From: Adrian Hunter <[email protected]> The first symbol is not necessarily in the kernel text. Instead of using the first symbol, use the _stest symbol to identify the kernel map when loading kcore.
This allows for the introduction of symbols to identify the x86_64 PTI entry trampolines. Signed-off-by: Adrian Hunter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Dave Hansen <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Joerg Roedel <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> --- tools/perf/util/symbol.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index f48dc157c2bd..4a39f4d0a174 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -1149,7 +1149,7 @@ static int dso__load_kcore(struct dso *dso, struct map *map, bool is_64_bit; int err, fd; char kcore_filename[PATH_MAX]; - struct symbol *sym; + u64 stext; if (!kmaps) return -EINVAL; @@ -1198,13 +1198,13 @@ static int dso__load_kcore(struct dso *dso, struct map *map, old_map = next; } - /* Find the kernel map using the first symbol */ - sym = dso__first_symbol(dso); - list_for_each_entry(new_map, &md.maps, node) { - if (sym && sym->start >= new_map->start && - sym->start < new_map->end) { - replacement_map = new_map; - break; + /* Find the kernel map using the '_stext' symbol */ + if (!kallsyms__get_function_start(kallsyms_filename, "_stext", &stext)) { + list_for_each_entry(new_map, &md.maps, node) { + if (stext >= new_map->start && stext < new_map->end) { + replacement_map = new_map; + break; + } } } -- 2.14.3
