Re: 答复: [外部邮件] Re: [PATCH] iommu/dma-iommu: Fix wrong scatterlist length assignment in P2PDMA path

[Logan Gunthorpe]

On 2026-06-02 03:48, Li,Rongqing wrote:
> AI report this commit a25e7962db0d79 ("PCI/P2PDMA: Refactor the p2pdma mapping helpers") has other issue, sg->dma_address is uninitialized in case of PCI_P2PDMA_MAP_THRU_HOST_BRIDGE in kernel/dma/direct.c, a possible fix is below:
> 
> diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
> index 583c592..4391b79 100644
> --- a/kernel/dma/direct.c
> +++ b/kernel/dma/direct.c
> @@ -476,7 +476,7 @@ int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
>                          * must be mapped with CPU physical address and not PCI
>                          * bus addresses.
>                          */
> -                       break;
> +                       fallthrough;
>                 case PCI_P2PDMA_MAP_NONE:
>                         need_sync = true;
>                         sg->dma_address = dma_direct_map_phys(dev, sg_phys(sg),
> 

Yes, this looks correct as well. Not sure how we missed that.

Reviewed-by: Logan Gunthorpe <logang@xxxxxxxxxxxx>

Thanks,

Logan