From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keith Owens <kaos@sgi.com>
Date: Fri, 27 Feb 2004 13:58:20 +0000
Subject: Re: Oops in pdflush
Message-Id: <5615.1077890300@ocs3.ocs.com.au>
List-Id: <linux-ia64.vger.kernel.org>
References: <je4qtl7u44.fsf@sykes.suse.de>
In-Reply-To: <je4qtl7u44.fsf@sykes.suse.de>
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"
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To: linux-ia64@vger.kernel.org

On Fri, 27 Feb 2004 11:16:03 +0100, 
Andreas Schwab <schwab@suse.de> wrote:
>pdflush[18140]: Oops 11012296146944 [1]
>
>Pid: 18140, CPU 1, comm:              pdflush
>psr : 0000121008026018 ifs : 8000000000000590 ip  : [<a00000010046e0d1>]    Not tainted
>ip is at nf_iterate+0x111/0x240
>unwind.init_frame_info:
>  task   0xe0000000110e0000
>  rbs = [0xe0000000110e0ef0-0xe0000000110e6ac8)
>  stk = [0xe0000000110e6ac8-0xe0000000110e8000)
>  pr     0x82aa6aa6a55596a7
>  sw     0xe0000000110e6160
>  sp     0xe0000000110e6ac8

Ouch.  rbs and stack have collided, kernel stack overflow.  rbs shows
a normal start, then it loops with the same data over and over again

0xe0000000110e0ef0 3d0bf108   ....=.ñ.
0xe0000000110e0ef8 3fdad668   ....?ÚÖh
0xe0000000110e0f00 3d376460   ....}`
0xe0000000110e0f08 3c72c008   ....<rÀ.
0xe0000000110e0f10 3d376660   ....`
0xe0000000110e0f18 00000000   ........
0xe0000000110e0f20 3fd1ebf8   ....?Ñëø
0xe0000000110e0f28 8000000000000001   ........
0xe0000000110e0f30 3d376e90   ....=7n.
0xe0000000110e0f38 3d376a60   ....=7j`
0xe0000000110e0f40 3d376e80   ....=7n.
0xe0000000110e0f48 3d376ea8   ....=7n¨
0xe0000000110e0f50 00000001   ........
0xe0000000110e0f58 3d376e88   ....=7n.
0xe0000000110e0f60 3d375810   ....=7X.
0xe0000000110e0f68 3c91e590   ....<.å.
0xe0000000110e0f70 3c8d7060   ....<.p`
0xe0000000110e0f78 00000206   ........
0xe0000000110e0f80 3cb02000   ....<° .
0xe0000000110e0f88 3d0bf108   ....=.ñ.
0xe0000000110e0f90 00001491   ........
0xe0000000110e0f98 3c8d8b50   ....<..P
0xe0000000110e0fa0 00000998   ........
0xe0000000110e0fa8 80000000afb5952b   ....¯µ.+
0xe0000000110e0fb0 3ff42000   ....?ô .
0xe0000000110e0fb8 00000001   ........
0xe0000000110e0fc0 3fdacd90   ....?ÚÍ.
0xe0000000110e0fc8 a00000010082d898 num_physpages  
0xe0000000110e0fd0 a0000001000085a0 _start+0x280  
0xe0000000110e0fd8 00000998   ........
0xe0000000110e0fe0 a000000100a17200    ....¡r.
0xe0000000110e0fe8 a00000010068ce90 start_kernel+0x530  
0xe0000000110e0ff0 00000611   ........
0xe0000000110e0ff8 00000000   ........
0xe0000000110e1000 00000611   ........
0xe0000000110e1008 a000000100680990 __kstrtab_csum_partial_copy_nocheck+0xbc80  
0xe0000000110e1010 00000000   ........
0xe0000000110e1018 00000000   ........
0xe0000000110e1020 e0000000046e0000   à....n..
0xe0000000110e1028 a000000100009090 rest_init+0x30  
0xe0000000110e1030 00000186   ........
0xe0000000110e1038 a000000100a17200    ....¡r.
0xe0000000110e1040 a0000001006de230 __initcall_pdflush_init  
0xe0000000110e1048 00000000   ........
0xe0000000110e1050 a000000100818660 _GLOBAL_OFFSET_TABLE_+0x1460  
0xe0000000110e1058 a000000100818668 _GLOBAL_OFFSET_TABLE_+0x1468  
0xe0000000110e1060 a000000100818678 _GLOBAL_OFFSET_TABLE_+0x1478  
0xe0000000110e1068 a000000100818670 _GLOBAL_OFFSET_TABLE_+0x1470  
0xe0000000110e1070 a0000001006d38f0 initcall_debug  
0xe0000000110e1078 a0000001006de4f8 __con_initcall_start  
0xe0000000110e1080 a000000100015480 kernel_thread+0x100  
0xe0000000110e1088 00000389   ........
0xe0000000110e1090 a000000100a17200    ....¡r.
0xe0000000110e1098 a000000100009600 init+0x460  
0xe0000000110e10a0 0000058e   ........
0xe0000000110e10a8 00000000   ........
0xe0000000110e10b0 a0000001006a6bd0 pdflush_init+0x30  
0xe0000000110e10b8 00000183   ........
0xe0000000110e10c0 00000000   ........
0xe0000000110e10c8 a000000100682540 __kstrtab_csum_partial_copy_nocheck+0xd830  
0xe0000000110e10d0 00000000   ........
0xe0000000110e10d8 00000000   ........
0xe0000000110e10e0 e00000003c738000   à...<s..
0xe0000000110e10e8 a0000001000eb790 start_one_pdflush_thread+0x30  
0xe0000000110e10f0 00000186   ........
0xe0000000110e10f8 a000000100a17200    ....¡r.
0xe0000000110e1100 a00000010072f670 pdflush_list  
0xe0000000110e1108 e00000003c65fe18   à...<eþ.
0xe0000000110e1110 a00000010082d858 pdflush_lock  
0xe0000000110e1118 e00000003c65fe08   à...<eþ.
0xe0000000110e1120 e00000003c65fe20   à...<eþ 
0xe0000000110e1128 a00000010082b8a0 jiffies  
0xe0000000110e1130 e00000003c65fe28   à...<eþ(
0xe0000000110e1138 00004000   ......@.
0xe0000000110e1140 00000001   ........
0xe0000000110e1148 a00000010082d860 last_empty_jifs  
0xe0000000110e1150 e00000003c65fe10   à...<eþ.
0xe0000000110e1158 a00000010081cff8 _GLOBAL_OFFSET_TABLE_+0x5df8  
0xe0000000110e1160 a00000010082ba80 nr_pdflush_threads  
0xe0000000110e1168 00000400   ........
0xe0000000110e1170 a00000010081d000 _GLOBAL_OFFSET_TABLE_+0x5e00  
0xe0000000110e1178 a00000010072f678 pdflush_list+0x8  
0xe0000000110e1180 a000000100015480 kernel_thread+0x100  
0xe0000000110e1188 00000389   ........
0xe0000000110e1190 a000000100a17200    ....¡r.
0xe0000000110e1198 a0000001000ebb40 pdflush+0x380  
0xe0000000110e11a0 00000994   ........
0xe0000000110e11a8 e00000003c65fcd8   à...<eüØ
0xe0000000110e11b0 a000000100682540 __kstrtab_csum_partial_copy_nocheck+0xd830  

Repeat from __kstrtab_csum_partial_copy_nocheck+0xd830 until the stack
overflows.  That certainly explains why the backtrace is failing.  Now
the real question is why did the code loop?