5 files changed, 31 insertions, 12 deletions

diff --git a/report/report.go b/report/report.go
index 5a8f4a8bd..0ade02e5d 100644
--- a/report/report.go
+++ b/report/report.go
@@ -483,11 +483,14 @@ func extractDescription(output []byte, oops *oops) string {
 	return string(output[pos:end])
 }
 
-func Symbolize(vmlinux string, text []byte) ([]byte, error) {
+func Symbolize(vmlinux string, text []byte, symbols map[string][]symbolizer.Symbol) ([]byte, error) {
 	var symbolized []byte
-	symbols, err := symbolizer.ReadSymbols(vmlinux)
-	if err != nil {
-		return nil, err
+	if symbols == nil {
+		var err error
+		symbols, err = symbolizer.ReadSymbols(vmlinux)
+		if err != nil {
+			return nil, err
+		}
 	}
 	symb := symbolizer.NewSymbolizer()
 	defer symb.Close()
diff --git a/syz-manager/cover.go b/syz-manager/cover.go
index 986d7e067..66c8630a2 100644
--- a/syz-manager/cover.go
+++ b/syz-manager/cover.go
@@ -50,8 +50,11 @@ func (a uint64Array) Less(i, j int) bool { return a[i] < a[j] }
 func (a uint64Array) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
 
 var (
-	allCoverPCs   []uint64
-	allCoverReady = make(chan bool)
+	allCoverPCs     []uint64
+	allCoverReady   = make(chan bool)
+	allSymbols      map[string][]symbolizer.Symbol
+	allSymbolsReady = make(chan bool)
+	vmOffsets     = make(map[string]uint32)
 )
 
 const (
@@ -60,6 +63,8 @@ const (
 
 func initAllCover(vmlinux string) {
 	// Running objdump on vmlinux takes 20-30 seconds, so we do it asynchronously on start.
+	// Running nm on vmlinux may takes 200 microsecond and being called during symbolization of every crash,
+	// so also do it asynchronously on start and reuse the value during each crash.
 	go func() {
 		pcs, err := coveredPCs(vmlinux)
 		if err == nil {
@@ -68,7 +73,13 @@ func initAllCover(vmlinux string) {
 		} else {
 			Logf(0, "failed to run objdump on %v: %v", vmlinux, err)
 		}
+
+		allSymbols, err = symbolizer.ReadSymbols(vmlinux)
+		if err != nil {
+			Logf(0, "failed to run nm on %v: %v", vmlinux, err)
+		}
 		close(allCoverReady)
+		close(allSymbolsReady)
 	}()
 }
 
@@ -201,6 +212,9 @@ func parseFile(fn string) ([][]byte, error) {
 }
 
 func getVmOffset(vmlinux string) (uint32, error) {
+	if v, ok := vmOffsets[vmlinux]; ok {
+		return v, nil
+	}
 	out, err := exec.Command("readelf", "-SW", vmlinux).CombinedOutput()
 	if err != nil {
 		return 0, fmt.Errorf("readelf failed: %v\n%s", err, out)
@@ -230,14 +244,15 @@ func getVmOffset(vmlinux string) (uint32, error) {
 			}
 		}
 	}
+	vmOffsets[vmlinux] = addr
 	return addr, nil
 }
 
 // uncoveredPcsInFuncs returns uncovered PCs with __sanitizer_cov_trace_pc calls in functions containing pcs.
 func uncoveredPcsInFuncs(vmlinux string, pcs []uint64) ([]uint64, error) {
-	allSymbols, err := symbolizer.ReadSymbols(vmlinux)
-	if err != nil {
-		return nil, fmt.Errorf("failed to run nm on vmlinux: %v", err)
+	<-allSymbolsReady
+	if allSymbols == nil {
+		return nil, fmt.Errorf("failed to run nm on vmlinux")
 	}
 	var symbols symbolArray
 	for name, ss := range allSymbols {
diff --git a/syz-manager/manager.go b/syz-manager/manager.go
index 55f387473..ca3552d9f 100644
--- a/syz-manager/manager.go
+++ b/syz-manager/manager.go
@@ -528,7 +528,8 @@ func (mgr *Manager) saveCrash(crash *Crash) {
 		ioutil.WriteFile(filepath.Join(dir, fmt.Sprintf("tag%v", oldestI)), []byte(mgr.cfg.Tag), 0660)
 	}
 	if len(crash.text) > 0 {
-		symbolized, err := report.Symbolize(mgr.cfg.Vmlinux, crash.text)
+		<-allSymbolsReady
+		symbolized, err := report.Symbolize(mgr.cfg.Vmlinux, crash.text, allSymbols)
 		if err != nil {
 			Logf(0, "failed to symbolize crash: %v", err)
 		} else {
diff --git a/tools/syz-report/syz-report.go b/tools/syz-report/syz-report.go
index eff8d6b8c..8d6f9785d 100644
--- a/tools/syz-report/syz-report.go
+++ b/tools/syz-report/syz-report.go
@@ -26,7 +26,7 @@ func main() {
 		fmt.Fprintf(os.Stderr, "report file does not contain a crash\n")
 		os.Exit(1)
 	}
-	symbolized, err := report.Symbolize(os.Args[1], text)
+	symbolized, err := report.Symbolize(os.Args[1], text, nil)
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "failed to symbolize report: %v\n", err)
 	} else {
diff --git a/tools/syz-symbolize/symbolize.go b/tools/syz-symbolize/symbolize.go
index d348b7148..ac2775350 100644
--- a/tools/syz-symbolize/symbolize.go
+++ b/tools/syz-symbolize/symbolize.go
@@ -32,7 +32,7 @@ func main() {
 	if console := report.ExtractConsoleOutput(text); len(console) != 0 {
 		text = console
 	}
-	text, err = report.Symbolize(filepath.Join(*flagLinux, "vmlinux"), text)
+	text, err = report.Symbolize(filepath.Join(*flagLinux, "vmlinux"), text, nil)
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "failed to symbolize: %v\n", err)
 		os.Exit(1)