Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf fixes from Ingo Molnar.

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Fix perf_event_for_each() to use sibling
  perf symbols: Read plt symbols from proper symtab_type binary
  tracing: Fix stacktrace of latency tracers (irqsoff and friends)
  perf tools: Add 'G' and 'H' modifiers to event parsing
  tracing: Fix regression with tracing_on
  perf tools: Drop CROSS_COMPILE from flex and bison calls
  perf report: Fix crash showing warning related to kernel maps
  tracing: Fix build breakage without CONFIG_PERF_EVENTS (again)

1 files changed, 12 insertions, 5 deletions

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 2e317438980b..cdae9b2db1cc 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -374,16 +374,23 @@ static int __cmd_report(struct perf_report *rep)
 	    (kernel_map->dso->hit &&
 	     (kernel_kmap->ref_reloc_sym == NULL ||
 	      kernel_kmap->ref_reloc_sym->addr == 0))) {
-		const struct dso *kdso = kernel_map->dso;
+		const char *desc =
+		    "As no suitable kallsyms nor vmlinux was found, kernel samples\n"
+		    "can't be resolved.";
+
+		if (kernel_map) {
+			const struct dso *kdso = kernel_map->dso;
+			if (!RB_EMPTY_ROOT(&kdso->symbols[MAP__FUNCTION])) {
+				desc = "If some relocation was applied (e.g. "
+				       "kexec) symbols may be misresolved.";
+			}
+		}
 
 		ui__warning(
 "Kernel address maps (/proc/{kallsyms,modules}) were restricted.\n\n"
 "Check /proc/sys/kernel/kptr_restrict before running 'perf record'.\n\n%s\n\n"
 "Samples in kernel modules can't be resolved as well.\n\n",
-			    RB_EMPTY_ROOT(&kdso->symbols[MAP__FUNCTION]) ?
-"As no suitable kallsyms nor vmlinux was found, kernel samples\n"
-"can't be resolved." :
-"If some relocation was applied (e.g. kexec) symbols may be misresolved.");
+		desc);
 	}
 
 	if (dump_trace) {