Re: [PATCH] iommu/dma: add missing support for DMA_ATTR_MMIO for dma_iova_unlink()

[Marek Szyprowski]

On 24.11.2025 19:17, Jason Gunthorpe wrote:
> On Mon, Nov 24, 2025 at 06:09:55PM +0100, Marek Szyprowski wrote:
>> Commit c288d657dd51 added support for DMA_ATTR_MMIO attribute in the
>> dma_iova_link() code path, but missed that the CPU cache is being also
>> touched in the dma_iova_unlink() path. Fix this.
>>
>> Fixes: c288d657dd51 ("iommu/dma: implement DMA_ATTR_MMIO for dma_iova_link().")
>> Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
>> ---
>>   drivers/iommu/dma-iommu.c | 5 +++--
>>   1 file changed, 3 insertions(+), 2 deletions(-)
> Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
>
> Did you find it by code inspection?

Yes, I checked how the batched CPu sync will fit there and noticed the 
unlink path, see 
https://lore.kernel.org/all/f8a0b873-b93c-4a91-b47d-2d11bfcf36b4@xxxxxxxxxxx/

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland