Today's Next failed to boot on a x86_64 box with following traces

ACPI: Core revision 20090625
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<ffffffff81328c7b>] set_cpu_sibling_map+0x24f/0x353
PGD 0
Oops: 0002 [#1] SMP
last sysfs file:
CPU 0
Modules linked in:
Pid: 1, comm: swapper Not tainted 2.6.31-rc4-autotest-next-20090730-5-default #1 BladeCenter LS21 -[79716AA]-
RIP: 0010:[<ffffffff81328c7b>]  [<ffffffff81328c7b>] set_cpu_sibling_map+0x24f/0x353
RSP: 0018:ffff88012b319e20  EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000000cbdc
RDX: 000000000000cbf0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88012b319e80 R08: 0000000000000004 R09: ffff880028092bc0
R10: 0000000000000000 R11: 0000000000000002 R12: 0000000000000000
R13: ffff8800280362c0 R14: ffff8800280362c0 R15: 00000000000142c0
FS:  0000000000000000(0000) GS:ffff880028022000(0000) knlGS:0000000000000000
CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
CR2: 0000000000000000 CR3: 0000000001001000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process swapper (pid: 1, threadinfo ffff88012b318000, task ffff88012b316000)
Stack:
 0000000000000003 000000000000cbe8 000000000000cbf8 000000000000cbf0
<0> 000000000000cbdc 00000000000142c0 0000000000000000 0000000000000003
<0> 0000000000000004 000000000000cbf8 000000000000cbe8 00000000000142c0
Call Trace:
 [<ffffffff81664c96>] native_smp_prepare_cpus+0x146/0x3b6
 [<ffffffff8165b594>] kernel_init+0x84/0x1db
 [<ffffffff8100ca1a>] child_rip+0xa/0x20
 [<ffffffff8165b510>] ? kernel_init+0x0/0x1db
 [<ffffffff8100ca10>] ? child_rip+0x0/0x20
Code: 00 00 48 89 c2 49 23 85 b0 00 00 00 49 23 96 b0 00 00 00 48 39 c2 75 2b 49 63 c4 48 8b 55 b8 48 8b 04 c5 90 fe 63 81 48 8b 04 02 <f0> 0f ab 18 48 63 c3 48 8b 04 c5 90 fe 63 81 48 8b 04 02 f0 44
RIP  [<ffffffff81328c7b>] set_cpu_sibling_map+0x24f/0x353
 RSP <ffff88012b319e20>
CR2: 0000000000000000
---[ end trace 4eaa2a86a8e2da22 ]---
Kernel panic - not syncing: Attempted to kill init!
Pid: 1, comm: swapper Tainted: G      D    2.6.31-rc4-autotest-next-20090730-5-default #1
Call Trace:
 [<ffffffff8132bc59>] panic+0x75/0x120
 [<ffffffff8104f41a>] ? exit_ptrace+0x33/0x12b
 [<ffffffff810493c0>] do_exit+0x79/0x6c8
 [<ffffffff8132f329>] oops_end+0xb3/0xbb
 [<ffffffff8102934f>] no_context+0x1ed/0x1fc
 [<ffffffff810294f0>] __bad_area_nosemaphore+0x192/0x1b8
 [<ffffffff810ac967>] ? __alloc_pages_nodemask+0x118/0x57d
 [<ffffffff81029524>] bad_area_nosemaphore+0xe/0x10
 [<ffffffff8133077f>] do_page_fault+0x187/0x2c6
 [<ffffffff8132e86f>] page_fault+0x1f/0x30
 [<ffffffff81328c7b>] ? set_cpu_sibling_map+0x24f/0x353
 [<ffffffff81664c96>] native_smp_prepare_cpus+0x146/0x3b6
 [<ffffffff8165b594>] kernel_init+0x84/0x1db
 [<ffffffff8100ca1a>] child_rip+0xa/0x20
 [<ffffffff8165b510>] ? kernel_init+0x0/0x1db
 [<ffffffff8100ca10>] ? child_rip+0x0/0x20

The failure points to the following piece of code :

if ((c->phys_proc_id == o->phys_proc_id) &&
    (c->cpu_node_id == o->cpu_node_id)) {
         cpumask_set_cpu(i, cpu_node_mask(cpu)); << ==
         cpumask_set_cpu(cpu, cpu_node_mask(i)); << ==
}


Yesterday's Next tree worked fine. Have attached the boot log.

Thanks
-Sachin

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Sachin Sant
IBM Linux Technology Center
India Systems and Technology Labs
Bangalore, India
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