault at addr 0x92c00000, ip
>>> 0x80bcead
> Jeff, are these addresses normal? They tell that the binary is a statically 
> linked one - but what is the memory layout? Chris, can you post 
> cat /proc/<pid>/maps on a running instance of that kernel, together with host 
> and guest config (the guest's one is contained there, I know, but I don't 
> have the time to extract).
> 
> I'm suspiscious about memory layout problems (say host with unusual splits, 
> like 1G/3G, or some problem with memory mappings anyhow).

All the stuff you requested is in here: 
http://www.theshore.net/~caker/uml/kmf/

http://www.theshore.net/~caker/uml/kmf/maps.txt (has the maps from all 
the UML's pids, in case you notice duplicates)

http://www.theshore.net/~caker/uml/kmf/config-2.6.18-um.txt
http://www.theshore.net/~caker/uml/kmf/config-2.6.16.29-1-bigmem-skas-v8.2.txt

Thanks!
-Chris


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Re: [uml-devel] Kernel mode fault at addr 0x92c00000, ip 0x80bcead

[Blaisorblade]

On Saturday 14 October 2006 03:19, Christopher S. Aker wrote:
> Blaisorblade wrote:
> > On Friday 13 October 2006 22:07, Jeff Dike wrote:
> >> On Tue, Oct 10, 2006 at 06:17:06PM -0500, Christopher S. Aker wrote:
> >>> This is 2.6.18-um, on top of a 2.6.16.29-skas3-v8.2 host.
> >>>
> >>> Kernel file is here:
> >>> http://www.theshore.net/~caker/uml/kernels/2.6.18-linode25
> >>>
> >>>
> >>> Kernel panic - not syncing: Kernel mode fault at addr 0x92c00000, ip
> >>> 0x80bcead

> > Jeff, are these addresses normal? They tell that the binary is a
> > statically linked one - but what is the memory layout? Chris, can you
> > post
> > cat /proc/<pid>/maps on a running instance of that kernel, together with
> > host and guest config (the guest's one is contained there, I know, but I
> > don't have the time to extract).

> > I'm suspiscious about memory layout problems (say host with unusual
> > splits, like 1G/3G, or some problem with memory mappings anyhow).

> All the stuff you requested is in here:
> http://www.theshore.net/~caker/uml/kmf/

> http://www.theshore.net/~caker/uml/kmf/maps.txt (has the maps from all
> the UML's pids, in case you notice duplicates)

> http://www.theshore.net/~caker/uml/kmf/config-2.6.18-um.txt
> http://www.theshore.net/~caker/uml/kmf/config-2.6.16.29-1-bigmem-skas-v8.2.
>txt
Which is the cmd line? With how much memory where these instances started?

Ok, Jeff, I recall something but I'm not sure. I even thought kernel threads 
mapped the whole RAM at boot in their physical range part (which is their 
entire address space), but it does not seem so.

The host is just a 64G with 3G/1G split, however the UML is a TT+SKAS with 
HALF_GIGS=2 (which _is_ unusual, and could be replaced with disabling TT 
entirely, which gives a free 2,75G of memory space for UML). In fact, the UML 
binary starts at 0x8000 0000 (i.e. 2G), and there are various holes in the 
virtual RAM mapped in kernel side - a big part of about 30M (the 
0x80607000-0x92c00000 range), then there is a 4M hole (the pre-vmalloc hole 
should be 8M, but we have a 4M hole for uml_reserved after current brk()), 
then various holes and allocated ranges (with varying offsets) here and 
there, like if the area were allocated for vmalloc(). The problem is that we 
have an allocated anonymous memory range (which the checksum is accessing) 
before the 4M hole!

80000000-80514000 rwxp 00000000 fd:00 540678     /vbin/kernel/2.6.18-linode25
80514000-80607000 rwxp 80514000 00:00 0          [heap]
80607000-92c00000 rwxs 00607000 00:16
	738427     /linodes/encode1/tmp/vm_file-AVT0fb (deleted)
<hole here>
93000000-9300b000 rwxs 006b6000 00:16
	738427     /linodes/encode1/tmp/vm_file-AVT0fb (deleted)
9300c000-93017000 rwxs 006c2000 00:16
	738427     /linodes/encode1/tmp/vm_file-AVT0fb (deleted)

I can't follow this code at the moment, so I go for now.
Bye!
-- 
Inform me of my mistakes, so I can keep imitating Homer Simpson's "Doh!".
Paolo Giarrusso, aka Blaisorblade
http://www.user-mode-linux.org/~blaisorblade
Chiacchiera con i tuoi amici in tempo reale! 
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Re: [uml-devel] Kernel mode fault at addr 0x92c00000, ip 0x80bcead

[Christopher S. Aker]

Blaisorblade wrote:
> Which is the cmd line? With how much memory where these instances started?

Kernel command line: mem=300M fake_ide fakehd con=null con0=fd:0,fd:1 
devfs=nomount root=/dev/ubda ubda=<snip> 7 ubdb=<snip> 
eth0=tuntap,encode1_0,fe:fd:46:55:81:95 token_max=400000 token_refill=512

> Ok, Jeff, I recall something but I'm not sure. I even thought kernel threads 
> mapped the whole RAM at boot in their physical range part (which is their 
> entire address space), but it does not seem so.
> 
> The host is just a 64G with 3G/1G split, however the UML is a TT+SKAS with 
> HALF_GIGS=2 (which _is_ unusual, and could be replaced with disabling TT 

Jeff had this discussion with me a few weeks ago when I was trying to 
get UML to use more than ~550M.

