• Shuah Khan's avatar
    dma-debug: New interfaces to debug dma mapping errors · 6c9c6d63
    Shuah Khan authored
    Add dma-debug interface debug_dma_mapping_error() to debug
    drivers that fail to check dma mapping errors on addresses
    returned by dma_map_single() and dma_map_page() interfaces.
    This interface clears a flag set by debug_dma_map_page() to
    indicate that dma_mapping_error() has been called by the
    driver. When driver does unmap, debug_dma_unmap() checks the
    flag and if this flag is still set, prints warning message
    that includes call trace that leads up to the unmap. This
    interface can be called from dma_mapping_error() routines to
    enable dma mapping error check debugging.
    
    Tested: Intel iommu and swiotlb (iommu=soft) on x86-64 with
            CONFIG_DMA_API_DEBUG enabled and disabled.
    Signed-off-by: default avatarShuah Khan <shuah.khan@hp.com>
    Reviewed-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
    Signed-off-by: default avatarJoerg Roedel <joerg.roedel@amd.com>
    6c9c6d63
DMA-API.txt 27.3 KB