Hey,

About two-three days ago I started getting this on one of the AMD
machines I run nighly bootup test (full bootup log attached):
[Note: This is baremetal]

ehci_hcd 0000:00:02.1: reset hcc_params a086 caching frame 256/512/1024 park
BUG: Bad page state in process work_for_cpu  pfn:cf800
page:ffffea0002d64000 count:-1 mapcount:0 ing:          (null) index:0x0
page flags: 0x100000000000000()
Modules linked in:
Pid: 1207, comm: work_for_cpu Not tainted 3.4.0upstream-09208-gaf56e0a #1
Call Trace:
 [<ffffffff81103eb7>] ? dump_page+0x97/0xf0
 [<ffffffff811050bd>] bad_page+0xad/0x100
 [<ffffffff811067a2>] get_page_from_freelist+0x712/0x850
 [<ffffffff812916d8>] ? __const_udelay+0x28/0x30
 [<ffffffff81107a82>] __alloc_pages_nodemask+0x162/0x900
 [<ffffffff810a2975>] ? dequeue_task_fair+0xa5/0x330
 [<ffffffff810367e2>] ? __switch_to+0x152/0x440
 [<ffffffff8107ee37>] ? lock_timer_base+0x37/0x70
 [<ffffffff8103c7ff>] dma_generic_alloc_coherent+0x10f/0x170
 [<ffffffff81062e7e>] gart_alloc_coherent+0xee/0x120
 [<ffffffff81137542>] dma_pool_alloc+0x102/0x2e0
 [<ffffffff8109f240>] ? try_to_wake_up+0x310/0x310
 [<ffffffff813f3dc7>] ehci_qh_alloc+0x47/0xf0
 [<ffffffff813f81e7>] ehci_pci_setup+0x367/0xea0
 [<ffffffff81389213>] ? device_pm_init+0x43/0x80
 [<ffffffff813d3065>] ? usb_alloc_dev+0x2d5/0x330
 [<ffffffff81002030>] ? do_one_initcall+0x30/0x170
 [<ffffffff813db6a9>] usb_add_hcd+0x1e9/0x7a0
 [<ffffffff813ea0fa>] usb_hcd_pci_probe+0x1ba/0x3a0
 [<ffffffff81088890>] ? cwq_dec_nr_in_flight+0x90/0x90
 [<ffffffff812ad3f2>] local_pci_probe+0x12/0x20
 [<ffffffff810888a3>] do_work_for_cpu+0x13/0x30
 [<ffffffff810906e6>] kthread+0x96/0xa0
 [<ffffffff815b61e4>] kernel_thread_helper+0x4/0x10
 [<ffffffff81090650>] ? kthread_freezable_should_stop+0x70/0x70
 [<ffffffff815b61e0>] ? gs_change+0x13/0x13
Disabling lock debugging due to kernel taint
BUG: Bad page state in process work_for_cpu  pfn:cf801

I haven't actually run a git bisection, but the last git commit
that does something in the gart code looks to be this one:

commit baa676fcf8d555269bd0a5a2496782beee55824d
Author: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Date:   Tue Mar 27 14:28:18 2012 +0200

    X86 & IA64: adapt for dma_map_ops changes

hence CC-ing on this e-email.
   
Was wondering if other people had seen something similar to this?