From b8cdc05173f05d212627b7aba7ec47fa334a79f2 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Wed, 9 Mar 2016 18:56:49 -0800 Subject: [PATCH] bpf: bpf_stackmap_copy depends on CONFIG_PERF_EVENTS 0-day bot reported build error: kernel/built-in.o: In function `map_lookup_elem': >> kernel/bpf/.tmp_syscall.o:(.text+0x329b3c): undefined reference to `bpf_stackmap_copy' when CONFIG_BPF_SYSCALL is set and CONFIG_PERF_EVENTS is not. Add weak definition to resolve it. This code path in map_lookup_elem() is never taken when CONFIG_PERF_EVENTS is not set. Fixes: 557c0c6e7df8 ("bpf: convert stackmap to pre-allocation") Reported-by: Fengguang Wu Signed-off-by: Alexei Starovoitov Signed-off-by: David S. Miller --- kernel/bpf/syscall.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 2978d0d08869..2a2efe1bc76c 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -244,6 +244,11 @@ static void __user *u64_to_ptr(__u64 val) return (void __user *) (unsigned long) val; } +int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) +{ + return -ENOTSUPP; +} + /* last field in 'union bpf_attr' used by this command */ #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD value -- GitLab