At that time, I tried disabling TT mode but had to revert because non-TT 
mode enabled umls wouldn't boot on some very old skas hosts of mine.  I 
suspected that you might point in the same direction he did.  That 
problem is less important since I should really just upgrade those boxes...

> entirely, which gives a free 2,75G of memory space for UML). In fact, the UML 
> binary starts at 0x8000 0000 (i.e. 2G), and there are various holes in the 
> virtual RAM mapped in kernel side - a big part of about 30M (the 
> 0x80607000-0x92c00000 range), then there is a 4M hole (the pre-vmalloc hole 
> should be 8M, but we have a 4M hole for uml_reserved after current brk()), 
> then various holes and allocated ranges (with varying offsets) here and 
> there, like if the area were allocated for vmalloc(). The problem is that we 
> have an allocated anonymous memory range (which the checksum is accessing) 
> before the 4M hole!
> 
> 80000000-80514000 rwxp 00000000 fd:00 540678     /vbin/kernel/2.6.18-linode25
> 80514000-80607000 rwxp 80514000 00:00 0          [heap]
> 80607000-92c00000 rwxs 00607000 00:16
> 	738427     /linodes/encode1/tmp/vm_file-AVT0fb (deleted)
> <hole here>
> 93000000-9300b000 rwxs 006b6000 00:16
> 	738427     /linodes/encode1/tmp/vm_file-AVT0fb (deleted)
> 9300c000-93017000 rwxs 006c2000 00:16
> 	738427     /linodes/encode1/tmp/vm_file-AVT0fb (deleted)
> 
> I can't follow this code at the moment, so I go for now.
> Bye!

-Chris

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Re: [uml-devel] Kernel mode fault at addr 0x92c00000, ip 0x80bcead

[Jeff Dike]

On Sat, Oct 14, 2006 at 02:42:59AM +0200, Blaisorblade wrote:
> > > Kernel panic - not syncing: Kernel mode fault at addr 0x92c00000, ip
> > > 0x80bcead
> Jeff, are these addresses normal? They tell that the binary is a statically 
> linked one - but what is the memory layout? Chris, can you post 
> cat /proc/<pid>/maps on a running instance of that kernel, together with host 
> and guest config (the guest's one is contained there, I know, but I don't 
> have the time to extract).

I'm not sure.  I've never trusted the numbers coming from that panic
message (which hurts debugging, I know).  I don't believe the fault
address, and the IP doesn't match anything in the symbol table, so I
don't believe that either.

> I.e. all the rest are bogus functions?

No.  Above the skb_checksum frame, there are lots of occurrences of
dst_output, which is a function pointer being passed down the stack.
What remains looks like the remnants of old stacks.

Between csum_partial and skb_checksum, there's a big frame (and I
don't know what's causing that) with what looks like old stack in it.

> There are automated solutions for this - compiling with frame pointers allows
> correct backtracing with a runtime penalty but is implemented; however, we 
> could reuse (not copy, please, we cannot maintain it) the x86 DWARF unwinder 
> (instead of using frame pointer and to slow down fast paths, additional 
> out-of-line debug info are used when the stack trace is output) - but we 
> should implement this latter one. Jeff, can you take a look at it?

Yup, that sounds like a good idea.

				Jeff

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Re: [uml-devel] Kernel mode fault at addr 0x92c00000, ip 0x80bcead

[Blaisorblade]

On Monday 16 October 2006 16:44, Jeff Dike wrote:
> On Sat, Oct 14, 2006 at 02:42:59AM +0200, Blaisorblade wrote:
> > > > Kernel panic - not syncing: Kernel mode fault at addr 0x92c00000, ip
> > > > 0x80bcead
> >
> > Jeff, are these addresses normal? They tell that the binary is a
> > statically linked one - but what is the memory layout? Chris, can you
> > post
> > cat /proc/<pid>/maps on a running instance of that kernel, together with
> > host and guest config (the guest's one is contained there, I know, but I
> > don't have the time to extract).
>
> I'm not sure.  I've never trusted the numbers coming from that panic
> message (which hurts debugging, I know).  I don't believe the fault
> address, and the IP doesn't match anything in the symbol table, so I
> don't believe that either.
Ok, this is an issue, too.
> Yup, that sounds like a good idea.
>
> 				Jeff
Btw fixing even the above issue (if possible) would be another good idea - any 
major difficulty on that?
-- 
Inform me of my mistakes, so I can keep imitating Homer Simpson's "Doh!".
Paolo Giarrusso, aka Blaisorblade
http://www.user-mode-linux.org/~blaisorblade
Chiacchiera con i tuoi amici in tempo reale! 
 http://it.yahoo.com/mail_it/foot/*http://it.messenger.yahoo.com 


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Re: [uml-devel] Kernel mode fault at addr 0x92c00000, ip 0x80bcead

[Jeff Dike]

On Sat, Oct 21, 2006 at 03:05:50AM +0200, Blaisorblade wrote:
> Btw fixing even the above issue (if possible) would be another good idea - 
> any major difficulty on that?

Not sure, I've always debugging these problems without relying on the
panic message.

Fixing it is obviously the right thing to do, though.

				Jeff

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