Messages in this thread | ![/](/images/icornerl.gif) | | Date | Wed, 31 Jan 2024 13:29:56 -0800 | From | Greg Kroah-Hartman <> | Subject | Re: [PATCH 2/2] cnic,bnx2,bnx2x: use UIO_MEM_DMA_COHERENT |
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On Wed, Jan 31, 2024 at 11:17:32AM -0800, Chris Leech wrote: > Use the UIO_MEM_DMA_COHERENT type to properly handle mmap for > dma_alloc_coherent buffers. > > The cnic l2_ring and l2_buf mmaps have caused page refcount issues as > the dma_alloc_coherent no longer provide __GFP_COMP allocation as per > commit "dma-mapping: reject __GFP_COMP in dma_alloc_attrs". > > Fix this by having the uio device use dma_mmap_coherent. > > The bnx2 and bnx2x status block allocations are also dma_alloc_coherent, > and should use dma_mmap_coherent. They don't allocate multiple pages, > but this interface does not work correctly with an iommu enabled unless > dma_mmap_coherent is used. > > Fixes: bb73955c0b1d ("cnic: don't pass bogus GFP_ flags to dma_alloc_coherent")
This is really the commit that broke things? By adding this, are you expecting anyone to backport this change to older kernels?
thanks,
greg k-h
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