This is a note to let you know that I've just added the patch titled selftests/bpf: Fix conflicts with built-in functions in bpf_iter_ksym to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: selftests-bpf-fix-conflicts-with-built-in-functions-.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 6610af5cb73acb5817c7c5e019a8aa22c195143b Author: James Hilliard <james.hilliard1@xxxxxxxxx> Date: Fri Dec 2 18:08:44 2022 -0700 selftests/bpf: Fix conflicts with built-in functions in bpf_iter_ksym [ Upstream commit ab0350c743d5c93fd88742f02b3dff12168ab435 ] Both tolower and toupper are built in c functions, we should not redefine them as this can result in a build error. Fixes the following errors: progs/bpf_iter_ksym.c:10:20: error: conflicting types for built-in function 'tolower'; expected 'int(int)' [-Werror=builtin-declaration-mismatch] 10 | static inline char tolower(char c) | ^~~~~~~ progs/bpf_iter_ksym.c:5:1: note: 'tolower' is declared in header '<ctype.h>' 4 | #include <bpf/bpf_helpers.h> +++ |+#include <ctype.h> 5 | progs/bpf_iter_ksym.c:17:20: error: conflicting types for built-in function 'toupper'; expected 'int(int)' [-Werror=builtin-declaration-mismatch] 17 | static inline char toupper(char c) | ^~~~~~~ progs/bpf_iter_ksym.c:17:20: note: 'toupper' is declared in header '<ctype.h>' See background on this sort of issue: https://stackoverflow.com/a/20582607 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=12213 (C99, 7.1.3p1) "All identifiers with external linkage in any of the following subclauses (including the future library directions) are always reserved for use as identifiers with external linkage." This is documented behavior in GCC: https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#index-std-2 Signed-off-by: James Hilliard <james.hilliard1@xxxxxxxxx> Acked-by: Andrii Nakryiko <andrii@xxxxxxxxxx> Link: https://lore.kernel.org/r/20221203010847.2191265-1-james.hilliard1@xxxxxxxxx Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_ksym.c b/tools/testing/selftests/bpf/progs/bpf_iter_ksym.c index 285c008cbf9c..9ba14c37bbcc 100644 --- a/tools/testing/selftests/bpf/progs/bpf_iter_ksym.c +++ b/tools/testing/selftests/bpf/progs/bpf_iter_ksym.c @@ -7,14 +7,14 @@ char _license[] SEC("license") = "GPL"; unsigned long last_sym_value = 0; -static inline char tolower(char c) +static inline char to_lower(char c) { if (c >= 'A' && c <= 'Z') c += ('a' - 'A'); return c; } -static inline char toupper(char c) +static inline char to_upper(char c) { if (c >= 'a' && c <= 'z') c -= ('a' - 'A'); @@ -54,7 +54,7 @@ int dump_ksym(struct bpf_iter__ksym *ctx) type = iter->type; if (iter->module_name[0]) { - type = iter->exported ? toupper(type) : tolower(type); + type = iter->exported ? to_upper(type) : to_lower(type); BPF_SEQ_PRINTF(seq, "0x%llx %c %s [ %s ] ", value, type, iter->name, iter->module_name); } else {