On Thu, Jul 23, 2020 at 09:34:37AM +0800, Lu Baolu wrote:
The VT-d spec requires (10.4.4 Global Command Register, TE field) that:
Hardware implementations supporting DMA draining must drain any in-flight DMA read/write requests queued within the Root-Complex before completing the translation enable command and reflecting the status of the command through the TES field in the Global Status register.
Unfortunately, some integrated graphic devices fail to do so after some kind of power state transition. As the result, the system might stuck in iommu_disable_translation(), waiting for the completion of TE transition.
This provides a quirk list for those devices and skips TE disabling if the qurik hits.
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=208363 Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=206571 Tested-by: Koba Ko koba.ko@canonical.com Tested-by: Jun Miao jun.miao@windriver.com Cc: Ashok Raj ashok.raj@intel.com Cc: stable@vger.kernel.org Signed-off-by: Lu Baolu baolu.lu@linux.intel.com
Applied for v5.9, thanks.