Re: [PATCH slab/for-next 09/14] iommu: specify SLAB_MAY_ACCOUNT for slab-backed page table caches

[sashiko-bot@kernel.org]

> vfio, iommufd and vhost-vdpa call iommu_map() with GFP_KERNEL_ACCOUNT
> and the gfp is passed down to the drivers' page table allocations.
> Specify SLAB_MAY_ACCOUNT when the object may be charged to a memcg.
> __GFP_ACCOUNT without SLAB_MAY_ACCOUNT will not be allowed.
> 
> Paths:
>   VFIO_IOMMU_MAP_DMA -> iommu_map(GFP_KERNEL_ACCOUNT)
>     -> s390_iommu_map_pages() -> dma_walk_cpu_trans()
>     -> kmem_cache_alloc(dma_{region,page}_table_cache)
>   iommu_map(GFP_KERNEL_ACCOUNT) -> arm_v7s_map_pages()
>     -> __arm_v7s_alloc_table() -> kmem_cache_zalloc(data->l2_tables)
>   iommu_map(GFP_KERNEL_ACCOUNT) -> sun50i_iommu_map()
>     -> sun50i_dte_get_page_table() -> kmem_cache_zalloc(iommu->pt_pool)
> 
> Assisted-by: LLM
> Cc: Will Deacon <will@kernel.org>
> Cc: Robin Murphy <robin.murphy@arm.com>
> Cc: "Joerg Roedel (AMD)" <joro@8bytes.org>
> Cc: Niklas Schnelle <schnelle@linux.ibm.com>
> Cc: Matthew Rosato <mjrosato@linux.ibm.com>
> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
> Cc: Chen-Yu Tsai <wens@kernel.org>
> Cc: Jernej Skrabec <jernej.skrabec@gmail.com>
> Cc: Samuel Holland <samuel@sholland.org>
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: iommu@lists.linux.dev
> Cc: linux-s390@vger.kernel.org
> Cc: linux-sunxi@lists.linux.dev
> Signed-off-by: Harry Yoo (Meta) <harry@kernel.org>

Sashiko has reviewed this patch and found no issues.

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