Description of problem:
Lots of DMAR message from asus P6X58D motherboard

DRHD: handling fault status reg 2
DMAR:[DMA Read] Request device [03:00.0] fault addr 0 
DMAR:[fault reason 06] PTE Read access is not set

The device its complaining about is an nvidia card.


Version-Release number of selected component (if applicable):
2.6.33.3-85.fc13.x86_64


How reproducible:
Buy the hardware boot fc13


Steps to Reproduce:
1. Buy an ASUS P6X58D Motherboard
2. Turn on VT-d support in the bios
3. Install Fedora 13
  
Actual results:
[drm] nouveau 0000:03:00.0: Allocating FIFO number 2
[drm] nouveau 0000:03:00.0: nouveau_channel_alloc: initialised FIFO 2
DRHD: handling fault status reg 2
DMAR:[DMA Read] Request device [03:00.0] fault addr 0 
DMAR:[fault reason 06] PTE Read access is not set
DRHD: handling fault status reg 102
DMAR:[DMA Read] Request device [03:00.0] fault addr 0 
DMAR:[fault reason 06] PTE Read access is not set
DRHD: handling fault status reg 202
... etc.


Expected results:
Much less dmesg output. 

Additional info:
Eventually the automatic bug reporting tool dumps out a message...

------------[ cut here ]------------
WARNING: at drivers/pci/intel-iommu.c:3791 init_dmars+0x373/0x739()
Hardware name: System Product Name
Your BIOS is broken; DMA routed to ISOCH DMAR unit but no TLB space.
BIOS vendor: American Megatrends Inc.; Ver: 0703   ; Product Version: System
Version
Modules linked in:
Pid: 1, comm: swapper Not tainted 2.6.33.3-85.fc13.x86_64 #1
Call Trace:
[<ffffffff8104b558>] warn_slowpath_common+0x77/0x8f
[<ffffffff8104b5bd>] warn_slowpath_fmt+0x3c/0x3e
[<ffffffff81bd0aec>] init_dmars+0x373/0x739
[<ffffffff81bd113d>] intel_iommu_init+0x28b/0x376
[<ffffffff81badb69>] ? pci_iommu_init+0x0/0x31
[<ffffffff81badb73>] pci_iommu_init+0xa/0x31
[<ffffffff8100205f>] do_one_initcall+0x59/0x154
[<ffffffff81ba6762>] kernel_init+0x210/0x26a
[<ffffffff8100a924>] kernel_thread_helper+0x4/0x10
[<ffffffff81ba6552>] ? kernel_init+0x0/0x26a
[<ffffffff8100a920>] ? kernel_thread_helper+0x0/0x10

I know there's lots of "ASUS has broken BIOS's and doesn't implement VT-d correctly!" but it would be nice to know if there's a solution. It seems some issues have been resolved with these boards.

I'll mention that I posted on bug #541397. However, didn't get much of a response on the bug. However, bug #541397 suggests the issue was with the sky2 driver for the nic card. The pci address above is complaining about the nvidia card.

$ lspci -vvv -s 03:00.0
03:00.0 VGA compatible controller: nVidia Corporation G92 [GeForce GTS 250] (rev a2) (prog-if 00 [VGA controller])
	Subsystem: Device 196e:0593
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort+ >SERR- <PERR- INTx-
	Latency: 0, Cache Line Size: 256 bytes
	Interrupt: pin A routed to IRQ 24
	Region 0: Memory at fa000000 (32-bit, non-prefetchable) [size=16M]
	Region 1: Memory at d0000000 (64-bit, prefetchable) [size=256M]
	Region 3: Memory at f8000000 (64-bit, non-prefetchable) [size=32M]
	Region 5: I/O ports at bc00 [size=128]
	Expansion ROM at fbbe0000 [disabled] [size=128K]
	Capabilities: <access denied>
	Kernel driver in use: nouveau
	Kernel modules: nouveau, nvidiafb

So not sure how the messages would be related to the nic card on the board.

Any help would be appreciated.