Yonghong Song <yhs@xxxxxx> writes: > On 3/19/20 6:13 AM, Toke Høiland-Jørgensen wrote: >> From: Toke Høiland-Jørgensen <toke@xxxxxxxxxx> >> >> While it is currently possible for userspace to specify that an existing >> XDP program should not be replaced when attaching to an interface, there is >> no mechanism to safely replace a specific XDP program with another. >> >> This patch adds a new netlink attribute, IFLA_XDP_EXPECTED_FD, which can be >> set along with IFLA_XDP_FD. If set, the kernel will check that the program >> currently loaded on the interface matches the expected one, and fail the >> operation if it does not. This corresponds to a 'cmpxchg' memory operation. > > The patch set itself looks good to me. But previously there is a > discussion regarding a potential similar functionality through bpf_link. > I guess maintainers (Alexei and Daniel) need to weigh in as some > future vision is involved. Right, sure. See my reply to Jakub for why I went ahead with this anyway. -Toke
