iommu/vt-d: Only call dmar_acpi_dev_scope_init() if DRHD units present
authorDavid Woodhouse <David.Woodhouse@intel.com>
Fri, 28 Mar 2014 11:28:40 +0000 (11:28 +0000)
committerDavid Woodhouse <David.Woodhouse@intel.com>
Fri, 28 Mar 2014 11:28:40 +0000 (11:28 +0000)
commit63b4262478ee6384c7efb5279be54236e5d6361b
treeb76a1d8c045dd81b65d6b64463b9c4ecbbe42231
parent11f1a7768cb9179b1f1ce6b8027df7531e0704e7
iommu/vt-d: Only call dmar_acpi_dev_scope_init() if DRHD units present

As pointed out by Jörg and fixed in commit 11f1a7768 ("iommu/vt-d: Check
for NULL pointer in dmar_acpi_dev_scope_init(), this code path can
bizarrely get exercised even on AMD IOMMU systems with IRQ remapping
enabled.

In addition to the defensive check for NULL which Jörg added, let's also
just avoid calling the function at all if there aren't an Intel IOMMU
units in the system.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
drivers/iommu/dmar.c