4 files changed, 18 insertions, 5 deletions
diff --git a/src/pkg/runtime/asm_386.s b/src/pkg/runtime/asm_386.s
index 87dd1fa0f..40271567b 100644
--- a/src/pkg/runtime/asm_386.s
+++ b/src/pkg/runtime/asm_386.s
@@ -233,7 +233,12 @@ oncurg:
 
 	// switch to g0
 	MOVL	DX, g(CX)
-	MOVL	(g_sched+gobuf_sp)(DX), SP
+	MOVL	(g_sched+gobuf_sp)(DX), BX
+	// make it look like mstart called onM on g0, to stop traceback
+	SUBL	$4, BX
+	MOVL	$runtime·mstart(SB), DX
+	MOVL	DX, 0(BX)
+	MOVL	BX, SP
 
 	// call target function
 	ARGSIZE(0)
diff --git a/src/pkg/runtime/asm_amd64.s b/src/pkg/runtime/asm_amd64.s
index 80c2ab3c5..9103ef29e 100644
--- a/src/pkg/runtime/asm_amd64.s
+++ b/src/pkg/runtime/asm_amd64.s
@@ -226,7 +226,12 @@ oncurg:
 
 	// switch to g0
 	MOVQ	DX, g(CX)
-	MOVQ	(g_sched+gobuf_sp)(DX), SP
+	MOVQ	(g_sched+gobuf_sp)(DX), BX
+	// make it look like mstart called onM on g0, to stop traceback
+	SUBQ	$8, BX
+	MOVQ	$runtime·mstart(SB), DX
+	MOVQ	DX, 0(BX)
+	MOVQ	BX, SP
 
 	// call target function
 	ARGSIZE(0)
diff --git a/src/pkg/runtime/asm_arm.s b/src/pkg/runtime/asm_arm.s
index 54ef83621..3869696f6 100644
--- a/src/pkg/runtime/asm_arm.s
+++ b/src/pkg/runtime/asm_arm.s
@@ -219,7 +219,12 @@ oncurg:
 
 	// switch to g0
 	MOVW	R2, g
-	MOVW	(g_sched+gobuf_sp)(R2), SP
+	MOVW	(g_sched+gobuf_sp)(R2), R3
+	// make it look like mstart called onM on g0, to stop traceback
+	SUB	$4, R3, R3
+	MOVW	$runtime·mstart(SB), R4
+	MOVW	R4, 0(R3)
+	MOVW	R3, SP
 
 	// call target function
 	ARGSIZE(0)
diff --git a/src/pkg/runtime/traceback.go b/src/pkg/runtime/traceback.go
index adb03440b..ec7be28dc 100644
--- a/src/pkg/runtime/traceback.go
+++ b/src/pkg/runtime/traceback.go
@@ -40,7 +40,6 @@ var (
 	mstartPC    = funcPC(mstart)
 	newprocPC   = funcPC(newproc)
 	newstackPC  = funcPC(newstack)
-	onMPC       = funcPC(onM)
 	rt0_goPC    = funcPC(rt0_go)
 	sigpanicPC  = funcPC(sigpanic)
 
@@ -633,7 +632,6 @@ func topofstack(f *_func) bool {
 	return pc == goexitPC ||
 		pc == mstartPC ||
 		pc == mcallPC ||
-		pc == onMPC ||
 		pc == morestackPC ||
 		pc == lessstackPC ||
 		pc == rt0_goPC ||