Don't pass MONO_UNWIND_ACTUAL_METHOD to the stack walker in a signal …

…handler, its not signal safe. Fixes bxc mono#263.
paulecoyote · Aug 14, 2011 · c8d809d · c8d809d
1 parent 41d9165
commit c8d809d
Show file tree

Hide file tree

Showing 2 changed files with 8 additions and 1 deletion.
diff --git a/mono/mini/debugger-agent.c b/mono/mini/debugger-agent.c
@@ -2152,7 +2152,13 @@ mono_debugger_agent_thread_interrupt (void *sigctx, MonoJitInfo *ji)
 			data.last_frame_set = FALSE;
 			if (sigctx) {
 				mono_arch_sigctx_to_monoctx (sigctx, &ctx);
-				mono_walk_stack_with_ctx (get_last_frame, &ctx, MONO_UNWIND_DEFAULT, &data);
+				mono_arch_sigctx_to_monoctx (sigctx, &ctx);
+				/* 
+				 * Don't pass MONO_UNWIND_ACTUAL_METHOD, its not signal safe, and
+				 * get_last_frame () doesn't need it, the last frame cannot be a ginst
+				 * since we are not in a JITted method.
+				 */
+				mono_walk_stack_with_ctx (get_last_frame, &ctx, MONO_UNWIND_NONE, &data);
 			}
 			if (data.last_frame_set) {
 				memcpy (&tls->async_last_frame, &data.last_frame, sizeof (StackFrameInfo));

diff --git a/mono/utils/mono-stack-unwinding.h b/mono/utils/mono-stack-unwinding.h
@@ -21,6 +21,7 @@ typedef enum {
 typedef enum {
 	MONO_UNWIND_NONE = 0x0,
 	MONO_UNWIND_LOOKUP_IL_OFFSET = 0x1,
+	/* NOT signal safe */
 	MONO_UNWIND_LOOKUP_ACTUAL_METHOD = 0x2,
 	/*
 	 * Store the locations where caller-saved registers are saved on the stack in