On Sun, Mar 9, 2014 at 10:51 AM, Marcin Slusarz marcin.slusarz@gmail.com wrote:
[ 326.168487] ====================================================== [ 326.168491] [ INFO: possible circular locking dependency detected ] [ 326.168496] 3.13.6 #1270 Not tainted [ 326.168500] ------------------------------------------------------- [ 326.168504] ldconfig/22297 is trying to acquire lock: [ 326.168507] (&(&priv->fan->lock)->rlock){-.-...}, at: [<ffffffffa00d5363>] nouveau_fan_update+0xeb/0x252 [nouveau] [ 326.168551] but task is already holding lock: [ 326.168555] (&(&priv->sensor.alarm_program_lock)->rlock){-.-...}, at: [<ffffffffa00d6a8a>] alarm_timer_callback+0xf1/0x179 [nouveau] [ 326.168587] which lock already depends on the new lock.
[ 326.168592] the existing dependency chain (in reverse order) is: [ 326.168596] -> #1 (&(&priv->sensor.alarm_program_lock)->rlock){-.-...}: [ 326.168606] [<ffffffff900a5656>] lock_acquire+0xce/0x117 [ 326.168615] [<ffffffff905a367e>] _raw_spin_lock_irqsave+0x3f/0x51 [ 326.168623] [<ffffffffa00d6a8a>] alarm_timer_callback+0xf1/0x179 [nouveau] [ 326.168651] [<ffffffffa00da895>] nv04_timer_alarm_trigger+0x1b1/0x1cb [nouveau] [ 326.168679] [<ffffffffa00daaa0>] nv04_timer_alarm+0xb5/0xbe [nouveau] [ 326.168708] [<ffffffffa00d54ac>] nouveau_fan_update+0x234/0x252 [nouveau] [ 326.168735] [<ffffffffa00d54df>] nouveau_fan_alarm+0x15/0x17 [nouveau] [ 326.168763] [<ffffffffa00da895>] nv04_timer_alarm_trigger+0x1b1/0x1cb [nouveau] [ 326.168790] [<ffffffffa00da90a>] nv04_timer_intr+0x5b/0x13c [nouveau] [ 326.168817] [<ffffffffa00d0e9b>] nouveau_mc_intr+0x2e2/0x3b1 [nouveau] [ 326.168838] [<ffffffff900ad359>] handle_irq_event_percpu+0x5c/0x1dc [ 326.168846] [<ffffffff900ad515>] handle_irq_event+0x3c/0x5c [ 326.168852] [<ffffffff900afa5e>] handle_edge_irq+0xc4/0xeb [ 326.168860] [<ffffffff9003a828>] handle_irq+0x120/0x12d [ 326.168868] [<ffffffff9003a2f8>] do_IRQ+0x48/0xaf [ 326.168873] [<ffffffff905a41ef>] ret_from_intr+0x0/0x13 [ 326.168881] [<ffffffff90040ea2>] arch_cpu_idle+0x13/0x1d [ 326.168887] [<ffffffff900acb2e>] cpu_startup_entry+0x140/0x218 [ 326.168895] [<ffffffff9005b0a0>] start_secondary+0x1bf/0x1c4 [ 326.168902] -> #0 (&(&priv->fan->lock)->rlock){-.-...}: [ 326.168913] [<ffffffff900a49cc>] __lock_acquire+0x10be/0x182b [ 326.168920] [<ffffffff900a5656>] lock_acquire+0xce/0x117 [ 326.168924] [<ffffffff905a367e>] _raw_spin_lock_irqsave+0x3f/0x51 [ 326.168931] [<ffffffffa00d5363>] nouveau_fan_update+0xeb/0x252 [nouveau] [ 326.168958] [<ffffffffa00d5508>] nouveau_therm_fan_set+0x14/0x16 [nouveau] [ 326.168984] [<ffffffffa00d4c6b>] nouveau_therm_update+0x303/0x312 [nouveau] [ 326.169011] [<ffffffffa00d4c8d>] nouveau_therm_alarm+0x13/0x15 [nouveau] [ 326.169038] [<ffffffffa00da895>] nv04_timer_alarm_trigger+0x1b1/0x1cb [nouveau] [ 326.169059] [<ffffffffa00daaa0>] nv04_timer_alarm+0xb5/0xbe [nouveau] [ 326.169079] [<ffffffffa00d6af7>] alarm_timer_callback+0x15e/0x179 [nouveau] [ 326.169101] [<ffffffffa00da895>] nv04_timer_alarm_trigger+0x1b1/0x1cb [nouveau] [ 326.169121] [<ffffffffa00da90a>] nv04_timer_intr+0x5b/0x13c [nouveau] [ 326.169142] [<ffffffffa00d0e9b>] nouveau_mc_intr+0x2e2/0x3b1 [nouveau] [ 326.169160] [<ffffffff900ad359>] handle_irq_event_percpu+0x5c/0x1dc [ 326.169165] [<ffffffff900ad515>] handle_irq_event+0x3c/0x5c [ 326.169170] [<ffffffff900afa5e>] handle_edge_irq+0xc4/0xeb [ 326.169175] [<ffffffff9003a828>] handle_irq+0x120/0x12d [ 326.169179] [<ffffffff9003a2f8>] do_IRQ+0x48/0xaf [ 326.169183] [<ffffffff905a41ef>] ret_from_intr+0x0/0x13 [ 326.169189] other info that might help us debug this:
