-----Original Message----- From: Lu Baolu baolu.lu@linux.intel.com Sent: Tuesday, July 21, 2020 6:07 PM To: Limonciello, Mario; Joerg Roedel Cc: baolu.lu@linux.intel.com; Ashok Raj; linux-kernel@vger.kernel.org; stable@vger.kernel.org; Koba Ko; iommu@lists.linux-foundation.org Subject: Re: [PATCH 1/1] iommu/vt-d: Skip TE disabling on quirky gfx dedicated iommu
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Hi Limonciello,
On 7/21/20 10:44 PM, Limonciello, Mario wrote:
-----Original Message----- From: iommuiommu-bounces@lists.linux-foundation.org On Behalf Of Lu Baolu Sent: Monday, July 20, 2020 7:17 PM To: Joerg Roedel Cc: Ashok Raj;linux-kernel@vger.kernel.org;stable@vger.kernel.org; Koba Ko;iommu@lists.linux-foundation.org Subject: [PATCH 1/1] iommu/vt-d: Skip TE disabling on quirky gfx dedicated iommu
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.
That one is for TGL.
I think you also want to add this one for ICL: Fixes:https://bugzilla.kernel.org/show_bug.cgi?id=206571
Do you mean someone have tested that this patch also fixes the problem described in 206571?
Yes, confusingly https://bugzilla.kernel.org/show_bug.cgi?id=208363#c31 actually is the XPS 9300 ICL system and issue.
I also have a private confirmation from another person that it resolves it for them on another ICL platform.
Christian, maybe you can add a tested by clause for the ICL testing.