On 11 Oct 11:20, Saeed Mahameed wrote:
On 11 Oct 09:57, Niklas Schnelle wrote:Since commit 06cd555f73ca ("net/mlx5: split mlx5_cmd_init() to probe and reload routines") mlx5_cmd_init() is called in mlx5_mdev_init() which is called in probe_one() before mlx5_pci_init(). This is a problem because mlx5_pci_init() is where the DMA and coherent mask is set but mlx5_cmd_init() already does a dma_alloc_coherent(). Thus a DMA allocation is done during probe before the correct mask is set. This causes probe to fail initialization of the cmdif SW structs on s390x after that is converted to the common dma-iommu code. This is because on s390x DMA addresses below 4 GiB are reserved on current machines and unlike the old s390x specific DMA API implementation common code enforces DMA masks. Fix this by moving set_dma_caps() out of mlx5_pci_init() and into probe_one() before mlx5_mdev_init(). To match the overall naming scheme rename it to mlx5_dma_init().How about we just call mlx5_pci_init() before mlx5_mdev_init(), instead of breaking it apart ?
I just posted this RFC patch [1]: I am working in very limited conditions these days, and I don't have strong opinion on which approach to take, Leon, Niklas, please advise. The three possible solutions: 1) mlx5_pci_init() before mlx5_mdev_init(), I don't think enabling pci before initializing cmd dma would be a problem. 2) This patch. 3) Shay's patch from the link below: [1] https://patchwork.kernel.org/project/netdevbpf/patch/20231011184511.19818-1-saeed@xxxxxxxxxx/ Thanks, Saeed.
