Re: [uml-devel] Re: Diagnosed and repeatable kernel mode panic in schedule() for 2.6!

[BlaisorBlade <blaisorblade_spam@yahoo.it>]

Alle 10:53, lunedì 16 febbraio 2004, Ingo Molnar ha scritto:
> * BlaisorBlade <blaisorblade_spam@yahoo.it> wrote:
> > While searching the archives, I noticed that this command:
> >
> > while /bin/true ; do /bin/true ; done
> >
> > Kernel panic: Kernel mode fault at addr 0x1f, ip 0x400d1397
> > Kernel panic: kernel BUG at kernel/exit.c:793!
>
> can you reproduce this crash even if you boot up UML via init=/bin/bash?

Now, with 2.6.3-rc2-1um, I get this message (the command was while cat 
/dev/null; do cat /dev/null; done; both with normal init and init=/bin/sh). 
Note I did not press SysRq, nor did it with mconsole; it was done by Uml 
itself (panic_exit...). However, the last time I remember that the notifier 
chain was corrupted.

The decoding of part of the "Call stack" follows (but it is normal that most 
calls are seriously screwed away? I.e. they are just values in the stack, not 
actual calls).

Kernel panic: Kernel mode fault at addr 0x94, ip 0x40059923
Kernel panic: kernel BUG at kernel/exit.c:793!

 <6>SysRq : Show Regs

EIP: 0023:[<4005b476>] CPU: 0 Not tainted ESP: 002b:bffffd44 EFLAGS: 00000286
    Not tainted
EAX: ffffffda EBX: 00000000 ECX: 00000000 EDX: 000018c0
ESI: ffffffff EDI: 00000000 EBP: 00000000 DS: 002b ES: 002b
Call Trace: [<a00c4021>] [<a001991f>] [<a00836ed>] [<a0040186>] [<a003240d>]
   [<a0032498>] [<a003492c>] [<a0026000>] [<a0034ba4>] [<a001e298>] 
[<a0017b7e>]
   [<a001e30d>] [<a001d445>] [<a001d723>] [<a001dfd4>] [<a001dfbc>] 
[<a012de98>]
   [<a001df1b>] [<a0149cdd>]

(gdb) info line *0xa00c4021
Line 327 of "drivers/char/sysrq.c" starts at address 0xa00c4021 
<handle_sysrq+49>
   and ends at 0xa00c4030 <__handle_sysrq_nolock>.
(gdb) info line *0xa001991f
Line 398 of "arch/um/kernel/um_arch.c" starts at address 0xa001991f 
<panic_exit+31> and ends at 0xa0019924 <panic_exit+36>.

