Hi,

I get the following during resume from hibernation:

[  318.951686] ata9.00: ACPI cmd ef/03:0c:00:00:00:a0 (SET FEATURES) filtered out
[  318.951688] ata9.00: ACPI cmd ef/03:46:00:00:00:a0 (SET FEATURES) filtered out
[  318.963949] ata9.00: configured for UDMA/33
[  319.103425] ata7: SATA link down (SStatus 0 SControl 300)
[  319.103452] ata6: SATA link down (SStatus 0 SControl 300)
[  319.103471] ata8: SATA link down (SStatus 0 SControl 300)
[  319.103494] ata2: SATA link down (SStatus 0 SControl 300)
[  319.103524] ata5: SATA link down (SStatus 0 SControl 300)
[  319.110095] ata4: SATA link down (SStatus 0 SControl 300)
[  319.256728] usb 3-2: reset full speed USB device using ohci_hcd and address 2
[  319.270051] ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
[  319.276717] ata3: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
[  319.281558] ata1.00: configured for UDMA/133
[  319.281891] 
[  319.281892] =======================================================
[  319.281893] [ INFO: possible circular locking dependency detected ]
[  319.281894] 2.6.37-rc7+ #16
[  319.281895] -------------------------------------------------------
[  319.281896] kworker/1:0/13333 is trying to acquire lock:
[  319.281897]  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff811271a6>] revalidate_disk+0x56/0x90
[  319.281902] 
[  319.281903] but task is already holding lock:
[  319.281903]  (&ap->scsi_scan_mutex){+.+...}, at: [<ffffffff81360420>] ata_scsi_dev_rescan+0x30/0x120
[  319.281907] 
[  319.281907] which lock already depends on the new lock.
[  319.281907] 
[  319.281908] 
[  319.281908] the existing dependency chain (in reverse order) is:
[  319.281909] 
[  319.281910] -> #3 (&ap->scsi_scan_mutex){+.+...}:
[  319.281911]        [<ffffffff8107baa7>] lock_acquire+0x57/0x70
[  319.281914]        [<ffffffff81492fae>] mutex_lock_nested+0x5e/0x380
[  319.281916]        [<ffffffff81360420>] ata_scsi_dev_rescan+0x30/0x120
[  319.281918]        [<ffffffff81060722>] process_one_work+0x1a2/0x450
[  319.281921]        [<ffffffff81061ee2>] worker_thread+0x162/0x340
[  319.281922]        [<ffffffff810668e6>] kthread+0x96/0xa0
[  319.281924]        [<ffffffff81003594>] kernel_thread_helper+0x4/0x10
[  319.281927] 
[  319.281927] -> #2 ((&ap->scsi_rescan_task)){+.+...}:
[  319.281929]        [<ffffffff8107baa7>] lock_acquire+0x57/0x70
[  319.281930]        [<ffffffff8106071c>] process_one_work+0x19c/0x450
[  319.281932]        [<ffffffff81061ee2>] worker_thread+0x162/0x340
[  319.281934]        [<ffffffff810668e6>] kthread+0x96/0xa0
[  319.281935]        [<ffffffff81003594>] kernel_thread_helper+0x4/0x10
[  319.281937] 
[  319.281937] -> #1 (events){+.+.+.}:
[  319.281939]        [<ffffffff8107baa7>] lock_acquire+0x57/0x70
[  319.281940]        [<ffffffff81060463>] start_flush_work+0xc3/0x130
[  319.281942]        [<ffffffff810604f0>] flush_work+0x20/0x50
[  319.281944]        [<ffffffff81062a2b>] schedule_on_each_cpu+0xeb/0x130
[  319.281946]        [<ffffffff810c2070>] lru_add_drain_all+0x10/0x20
[  319.281948]        [<ffffffff81120578>] invalidate_bdev+0x28/0x40
[  319.281950]        [<ffffffff8112696a>] __invalidate_device+0x4a/0x60
[  319.281952]        [<ffffffff81126a78>] flush_disk+0x18/0xa0
[  319.281953]        [<ffffffff81126be8>] check_disk_size_change+0x78/0x80
[  319.281955]        [<ffffffff811271b1>] revalidate_disk+0x61/0x90
[  319.281957]        [<ffffffff813ba499>] do_md_run+0x59/0xa0
[  319.281959]        [<ffffffff813bbb78>] md_ioctl+0x928/0x1100
[  319.281961]        [<ffffffff811b87f8>] blkdev_ioctl+0x228/0x700
[  319.281962]        [<ffffffff8112681c>] block_ioctl+0x3c/0x40
[  319.281964]        [<ffffffff81107dc7>] do_vfs_ioctl+0x97/0x580
