ftrace causing panics.

ftrace causing panics.

[Dhaval Giani]

Hi Ingo,

ftrace-cmd in -w option when being run for sometime cause this.


llm11.in.ibm.com login: [ 1002.937490] BUG: unable to handle kernel paging request at 285b0010
[ 1002.947087] IP: [<c015f7b5>] find_next_entry+0x4f/0x84
[ 1002.955091] *pdpt = 000000002d589001 *pde = 0000000000000000 
[ 1002.963651] Oops: 0000 [#1] SMP 
[ 1002.967082] Modules linked in:
[ 1002.967082] 
[ 1002.967082] Pid: 16350, comm: cat Not tainted (2.6.25-rc2-sched-devel #9)
[ 1002.967082] EIP: 0060:[<c015f7b5>] EFLAGS: 00010206 CPU: 0
[ 1002.967082] EIP is at find_next_entry+0x4f/0x84
[ 1002.967082] EAX: f6db2c60 EBX: 00000001 ECX: 00000001 EDX: f6db2c60
[ 1002.967082] ESI: 285b0000 EDI: c0850e00 EBP: eed23f04 ESP: eed23eec
[ 1002.967082]  DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
[ 1002.967082] Process cat (pid: 16350, ti=eed22000 task=f0164620 task.ti=eed22000)
[ 1002.967082] Stack: 00000000 eed23f0c f61ba550 f61ba550 f61ba550 eed23f54 eed23f18 c015f806 
[ 1002.967082]        ffffffff f61ba550 f61ba550 eed23f38 c015f8ae 00007334 f6dccfc0 f61ba5e8 
[ 1002.967082]        c0582970 f61ba5e8 f61ba550 eed23f70 c01998a8 00000f96 00000000 00001000 
[ 1002.967082] Call Trace:
[ 1002.967082]  [<c015f806>] ? find_next_entry_inc+0x1c/0x80
[ 1002.967082]  [<c015f8ae>] ? s_next+0x44/0x7e
[ 1002.967082]  [<c01998a8>] ? seq_read+0x176/0x252
[ 1002.967082]  [<c0182be6>] ? vfs_read+0x90/0x108
[ 1002.967082]  [<c0182ea2>] ? sys_read+0x40/0x65
[ 1002.967082]  [<c0105a5a>] ? sysenter_past_esp+0x5f/0x99
[ 1002.967082]  =======================
[ 1002.967082] Code: e8 2d b2 0e 00 83 f8 07 89 c3 7f 3c 8b 54 87 14 83 3a 00 74 25 50 8b 4d f0 89 f8 e8 41 ff ff ff 59 85 c0 89 c2 74 13 85 f6 74 0a <8b> 46 10 2b 42 10 8 
[ 1002.967082] EIP: [<c015f7b5>] find_next_entry+0x4f/0x84 SS:ESP 0068:eed23eec
[ 1002.967200] Kernel panic - not syncing: Fatal exception

I can send you complete dmesg offlist as it has only trace data. .config
is the same as before (expect CONFIG_SMP is now on)

-- 
regards,
Dhaval

Re: ftrace causing panics.

[Steven Rostedt]

Dhaval Giani wrote:
> Hi Ingo,
> 
> ftrace-cmd in -w option when being run for sometime cause this.
> 
> 
> llm11.in.ibm.com login: [ 1002.937490] BUG: unable to handle kernel paging request at 285b0010
> [ 1002.947087] IP: [<c015f7b5>] find_next_entry+0x4f/0x84
> 

Dhaval,

First, thanks for testing!!!!

Are you running the -mm kernel or sched-devel?  This will let me know 
which version you have.  I'm working on a queue of fixes for Ingo now, 
to incorporate into sched-devel (and later pass to Andrew for -mm).  I'm 
not sure if the new fixes will help you, but we need to get in sync, so 
that we are both looking at the same version of the code.

Thanks,

-- Steve

Re: ftrace causing panics.

[Dhaval Giani]

On Wed, Feb 20, 2008 at 10:02:18AM -0500, Steven Rostedt wrote:
> Dhaval Giani wrote:
>> Hi Ingo,
>>
>> ftrace-cmd in -w option when being run for sometime cause this.
>>
>>
>> llm11.in.ibm.com login: [ 1002.937490] BUG: unable to handle kernel paging request at 285b0010
>> [ 1002.947087] IP: [<c015f7b5>] find_next_entry+0x4f/0x84
>>
>
> Dhaval,
>
> First, thanks for testing!!!!
>

If it helps solve difficult problems, its the best tool ever! :)

> Are you running the -mm kernel or sched-devel?  This will let me know which 
> version you have.  I'm working on a queue of fixes for Ingo now, to 
> incorporate into sched-devel (and later pass to Andrew for -mm).  I'm not 
> sure if the new fixes will help you, but we need to get in sync, so that we 
> are both looking at the same version of the code.
>

sched-devel as of yesterday. (I don't think anything new has gone in
today).

[sorry, not had enough time to get to the bottom of this the last few
days]

-- 
regards,
Dhaval

Re: ftrace causing panics.

[Steven Rostedt]

Dhaval Giani wrote:

> sched-devel as of yesterday. (I don't think anything new has gone in
> today).

I just sent Ingo my fixes a few minutes ago. You may want to keep an I 
out on updates to sched-devel.

> 
> [sorry, not had enough time to get to the bottom of this the last few
> days]
> 

No prob.

-- Steve

Re: ftrace causing panics.

[Ingo Molnar]

* Steven Rostedt <srostedt@redhat.com> wrote:

>> sched-devel as of yesterday. (I don't think anything new has gone in 
>> today).
>
> I just sent Ingo my fixes a few minutes ago. You may want to keep an I 
> out on updates to sched-devel.

it's now all up in sched-devel.git.

	Ingo