(gdb) info line *0xa00836ed
Line 467 of "fs/fs-writeback.c" starts at address 0xa00836db <sync_inodes+75> 
and ends at 0xa00836f3 <sync_inodes+99>.
(gdb) info line *0xa0040186
Line 169 of "kernel/sys.c" starts at address 0xa0040180 
<notifier_call_chain+32>
   and ends at 0xa0040188 <notifier_call_chain+40>.
(gdb) info line *0xa003240d
Line 78 of "kernel/panic.c" starts at address 0xa003240d <panic+125> and ends 
at 0xa0032419 <panic+137>.
(gdb) info line *0xa0032498
Line 69 of "kernel/panic.c" starts at address 0xa0032493 <panic+259> and ends 
at 0xa00324a0 <print_tainted>.
(gdb) info line *0xa0018c19
Line 154 of "arch/um/kernel/trap_kern.c" starts at address 0xa0018c19 
<segv+121> and ends at 0xa0018c1c <segv+124>.
(gdb) info line *0xa0018d28
Line 161 of "arch/um/kernel/trap_kern.c" starts at address 0xa0018d28 
<segv+392> and ends at 0xa0018d3f <segv+415>.
(gdb) info line *0xa012e19a
Line 92 of "include/linux/slab.h" starts at address 0xa011fe16 
<unix_seq_open+22> and ends at 0xa01c3632 <af_unix_exit+18>.
(gdb) info line *0xa012e19a
Line 92 of "include/linux/slab.h" starts at address 0xa011fe16 
<unix_seq_open+22> and ends at 0xa01c3632 <af_unix_exit+18>.
(gdb) info line *0xa0016f1d
Line 69 of "arch/um/kernel/signal_user.c" starts at address 0xa0016f0e 
<change_signals+62>
   and ends at 0xa0016f24 <change_signals+84>.
(gdb) info line *0xa00190f7
Line 67 of "arch/um/kernel/trap_user.c" starts at address 0xa00190c2 
<segv_handler+306> and ends at 0xa00191b0 <usr2_handler>.
(gdb) info line *0xa001905f
Line 64 of "arch/um/kernel/trap_user.c" starts at address 0xa001905f 
<segv_handler+207>
   and ends at 0xa0019065 <segv_handler+213>.
(gdb) info line *0xa001e7f3
Line 35 of "arch/um/kernel/skas/trap_user.c" starts at address 0xa001e7f3 
<sig_handler_common_skas+115>
   and ends at 0xa001e7f8 <sig_handler_common_skas+120>.
(gdb) info line *0xa0019200
Line 103 of "arch/um/kernel/trap_user.c" starts at address 0xa00191f0 
<sig_handler+32> and ends at 0xa0019210 <alarm_handler>.
(gdb) info line *0xa012de98
Line 92 of "include/linux/slab.h" starts at address 0xa011fe16 
<unix_seq_open+22> and ends at 0xa01c3632 <af_unix_exit+18>.
(gdb) info line *0xa002ee65
Line 1680 of "kernel/sched.c" starts at address 0xa002ee65 <schedule+453> and 
ends at 0xa002ee70 <schedule+464>.
(gdb) info line *0xa012e19a
Line 92 of "include/linux/slab.h" starts at address 0xa011fe16 
<unix_seq_open+22> and ends at 0xa01c3632 <af_unix_exit+18>.
(gdb) info line *0xa00170a4
Line 127 of "arch/um/kernel/signal_user.c" starts at address 0xa0017099 
<set_signals+105>
   and ends at 0xa00170ab <set_signals+123>.
(gdb) info line *0xa002e55a
Line 301 of "kernel/sched.c" starts at address 0xa002e555 
<wake_up_forked_process+357>
   and ends at 0xa002e55d <wake_up_forked_process+365>.
(gdb) info line *0xa002e408
Line 780 of "kernel/sched.c" starts at address 0xa002e408 
<wake_up_forked_process+24>
   and ends at 0xa002e412 <wake_up_forked_process+34>.
(gdb) info line *0xa0031e4f
Line 1138 of "kernel/fork.c" starts at address 0xa0031e4f <do_fork+63> and 
ends at 0xa0031e52 <do_fork+66>.
(gdb) info line *0xa0031f47
Line 1157 of "kernel/fork.c" starts at address 0xa0031f40 <do_fork+304> and 
ends at 0xa0031f4c <do_fork+316>.
(gdb) info line *0xa0018a84
Line 90 of "arch/um/kernel/trap_kern.c" starts at address 0xa0018a7b 
<handle_page_fault+331>
   and ends at 0xa0018a8c <handle_page_fault+348>.
(gdb) info line *0xa001898c
Line 93 of "arch/um/kernel/trap_kern.c" starts at address 0xa001898c 
<handle_page_fault+92>
   and ends at 0xa0018997 <handle_page_fault+103>.

-- 
Paolo Giarrusso, aka Blaisorblade
Linux registered user n. 292729




-------------------------------------------------------
SF.Net is sponsored by: Speed Start Your Linux Apps Now.
Build and deploy apps & Web services for Linux with
a free DVD software kit from IBM. Click Now!
http://ads.osdn.com/?ad_id\x1356&alloc_id438&opÌk
_______________________________________________
User-mode-linux-devel mailing list
User-mode-linux-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel