RAS: Validate stack pointer after error handling
RAS handling flows might involve using setjmp/longjump calls introduced
in earlier patches; therefore, it'd be good to make sure the stack has
been unwound completely after the handling.
This patch inserts ASM assertions on the RAS handling path to validate
stack.
Change-Id: I59d40d3122010c977cdeab3cce3160f3909e7e69
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
diff --git a/bl31/aarch64/ea_delegate.S b/bl31/aarch64/ea_delegate.S
index dce1f5a..d18f9e5 100644
--- a/bl31/aarch64/ea_delegate.S
+++ b/bl31/aarch64/ea_delegate.S
@@ -6,6 +6,7 @@
#include <asm_macros.S>
+#include <assert_macros.S>
#include <context.h>
#include <ea_handle.h>
@@ -143,9 +144,24 @@
mov sp, x5
mov x29, x30
+#if ENABLE_ASSERTIONS
+ /* Stash the stack pointer */
+ mov x28, sp
+#endif
bl plat_ea_handler
mov x30, x29
+#if ENABLE_ASSERTIONS
+ /*
+ * Error handling flows might involve long jumps; so upon returning from
+ * the platform error handler, validate that the we've completely
+ * unwound the stack.
+ */
+ mov x27, sp
+ cmp x28, x27
+ ASM_ASSERT(eq)
+#endif
+
/* Make SP point to context */
msr spsel, #1