PCI/iommu: blacklist DMAR on Intel G31/G33 chipsets

Some BIOSes (the Intel DG33BU, for example) wrongly claim to have DMAR
when they don't. Avoid the resulting crashes when it doesn't work as
expected.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This commit is contained in:
David Woodhouse 2008-09-07 16:35:26 +01:00 committed by Jesse Barnes
parent 1941246dd9
commit cbda1ba898
1 changed files with 23 additions and 0 deletions

View File

@ -2348,11 +2348,34 @@ static void __init iommu_exit_mempool(void)
}
static int blacklist_iommu(const struct dmi_system_id *id)
{
printk(KERN_INFO "%s detected; disabling IOMMU\n",
id->ident);
dmar_disabled = 1;
return 0;
}
static struct dmi_system_id __initdata intel_iommu_dmi_table[] = {
{ /* Some DG33BU BIOS revisions advertised non-existent VT-d */
.callback = blacklist_iommu,
.ident = "Intel DG33BU",
{ DMI_MATCH(DMI_BOARD_VENDOR, "Intel Corporation"),
DMI_MATCH(DMI_BOARD_NAME, "DG33BU"),
}
},
{ }
};
void __init detect_intel_iommu(void)
{
if (swiotlb || no_iommu || iommu_detected || dmar_disabled)
return;
if (early_dmar_detect()) {
dmi_check_system(intel_iommu_dmi_table);
if (dmar_disabled)
return;
iommu_detected = 1;
}
}