[  319.281966]        [<ffffffff81108329>] sys_ioctl+0x79/0x90
[  319.281968]        [<ffffffff8100273b>] system_call_fastpath+0x16/0x1b
[  319.281970] 
[  319.281970] -> #0 (&bdev->bd_mutex){+.+.+.}:
[  319.281972]        [<ffffffff8107af58>] __lock_acquire+0x1698/0x1ca0
[  319.281973]        [<ffffffff8107baa7>] lock_acquire+0x57/0x70
[  319.281975]        [<ffffffff81492fae>] mutex_lock_nested+0x5e/0x380
[  319.281976]        [<ffffffff811271a6>] revalidate_disk+0x56/0x90
[  319.281978]        [<ffffffffa0055c92>] sd_rescan+0x22/0x40 [sd_mod]
[  319.281981]        [<ffffffff81346ed6>] scsi_rescan_device+0xa6/0xd0
[  319.281984]        [<ffffffff813604aa>] ata_scsi_dev_rescan+0xba/0x120
[  319.281985]        [<ffffffff81060722>] process_one_work+0x1a2/0x450
[  319.281987]        [<ffffffff81061ee2>] worker_thread+0x162/0x340
[  319.281989]        [<ffffffff810668e6>] kthread+0x96/0xa0
[  319.281990]        [<ffffffff81003594>] kernel_thread_helper+0x4/0x10
[  319.281992] 
[  319.281993] other info that might help us debug this:
[  319.281993] 
[  319.281994] 3 locks held by kworker/1:0/13333:
[  319.281995]  #0:  (events){+.+.+.}, at: [<ffffffff810606c4>] process_one_work+0x144/0x450
[  319.281998]  #1:  ((&ap->scsi_rescan_task)){+.+...}, at: [<ffffffff810606c4>] process_one_work+0x144/0x450
[  319.282000]  #2:  (&ap->scsi_scan_mutex){+.+...}, at: [<ffffffff81360420>] ata_scsi_dev_rescan+0x30/0x120
[  319.282003] 
[  319.282003] stack backtrace:
[  319.282005] Pid: 13333, comm: kworker/1:0 Not tainted 2.6.37-rc7+ #16
[  319.282006] Call Trace:
[  319.282008]  [<ffffffff81078707>] print_circular_bug+0xe7/0xf0
[  319.282010]  [<ffffffff8107af58>] __lock_acquire+0x1698/0x1ca0
[  319.282013]  [<ffffffff81044001>] ? get_parent_ip+0x11/0x50
[  319.282015]  [<ffffffff811271a6>] ? revalidate_disk+0x56/0x90
[  319.282017]  [<ffffffff8107baa7>] lock_acquire+0x57/0x70
[  319.282019]  [<ffffffff811271a6>] ? revalidate_disk+0x56/0x90
[  319.282020]  [<ffffffff810441a5>] ? add_preempt_count+0x95/0xd0
[  319.282022]  [<ffffffff81492fae>] mutex_lock_nested+0x5e/0x380
[  319.282024]  [<ffffffff811271a6>] ? revalidate_disk+0x56/0x90
[  319.282026]  [<ffffffff811c49e7>] ? kobject_put+0x27/0x60
[  319.282028]  [<ffffffff811b9784>] ? disk_get_part+0x14/0xa0
[  319.282030]  [<ffffffff81329b22>] ? put_device+0x12/0x20
[  319.282032]  [<ffffffff811271a6>] revalidate_disk+0x56/0x90
[  319.282035]  [<ffffffffa0055c92>] sd_rescan+0x22/0x40 [sd_mod]
[  319.282037]  [<ffffffff81346ed6>] scsi_rescan_device+0xa6/0xd0
[  319.282038]  [<ffffffff813604aa>] ata_scsi_dev_rescan+0xba/0x120
[  319.282040]  [<ffffffff81060722>] process_one_work+0x1a2/0x450
[  319.282042]  [<ffffffff810606c4>] ? process_one_work+0x144/0x450
[  319.282044]  [<ffffffff813603f0>] ? ata_scsi_dev_rescan+0x0/0x120
[  319.282045]  [<ffffffff81061ee2>] worker_thread+0x162/0x340
[  319.282047]  [<ffffffff81061d80>] ? worker_thread+0x0/0x340
[  319.282049]  [<ffffffff810668e6>] kthread+0x96/0xa0
[  319.282051]  [<ffffffff81003594>] kernel_thread_helper+0x4/0x10
[  319.282052]  [<ffffffff810375ab>] ? finish_task_switch+0x7b/0xe0
[  319.282055]  [<ffffffff81495d00>] ? restore_args+0x0/0x30
[  319.282056]  [<ffffffff81066850>] ? kthread+0x0/0xa0
[  319.282058]  [<ffffffff81003590>] ? kernel_thread_helper+0x0/0x10
[  319.288123] ata3.00: configured for UDMA/133
[  319.346789] firewire_core: rediscovered device fw0
[  319.683384] usb 3-3: reset low speed USB device using ohci_hcd and address 3
[  319.992978] PM: restore of devices complete after 1208.480 msecs

The kernel is more-or-less current Linus' tree.

Full dmesg is attached, please let me know if you need any more information.

Thanks,
Rafael