xtensa: fix return_address

commit ada770b1e74a77fff2d5f539bf6c42c25f4784db upstream.

return_address returns the address that is one level higher in the call
stack than requested in its argument, because level 0 corresponds to its
caller's return address. Use requested level as the number of stack
frames to skip.

This fixes the address reported by might_sleep and friends.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/xtensa/kernel/stacktrace.c b/arch/xtensa/kernel/stacktrace.c
index 0df4080..a94da7d 100644 (file)
--- a/arch/xtensa/kernel/stacktrace.c
+++ b/arch/xtensa/kernel/stacktrace.c
@@ -253,10 +253,14 @@ static int return_address_cb(struct stackframe *frame, void *data)
        return 1;
 }
 
+/*
+ * level == 0 is for the return address from the caller of this function,
+ * not from this function itself.
+ */
 unsigned long return_address(unsigned level)
 {
        struct return_addr_data r = {
-               .skip = level + 1,
+               .skip = level,
        };
        walk_stackframe(stack_pointer(NULL), return_address_cb, &r);
        return r.addr;