Re: issues with kmemleak backport

Chris Friesen
2010-01-19T21:05:50Z

I realized that I could disable CONFIG_VT, and the previous issue went
away. The system got further into the boot and started bringing up
userspace, but then gave the error below.

BUG: unable to handle kernel paging request at 83234000
IP: [<c048ad32>] scan_block+0xb2/0x100
Oops: 0000 [#1] SMP
Modules linked in: ipmi_serial_terminal_mode ipmi_serial ipmi_msghandler
ipmi_devintf

Pid: 506, comm: kmemleak Not tainted (2.6.27-pne #25)
EIP: 0060:[<c048ad32>] EFLAGS: 00010293 CPU: 1
EIP is at scan_block+0xb2/0x100
EAX: 00000001 EBX: 00000000 ECX: 00000000 EDX: 8323779c
ESI: 83234000 EDI: 83237799 EBP: f6f8bf90 ESP: f6f8bf80
DS: 0068 ES: 007b FS: 00d8 GS: 0000 SS: 0068
Process kmemleak (pid: 506, ti=f6f8a000 task=f799da40 task.ti=f6f8a000)
Stack: 00000000 00000000 f60a5454 00000000 f6f8bfc0 c048affd 00000001
c0435330
00000206 00000001 00000000 00000002 f6f8bfb8 000927c0 c048b6c0
00000000
f6f8bfd0 c048b70e c08a66b0 00000000 f6f8bfe0 c043f6cc c043f690
00000000
Call Trace:
[<c048affd>] ? kmemleak_scan+0x11d/0x3c0
[<c0435330>] ? process_timeout+0x0/0x40
[<c048b6c0>] ? kmemleak_scan_thread+0x0/0xc0
[<c048b70e>] ? kmemleak_scan_thread+0x4e/0xc0
[<c043f6cc>] ? kthread+0x3c/0x70
[<c043f690>] ? kthread+0x0/0x70
[<c0404737>] ? kernel_thread_helper+0x7/0x10
=======================
Code: 15 50 7d 92 c0 c7 43 10 4c 7d 92 c0 89 43 14 89 10 89 ca 89 d8 e8
af c1 38 00 8d b4 26 00 00 00 00 83 c6 04 39 f7 7621 8b 45 08 <8b> 1e 85
c0 0f 84 6c ff ff ff e8 ff aa 38 00 e8 fa fe ff ff 85

Looking at the function offset it appears that kmemleak_scan() is
calling scan_block() for the per-cpu section.

I'll keep digging, but any suggestions would be appreciated.

Chris