DMAR problem


#1

Hello~!!
this is dmesg.

0.000000] WARNING: at drivers/pci/dmar.c:634 warn_invalid_dmar+0x8f/0xa0()
0.000000] Hardware name: System Product Name
0.000000] Your BIOS is broken; DMAR reported at address fed90000 returns all ones!
0.000000] BIOS vendor: American Megatrends Inc.; Ver: 1807   ; Product Version: System Version
0.000000] Modules linked in:
0.000000] Pid: 0, comm: swapper Not tainted 2.6.37 #1
0.000000] Call Trace:
0.000000]  <ffffffff8109df3f>] warn_slowpath_common+0x7f/0xc0
0.000000]  <ffffffff8109dfdf>] warn_slowpath_fmt_taint+0x3f/0x50
0.000000]  <ffffffff81072e59>] ? native_flush_tlb_single+0x9/0x10
0.000000]  <ffffffff81072e59>] ? native_flush_tlb_single+0x9/0x10
0.000000]  <ffffffff8133b56f>] warn_invalid_dmar+0x8f/0xa0
0.000000]  <ffffffff81af0398>] check_zero_address+0xee/0x126
0.000000]  <ffffffff8137d90b>] ? acpi_get_table_with_size+0x5a/0xb4
0.000000]  <ffffffff81ad6045>] ? early_amd_iommu_detect+0x0/0x8
0.000000]  <ffffffff815f0dd6>] ? _etext+0x0/0x2
0.000000]  <ffffffff81af03e9>] detect_intel_iommu+0x19/0xb0
0.000000]  <ffffffff81ac8ce1>] pci_iommu_alloc+0x47/0x78
0.000000]  <ffffffff81ad7975>] mem_init+0x19/0xec
0.000000]  <ffffffff81ac65ac>] ? trap_init+0x1e2/0x1e9
0.000000]  <ffffffff81ac0c33>] start_kernel+0x202/0x3fb
0.000000]  <ffffffff81ac0346>] x86_64_start_reservations+0x131/0x135
0.000000]  <ffffffff81ac0452>] x86_64_start_kernel+0x108/0x117
0.000000] --- end trace a7919e7f17c0a725 ]---

line 630 at drivers/pci/dmar.c

cap = dmar_readq(addr + DMAR_CAP_REG)
ecap = dmar_readq(addr + DMAR_ECAP_REG)
early_iounmap(addr, VTD_PAGE_SIZE)
if( cap == (uint64_t)-1 && ecap == (uint64_t)-1 ){
warn_invalid_dmar(drhd->address, “returns all ones” );
goto failed;
}

so,.
if cap or ecap equal -1 , then kernel show warning message.
my mainboard is P7P55D-ASUS. use P55chipset
address is 0xfed90000

anyone have a solution?

regards
maple.