]> git.ipfire.org Git - thirdparty/kernel/linux.git/commit
iommu/vt-d: Disable DMAR for Intel Q35 IGFX
authorNaval Alcalá <ari@naval.cat>
Sat, 9 May 2026 02:43:44 +0000 (10:43 +0800)
committerJoerg Roedel <joerg.roedel@amd.com>
Mon, 11 May 2026 08:19:36 +0000 (10:19 +0200)
commit2cda2e10dc8343ae01eae9e999a876b7e7d37861
treea4ef0a671a6b76aceb8be51cea9150c66852058c
parent15dd29ca620648a18a0334a3f6b26af181154a23
iommu/vt-d: Disable DMAR for Intel Q35 IGFX

Intel Q35 integrated graphics (8086:29b2) exhibits broken DMAR
behaviour similar to other G4x/GM45 devices for which DMAR is
already disabled via quirks.

When DMAR is enabled, the system may hard lock up during boot or
early device initialization, requiring a reset.

Add the missing PCI ID to the existing quirk list to disable
DMAR for this device.

Fixes: 1f76249cc3be ("iommu/vt-d: Declare Broadwell igfx dmar support snafu")
Cc: stable@vger.kernel.org
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=201185
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=216064
Signed-off-by: Naval Alcalá <ari@naval.cat>
Link: https://lore.kernel.org/r/20260410161622.13549-1-ari@naval.cat
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
drivers/iommu/intel/iommu.c