Re: [PATCH 3/5] PCI/P2PDMA: Restrict the p2pmem search to pool backed providers

[sashiko-bot@kernel.org]

> From: Leon Romanovsky <leonro@nvidia.com>
> 
> pci_p2pmem_find_many() exists to pick a provider that the caller will
> then allocate from with pci_alloc_p2pmem(), which goes straight to the
> gen_pool:
> 
> 	ret = (void *)gen_pool_alloc_owner(p2pdma->pool, size, (void **) &ref);
> 
> pci_has_p2pmem() does not ask for that pool, only for the published flag.
> The two used to be equivalent, because a provider could only exist by way
> of pci_p2pdma_add_resource(), which always creates the pool.
> 
> pcim_p2pdma_init() broke that. It registers a provider for the DMABUF
> path and never creates a pool, so pdev->p2pdma is set while
> p2pdma->pool stays NULL. Nothing publishes such a provider today, so the
> search cannot return one yet, but the flag alone no longer says what the
> caller needs.
> 
> Ask for the pool as well, so the search covers the providers its result
> is used for. A later patch documents the pdev->p2pdma lifetime and RCU
> rules.
> 
> Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
> Tested-by: Tushar Dave <tdave@nvidia.com>
> Signed-off-by: Leon Romanovsky <leonro@nvidia.com>

Sashiko has reviewed this patch and found no issues. It looks great!

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Sashiko AI review · https://sashiko.dev/#/patchset/20260830-batch-p2p-fixes-v1-0-5044e8dfbe2e@nvidia.com?part=3