• Joerg Roedel's avatar
    iommu/amd: Fix unity mapping initialization race · 522e5cb7
    Joerg Roedel authored
    There is a race condition in the AMD IOMMU init code that
    causes requested unity mappings to be blocked by the IOMMU
    for a short period of time. This results on boot failures
    and IO_PAGE_FAULTs on some machines.
    
    Fix this by making sure the unity mappings are installed
    before all other DMA is blocked.
    
    Fixes: aafd8ba0 ('iommu/amd: Implement add_device and remove_device')
    Cc: stable@vger.kernel.org # v4.2+
    Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
    522e5cb7
amd_iommu_init.c 63.1 KB