Re: recent -git: BUG in free_thread_xstate

["Vegard Nossum" <vegard.nossum@gmail.com>]

On Thu, Jul 24, 2008 at 1:53 AM, Matt Mackall <mpm@selenic.com> wrote:
>
> On Thu, 2008-07-24 at 01:20 +0200, Vegard Nossum wrote:
>> >> +extern void warn_on_slowpath(const char *file, int line);
>
> Mmm, fun.
>
>> >>  [<c013496f>] warn_on_slowpath+0x4f/0x70
>> >>  [<c0198041>] ? check_bytes_and_report+0x21/0xc0
>> >>  [<c04a8544>] ? __kfree_skb+0x34/0x80
>> >>  [<c0198041>] ? check_bytes_and_report+0x21/0xc0
>> >>  [<c01983ef>] ? check_object+0xdf/0x1f0
>> >>  [<c0198041>] ? check_bytes_and_report+0x21/0xc0
>> >>  [<c04a8544>] ? __kfree_skb+0x34/0x80
>> >>  [<c01983ef>] ? check_object+0xdf/0x1f0
>> >>  [<c04bbafc>] ? find_skb+0x3c/0x80
>> >>  [<c04a9f7e>] skb_copy_and_csum_dev+0xee/0x100
>> >>  [<c03539d7>] rtl8139_start_xmit+0x57/0x130
>> >>  [<c019a84b>] ? __kmalloc_track_caller+0x8b/0x120
>> >>  [<c04bba6e>] netpoll_send_skb+0x14e/0x1a0
>> >>  [<c04bbf54>] netpoll_send_udp+0x1e4/0x210
>
> Trying to warn_on from inside a network driver from inside netpoll may
> cause trouble.

Yeah.. but apparently it was fine? I'll try to disable netconsole and
see if I can still get the crash.

BTW, I posted this earlier (but without all the Ccs, and without my
debugging patch):

=============================================================================
BUG task_struct: Poison overwritten
-----------------------------------------------------------------------------
INFO: 0xf3d00000-0xf3d0006b. First byte 0x1 instead of 0x6b
INFO: Allocated in copy_process+0x68/0x1130 age=4 cpu=0 pid=4338
INFO: Freed in free_task+0x2c/0x30 age=2 cpu=0 pid=4
INFO: Slab 0xc1c25c00 objects=8 used=3 fp=0xf3d00000 flags=0x400020c3
INFO: Object 0xf3d00000 @offset=0 fp=0xf3d03fc0
 Object 0xf3d00000:  01 40 66 00 00 16 ec ee ad b9 00 1c 26 8a 70 f8
 Object 0xf3d00010:  08 00 45 00 00 54 00 00 40 00 40 01 b7 e8 c0 a8
 Object 0xf3d00020:  00 c4 c0 a8 00 ac 08 00 6e c0 df 24 55 33 75 af

And I just realized that c0 a8 00 c4 is my IP address, 192.168.0.196 :-)

So _something_ seems to be up with networking :-)

(And this is in task_struct! Wow...)


Vegard

-- 
"The animistic metaphor of the bug that maliciously sneaked in while
the programmer was not looking is intellectually dishonest as it
disguises that the error is the programmer's own creation."
	-- E. W. Dijkstra, EWD1036