Saeed Mahameed
65851c6b6d
[ Upstream commit432e629e56] When a new rx packet arrives, the rx path will decide whether to reuse the remainder of the page or not according to one of the below conditions: 1. frag_info->frag_stride == PAGE_SIZE / 2 2. frags->page_offset + frag_info->frag_size > PAGE_SIZE; The first condition is no met for when XDP is set. For XDP, page_offset is always set to priv->rx_headroom which is XDP_PACKET_HEADROOM and frag_info->frag_size is around mtu size + some padding, still the 2nd release condition will hold since XDP_PACKET_HEADROOM + 1536 < PAGE_SIZE, as a result the page will not be released and will be _wrongly_ reused for next free rx descriptor. In XDP there is an assumption to have a page per packet and reuse can break such assumption and might cause packet data corruptions. Fix this by adding an extra condition (!priv->rx_headroom) to the 2nd case to avoid page reuse when XDP is set, since rx_headroom is set to 0 for non XDP setup and set to XDP_PACKET_HEADROOM for XDP setup. No additional cache line is required for the new condition. Fixes:34db548bfb("mlx4: add page recycling in receive path") Signed-off-by: Saeed Mahameed <saeedm@mellanox.com> Signed-off-by: Tariq Toukan <tariqt@mellanox.com> Suggested-by: Martin KaFai Lau <kafai@fb.com> CC: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.