Re: [PATCH v9 0/4] iommu/arm-smmu-v3: Tegra264 invalidation workaround
From: Will Deacon
Date: Tue Jul 28 2026 - 07:20:52 EST
On Sun, 26 Jul 2026 08:19:00 +0000, Ashish Mhetre wrote:
> Nvidia Tegra264 SMMUs are affected by an erratum where a TLB entry can
> survive an invalidation that races with concurrent traffic targeting
> the same entry. The hardware-recommended software workaround is to
> issue every CFGI/TLBI command (each followed by CMD_SYNC) twice.
> The second issue must execute only after the first issue's CMD_SYNC
> has completed, giving the sequence:
>
> [...]
Applied to iommu (arm/smmu/updates), thanks!
But please check the comments from Sashiko if you get a chance:
https://sashiko.dev/#/patchset/20260726081904.1408859-1-amhetre@xxxxxxxxxx
[1/4] iommu/arm-smmu-v3: Factor out CMDQ batch force-sync conditions
https://git.kernel.org/iommu/c/097bf4a02f2d
[2/4] iommu/arm-smmu-v3: Add CFGI/TLBI-repeat workaround
https://git.kernel.org/iommu/c/95ed2da20283
[3/4] iommu/arm-smmu-v3-iommufd: Report CFGI/TLBI-repeat erratum
https://git.kernel.org/iommu/c/d501d66815ee
[4/4] iommu/arm-smmu-v3: Enable CFGI/TLBI-repeat workaround on Tegra264
https://git.kernel.org/iommu/c/06b15ddcfbc0
Cheers,
--
Will
https://fixes.arm64.dev
https://next.arm64.dev
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