On Tue, Sep 8, 2020 at 8:12 PM Yonghong Song <yhs@xxxxxx> wrote:
> diff --git a/tools/testing/selftests/bpf/progs/test_sysctl_loop2.c b/tools/testing/selftests/bpf/progs/test_sysctl_loop2.c
> index b2e6f9b0894d..3c292c087395 100644
> --- a/tools/testing/selftests/bpf/progs/test_sysctl_loop2.c
> +++ b/tools/testing/selftests/bpf/progs/test_sysctl_loop2.c
> @@ -18,9 +18,9 @@
> #define MAX_ULONG_STR_LEN 7
> #define MAX_VALUE_STR_LEN (TCP_MEM_LOOPS * MAX_ULONG_STR_LEN)
>
> +const char tcp_mem_name[] = "net/ipv4/tcp_mem/very_very_very_very_long_pointless_string_to_stress_byte_loop";
> static __attribute__((noinline)) int is_tcp_mem(struct bpf_sysctl *ctx)
> {
> - volatile char tcp_mem_name[] = "net/ipv4/tcp_mem/very_very_very_very_long_pointless_string_to_stress_byte_loop";
It fixes the issue with new llvm, but breaks slightly older llvm:
./test_progs -n 7/21
libbpf: load bpf program failed: Permission denied
libbpf: -- BEGIN DUMP LOG ---
libbpf:
invalid stack off=0 size=1
verification time 6975 usec
stack depth 160+64
processed 889 insns (limit 1000000) max_states_per_insn 4 total_states
14 peak_states 14 mark_read 10
libbpf: -- END LOG --
libbpf: failed to load program 'sysctl_tcp_mem'
libbpf: failed to load object 'test_sysctl_loop2.o'
test_bpf_verif_scale:FAIL:114
#7/21 test_sysctl_loop2.o:FAIL
clang --version
clang version 12.0.0 (https://github.com/llvm/llvm-project.git
6f3511a01a5227358a334803c264cfce4175ca5d)
