From 95b802ca9def90a2147f2d9b884123a16ed7a507 Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Tue, 18 Mar 2025 22:07:38 -0700 Subject: [PATCH] perf syscalltbl: Mask off ABI type for MIPS system calls Arnd Bergmann described that MIPS system calls don't necessarily start from 0 as an ABI prefix is applied: https://lore.kernel.org/lkml/8ed7dfb2-1e4d-4aa4-a04b-0397a89365d1@app.fastmail.com/ When decoding the "id" (aka system call number) for MIPS ignore values greater-than 1000. Signed-off-by: Ian Rogers Reviewed-by: Namhyung Kim Acked-by: Arnaldo Carvalho de Melo Link: https://lore.kernel.org/r/20250319050741.269828-12-irogers@google.com Signed-off-by: Namhyung Kim --- tools/perf/util/syscalltbl.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/tools/perf/util/syscalltbl.c b/tools/perf/util/syscalltbl.c index 4e6018e2e0b3..67a8ec10e9e4 100644 --- a/tools/perf/util/syscalltbl.c +++ b/tools/perf/util/syscalltbl.c @@ -46,6 +46,14 @@ const char *syscalltbl__name(int e_machine, int id) { const struct syscalltbl *table = find_table(e_machine); + if (e_machine == EM_MIPS && id > 1000) { + /* + * MIPS may encode the N32/64/O32 type in the high part of + * syscall number. Mask this off if present. See the values of + * __NR_N32_Linux, __NR_64_Linux, __NR_O32_Linux and __NR_Linux. + */ + id = id % 1000; + } if (table && id >= 0 && id < table->num_to_name_len) return table->num_to_name[id]; return NULL; -- 2.25.1