mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2025-01-09 14:43:16 +00:00
0087a681fa
Kernel imposes a pretty particular restriction on ringbuf map size. It has to be a power-of-2 multiple of page size. While generally this isn't hard for user to satisfy, sometimes it's impossible to do this declaratively in BPF source code or just plain inconvenient to do at runtime. One such example might be BPF libraries that are supposed to work on different architectures, which might not agree on what the common page size is. Let libbpf find the right size for user instead, if it turns out to not satisfy kernel requirements. If user didn't set size at all, that's most probably a mistake so don't upsize such zero size to one full page, though. Also we need to be careful about not overflowing __u32 max_entries. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20220509004148.1801791-9-andrii@kernel.org