Messages in this thread Patch in this message | | | Subject | Re: v2.6.25: WARNING: at kernel/lockdep.c:2437 __lock_acquire+0xc69/0xfa0() | From | Peter Zijlstra <> | Date | Mon, 21 Apr 2008 14:48:10 +0200 |
| |
On Sun, 2008-04-20 at 12:29 +0200, Vegard Nossum wrote: > Hi, > > This appears in clean v2.6.25: > > ------------[ cut here ]------------ > WARNING: at kernel/lockdep.c:2437 __lock_acquire+0xc69/0xfa0() > Pid: 1002, comm: scsi_eh_4 Not tainted 2.6.25 #379 > [<c011bb5c>] warn_on_slowpath+0x3c/0x50 > [<c013b0f9>] ? __lock_acquire+0x219/0xfa0 > [<c013b0f9>] ? __lock_acquire+0x219/0xfa0 > [<c012c2c8>] ? __kernel_text_address+0x8/0x20 > [<c0104fce>] ? dump_trace+0xce/0x120 > [<c010a56c>] ? save_stack_trace+0x1c/0x40 > [<c0138659>] ? save_trace+0x39/0xa0 > [<c013a3d1>] ? mark_lock+0x61/0x540 > [<c013bb49>] __lock_acquire+0xc69/0xfa0 > [<c012b46a>] ? __cancel_work_timer+0x5a/0x140 > [<c01082ac>] ? native_sched_clock+0x5c/0xb0 > [<c013beee>] lock_acquire+0x6e/0x90 > [<c02a8e23>] ? ata_scsi_error+0x33/0x6a0 > [<c02e4946>] _spin_lock_irqsave+0x26/0x60 > [<c02a8e23>] ? ata_scsi_error+0x33/0x6a0 > [<c02a4ee0>] ? ata_bmdma_error_handler+0x0/0x50 > [<c02a8e23>] ata_scsi_error+0x33/0x6a0 > [<c02e249a>] ? schedule+0x27a/0x410 > [<c0256dd1>] ? __scsi_iterate_devices+0x51/0x70 > [<c025c681>] ? scsi_run_host_queues+0x21/0x30 > [<c025ae5e>] scsi_error_handler+0x9e/0x4e0 > [<c02e249a>] ? schedule+0x27a/0x410 > [<c025adc0>] ? scsi_error_handler+0x0/0x4e0 > [<c012dd86>] kthread+0x36/0x60 > [<c012dd50>] ? kthread+0x0/0x60 > [<c0104c27>] kernel_thread_helper+0x7/0x10 > ======================= > ---[ end trace 5e5d737e76fd4940 ]---
Indeed, quite easy to reproduce:
diff --git a/kernel/lockdep.c b/kernel/lockdep.c index 81a4e4a..33901ef 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -2434,6 +2434,13 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass, * the hash, not class->key. */ id = class - lock_classes; + if (id >= MAX_LOCKDEP_KEYS) { + spinlock_t *slock = container_of(lock, spinlock_t, dep_map); + + printk(KERN_EMERG "magic: %x\n", slock->magic); + printk(KERN_EMERG "class: %p\n", class); + printk(KERN_EMERG "id: %u\n", id); + } if (DEBUG_LOCKS_WARN_ON(id >= MAX_LOCKDEP_KEYS)) return 0;
gives me:
ata3: PATA max PIO4 cmd 0x1e8 ctl 0x3ee irq 11 magic: c050cf60 class: c7c20e54 id: 2265185251 ------------[ cut here ]------------ WARNING: at /mnt/md0/src/linux-2.6-2/kernel/lockdep.c:2444 __lock_acquire+0x57b/0xfd0()
Looks like someone is stomping on the spinlock or just passing us garbage.
| |