On 8/17/22 11:21 PM, Daniel Borkmann wrote:
[ +Gustavo ] On 8/17/22 3:05 AM, Dave Marchevsky wrote:Commit 94dfc73e7cf4 ("treewide: uapi: Replace zero-length arrays with flexible-array members") modified bpf_lpm_trie_key struct's data member in include/uapi/linux/bpf.h, but didn't make the same change in tools dir's copy. Propagate it over and fix comment indentation as well. This is a nonfunctional change. Signed-off-by: Dave Marchevsky <davemarchevsky@xxxxxx>Gustavo, 94dfc73e7cf4 ("treewide: uapi: Replace zero-length arrays with flexible-array members") breaks BPF when copied from include/uapi/linux/bpf.h to tools/include/uapi/linux/bpf.h : CI: https://github.com/kernel-patches/bpf/runs/7885234999?check_suite_focus=true [...] CLNG-BPF [test_maps] map_ptr_kern.o CLNG-BPF [test_maps] btf__core_reloc_arrays___diff_arr_val_sz.o CLNG-BPF [test_maps] test_bpf_cookie.o progs/map_ptr_kern.c:314:26: error: field 'trie_key' with variable sized type 'struct bpf_lpm_trie_key' not at the end of a struct or class is a GNU extension [-Werror,-Wgnu-variable-sized-type-not-at-end] struct bpf_lpm_trie_key trie_key; ^ CLNG-BPF [test_maps] btf__core_reloc_type_based___diff.o 1 error generated. make: *** [Makefile:521: /tmp/runner/work/bpf/bpf/tools/testing/selftests/bpf/map_ptr_kern.o] Error 1 make: *** Waiting for unfinished jobs.... If you look at the selftest tools/testing/selftests/bpf/progs/map_ptr_kern.c +314 : /* Key of an a BPF_MAP_TYPE_LPM_TRIE entry */ struct bpf_lpm_trie_key { __u32 prefixlen; /* up to 32 for AF_INET, 128 for AF_INET6 */ __u8 data[]; /* Arbitrary size */ }; struct lpm_key { struct bpf_lpm_trie_key trie_key; __u32 data; }; Did you try to compile the tree (or selftests) with LLVM? I doubt the UX will be nice if everyone now has to add -Wno-gnu-variable-sized-type-not-at-end ..
Undone here until a different workaround can be found (affects both bpf and bpf-next): https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=3024d95a4c521c278a7504ee9e80c57c3a9750e0 Thanks, Daniel
