Re: 2.6.18-rc1-mm1 panic on boot x86_64 NMI watchdog detected LOCKUP

[Andrew Morton <akpm@osdl.org>]

On Tue, 11 Jul 2006 11:13:00 -0700
"Keith Mannthey" <kmannth@gmail.com> wrote:

> Hello,
>   I just tried booting 2.6.18-rc1-mm1 (I was booting 2.6.17-mm6 just
> fine) and got the following error on boot.
> 
> CPU 15: synchronized TSC with CPU 0 (last diff 49 cycles, maxerr 4698 cycles)
> Brought up 16 CPUs
> testing NMI watchdog ... OK.
> time.c: Using 333.333333 MHz WALL PIT GTOD PIT/HPET timer.
> time.c: Detected 3002.570 MHz processor.
> migration_cost=9,1121,16845
> checking if image is initramfs... it is
> Freeing initrd memory: 2770k freed
> NMI Watchdog detected LOCKUP on CPU 8
> CPU 8
> Modules linked in:
> Pid: 51, comm: khelper Not tainted 2.6.18-rc1-mm1-smp #2
> RIP: 0010:[<ffffffff803dd6f5>]  [<ffffffff803dd6f5>]
> .text.lock.spinlock+0x31/0x8a
> RSP: 0000:ffff81065f91be70  EFLAGS: 00000086
> RAX: 0000000000000000 RBX: ffff810476ce3380 RCX: 0000000000000000
> RDX: ffff81046fad4108 RSI: ffff81046fad4000 RDI: ffff810476ce3384
> RBP: ffff810476ce3380 R08: 0000000000000000 R09: 000000000036f849
> R10: 0000000000000000 R11: 0000000000000002 R12: ffff81065f91bf04
> R13: ffff81065f91bef8 R14: ffff810476dcdd18 R15: ffffffff8023f7a8
> FS:  0000000000000000(0000) GS:ffff810476f79140(0000) knlGS:0000000000000000
> CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
> CR2: 0000000000000000 CR3: 0000000000201000 CR4: 00000000000006e0
> Process khelper (pid: 51, threadinfo ffff81065f91a000, task ffff81046fedd080)
> Stack:  ffffffff803dd040 ffff81047003f8c0 ffff81065f91bef8 ffff810476dcdd18
>  0000000000000246 ffff81046fad4108 ffff810476ce3380 ffff81046fad4108
>  ffffffff8025b211 0000000000000000 0000000000000000 ffff81046fedd080
> Call Trace:
>  [<ffffffff803dd040>] __down_read+0x12/0x9a
>  [<ffffffff8025b211>] taskstats_exit_alloc+0x59/0x8a
>  [<ffffffff80232e89>] do_exit+0x178/0x8f6
>  [<ffffffff8023f940>] request_module+0x0/0x150
>  [<ffffffff8020a05a>] child_rip+0x8/0x12
>  [<ffffffff8023f7a8>] __call_usermodehelper+0x0/0x47
>  [<ffffffff8023f866>] ____call_usermodehelper+0x0/0xda
>  [<ffffffff8020a052>] child_rip+0x0/0x12
> 
> 
> Code: 7e f9 e9 d3 fe ff ff f3 90 83 3b 00 7e f9 e9 da fe ff ff e8
> console shuts up ...
> 
> 
> Any ideas, have we seen this?  I can attach config and full dmesg if needed.
> 

Thanks.  Shailabh sent the below patch through yesterday.  It looks awfully
similar.

From: Shailabh Nagar <nagar@watson.ibm.com>

Shift initialization of semaphores taken on exit() path to earlier in the
bootup sequence.  Without this fix, booting on large cpu machines hangs at
down_read() called on one of the per-cpu semaphores declared in taskstats.

Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 kernel/taskstats.c |   12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff -puN kernel/taskstats.c~per-task-delay-accounting-taskstats-interface-control-exit-data-through-cpumasks-fix-2 kernel/taskstats.c
--- a/kernel/taskstats.c~per-task-delay-accounting-taskstats-interface-control-exit-data-through-cpumasks-fix-2
+++ a/kernel/taskstats.c
@@ -501,15 +501,20 @@ static struct genl_ops taskstats_ops = {
 /* Needed early in initialization */
 void __init taskstats_init_early(void)
 {
+	unsigned int i;
+
 	taskstats_cache = kmem_cache_create("taskstats_cache",
 						sizeof(struct taskstats),
 						0, SLAB_PANIC, NULL, NULL);
+	for_each_possible_cpu(i) {
+		INIT_LIST_HEAD(&(per_cpu(listener_array, i).list));
+		init_rwsem(&(per_cpu(listener_array, i).sem));
+	}
 }
 
 static int __init taskstats_init(void)
 {
 	int rc;
-	unsigned int i;
 
 	rc = genl_register_family(&family);
 	if (rc)
@@ -519,11 +524,6 @@ static int __init taskstats_init(void)
 	if (rc < 0)
 		goto err;
 
-	for_each_possible_cpu(i) {
-		INIT_LIST_HEAD(&(per_cpu(listener_array, i).list));
-		init_rwsem(&(per_cpu(listener_array, i).sem));
-	}
-
 	family_registered = 1;
 	return 0;
 err:
_