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Furthermore, clearing > the primary devid in the lookup table before calling setup_aliases() > causes rlookup_amd_iommu() to fail for aliases. This prevents clearing > the DTEs for DMA aliases. > > Fix this by replacing the manual memset with a dedicated helper that > invalidates the DTE by clearing the lower 128 bits (having the Valid bit) > first, followed by the upper 128 bits. The cleared state is then > explicitly cloned to all aliases before the lookup tables are nullified. > > Rename the function to iommu_disable_device() more accurately > reflects its intent, as we still support IRQ remapping for these devices) > > Fixes: 99fc4ac3d297 ("iommu/amd: Introduce per PCI segment alias_table") > Reported-by: sashiko-bot@kernel.org > Closes: https://lore.kernel.org/all/20260529153216.2AD1E1F00899@smtp.kernel.org/ > Suggested-by: Jason Gunthorpe > Signed-off-by: Pranjal Shrivastava Reviewed-by: Vasant Hegde -Vasant