2 files changed, 12 insertions, 9 deletions

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 93bd2ff001f..e2c2de201ee 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -697,17 +697,18 @@ static int __cmd_record(int argc, const char **argv)
         if (err < 0)
                 err = event__synthesize_kernel_mmap(process_synthesized_event,
                                                     session, machine, "_stext");
-        if (err < 0) {
-                pr_err("Couldn't record kernel reference relocation symbol.\n");
-                return err;
-        }
+        if (err < 0)
+                pr_err("Couldn't record kernel reference relocation symbol\n"
+                       "Symbol resolution may be skewed if relocation was used (e.g. kexec).\n"
+                       "Check /proc/kallsyms permission or run as root.\n");
 
         err = event__synthesize_modules(process_synthesized_event,
                                         session, machine);
-        if (err < 0) {
-                pr_err("Couldn't record kernel reference relocation symbol.\n");
-                return err;
-        }
+        if (err < 0)
+                pr_err("Couldn't record kernel module information.\n"
+                       "Symbol resolution may be skewed if relocation was used (e.g. kexec).\n"
+                       "Check /proc/modules permission or run as root.\n");
+
         if (perf_guest)
                 perf_session__process_machines(session, event__synthesize_guest_os);
 
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index b39f499e575..0500895a45a 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -295,7 +295,9 @@ static void symbols__insert_by_name(struct rb_root *self, struct symbol *sym)
 {
         struct rb_node **p = &self->rb_node;
         struct rb_node *parent = NULL;
-        struct symbol_name_rb_node *symn = ((void *)sym) - sizeof(*parent), *s;
+        struct symbol_name_rb_node *symn, *s;
+
+        symn = container_of(sym, struct symbol_name_rb_node, sym);
 
         while (*p != NULL) {
                 parent = *p;