On Tue, 20 May 2025 13:59:02 -0700 Tony Nguyen wrote:
> @@ -3277,16 +3277,20 @@ static u32 idpf_rx_hsplit_wa(const struct libeth_fqe *hdr,
> struct libeth_fqe *buf, u32 data_len)
> {
> u32 copy = data_len <= L1_CACHE_BYTES ? data_len : ETH_HLEN;
> + struct page *hdr_page, *buf_page;
> const void *src;
> void *dst;
>
> - if (!libeth_rx_sync_for_cpu(buf, copy))
> + if (unlikely(netmem_is_net_iov(buf->netmem)) ||
> + !libeth_rx_sync_for_cpu(buf, copy))
> return 0;
So what happens to the packet that landed in a netmem buffer in case
when HDS failed? I don't see the handling.
> - dst = page_address(hdr->page) + hdr->offset + hdr->page->pp->p.offset;
> - src = page_address(buf->page) + buf->offset + buf->page->pp->p.offset;
> - memcpy(dst, src, LARGEST_ALIGN(copy));
> + hdr_page = __netmem_to_page(hdr->netmem);
> + buf_page = __netmem_to_page(buf->netmem);
> + dst = page_address(hdr_page) + hdr->offset + hdr_page->pp->p.offset;
> + src = page_address(buf_page) + buf->offset + buf_page->pp->p.offset;
>
> + memcpy(dst, src, LARGEST_ALIGN(copy));
> buf->offset += copy;
>
> return copy;
> @@ -3302,11 +3306,12 @@ static u32 idpf_rx_hsplit_wa(const struct libeth_fqe *hdr,
> */
> struct sk_buff *idpf_rx_build_skb(const struct libeth_fqe *buf, u32 size)
> {
> - u32 hr = buf->page->pp->p.offset;
> + struct page *buf_page = __netmem_to_page(buf->netmem);
> + u32 hr = buf_page->pp->p.offset;
> struct sk_buff *skb;
> void *va;
>
> - va = page_address(buf->page) + buf->offset;
> + va = page_address(buf_page) + buf->offset;
> prefetch(va + hr);
If you don't want to have to validate the low bit during netmem -> page
conversions - you need to clearly maintain the separation between
the two in the driver. These __netmem_to_page() calls are too much of
a liability.
