e814b958ad
When single-buffer xdp is loaded, the size of the buffer filled each time is 'sz = (PAGE_SIZE - headroom - tailroom)', which is the maximum packet length that the driver allows the device to pass in. Otherwise, the packet with a length greater than sz will come in, so num_buf will be greater than or equal to 2, and xdp_linearize_page() will be performed and the packet will be dropped because the total length is greater than PAGE_SIZE. So the maximum value of MTU for single-buffer xdp is 'max_sz = sz - ETH_HLEN'. Signed-off-by: Heng Qi <hengqi@linux.alibaba.com> Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
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.