[ 326.169193] Possible unsafe locking scenario:
[ 326.169195] CPU0 CPU1 [ 326.169197] ---- ---- [ 326.169199] lock(&(&priv->sensor.alarm_program_lock)->rlock); [ 326.169205] lock(&(&priv->fan->lock)->rlock); [ 326.169211] lock(&(&priv->sensor.alarm_program_lock)->rlock); [ 326.169216] lock(&(&priv->fan->lock)->rlock); [ 326.169221] *** DEADLOCK ***
[ 326.169225] 1 lock held by ldconfig/22297: [ 326.169229] #0: (&(&priv->sensor.alarm_program_lock)->rlock){-.-...}, at: [<ffffffffa00d6a8a>] alarm_timer_callback+0xf1/0x179 [nouveau] [ 326.169253] stack backtrace: [ 326.169258] CPU: 7 PID: 22297 Comm: ldconfig Not tainted 3.13.6 #1270 [ 326.169260] Hardware name: System manufacturer System Product Name/P6T SE, BIOS 0603 09/02/2009 [ 326.169264] ffffffff90fb6360 ffff8801bfdc3a38 ffffffff9059e369 0000000000000006 [ 326.169273] ffffffff90fb61b0 ffff8801bfdc3a88 ffffffff905998cf 0000000000000002 [ 326.169282] ffff8800b148dbe0 0000000000000001 ffff8800b148e1e0 0000000000000001 [ 326.169342] Call Trace: [ 326.169344] <IRQ> [<ffffffff9059e369>] dump_stack+0x4e/0x71 [ 326.169352] [<ffffffff905998cf>] print_circular_bug+0x2ad/0x2be [ 326.169356] [<ffffffff900a49cc>] __lock_acquire+0x10be/0x182b [ 326.169360] [<ffffffff900a3273>] ? check_irq_usage+0x99/0xab [ 326.169365] [<ffffffff900a5656>] lock_acquire+0xce/0x117 [ 326.169384] [<ffffffffa00d5363>] ? nouveau_fan_update+0xeb/0x252 [nouveau] [ 326.169388] [<ffffffff905a367e>] _raw_spin_lock_irqsave+0x3f/0x51 [ 326.169407] [<ffffffffa00d5363>] ? nouveau_fan_update+0xeb/0x252 [nouveau] [ 326.169426] [<ffffffffa00da871>] ? nv04_timer_alarm_trigger+0x18d/0x1cb [nouveau] [ 326.169445] [<ffffffffa00d5363>] nouveau_fan_update+0xeb/0x252 [nouveau] [ 326.169465] [<ffffffffa00d5508>] nouveau_therm_fan_set+0x14/0x16 [nouveau] [ 326.169483] [<ffffffffa00d4c6b>] nouveau_therm_update+0x303/0x312 [nouveau] [ 326.169502] [<ffffffffa00d4c8d>] nouveau_therm_alarm+0x13/0x15 [nouveau] [ 326.169521] [<ffffffffa00da895>] nv04_timer_alarm_trigger+0x1b1/0x1cb [nouveau] [ 326.169541] [<ffffffffa00daaa0>] nv04_timer_alarm+0xb5/0xbe [nouveau] [ 326.169560] [<ffffffffa00d6af7>] alarm_timer_callback+0x15e/0x179 [nouveau] [ 326.169579] [<ffffffffa00da895>] nv04_timer_alarm_trigger+0x1b1/0x1cb [nouveau] [ 326.169598] [<ffffffffa00da90a>] nv04_timer_intr+0x5b/0x13c [nouveau] [ 326.169617] [<ffffffffa00d0e9b>] nouveau_mc_intr+0x2e2/0x3b1 [nouveau] [ 326.169621] [<ffffffff900ad359>] handle_irq_event_percpu+0x5c/0x1dc [ 326.169624] [<ffffffff900ad515>] handle_irq_event+0x3c/0x5c [ 326.169628] [<ffffffff900afa5e>] handle_edge_irq+0xc4/0xeb [ 326.169631] [<ffffffff9003a828>] handle_irq+0x120/0x12d [ 326.169636] [<ffffffff90073e8c>] ? irq_enter+0x13/0x64 [ 326.169640] [<ffffffff9003a2f8>] do_IRQ+0x48/0xaf [ 326.169644] [<ffffffff905a41ef>] common_interrupt+0x6f/0x6f [ 326.169646] <EOI> [<ffffffff905a428d>] ? retint_swapgs+0xe/0x13
Marcin, how reproducible is this? What hardware was this on? If it's reasonably reproducible perhaps it makes sense to file a bug in the fd.o tracker?
Martin, I think this is in code you've written (right?). Perhaps you can take a look? All that alarm/update/etc code that ends up immediately dispatching itself seems like a locking nightmare...
-ilia