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From:   Oscar Carter <oscar.carter@gmx.com>
To:     Kees Cook <keescook@chromium.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Ingo Molnar <mingo@redhat.com>,
        "James E . J . Bottomley" <James.Bottomley@HansenPartnership.com>,
        Helge Deller <deller@gmx.de>
Cc:     kernel-hardening@lists.openwall.com, linux-parisc@vger.kernel.org,
        linux-kernel@vger.kernel.org, Oscar Carter <oscar.carter@gmx.com>
Subject: [PATCH] parisc/kernel/ftrace: Remove function callback casts
Date:   Sat, 27 Jun 2020 15:43:48 +0200
Message-Id: <20200627134348.30601-1-oscar.carter@gmx.com>
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In an effort to enable -Wcast-function-type in the top-level Makefile to
support Control Flow Integrity builds, remove all the function callback
casts.

To do this remove the cast to a function pointer type in the comparison
statement and add to the right and left operand a cast to unsigned long
type. This can be done since the comparison is against function address
(these operands are not function calls).

Signed-off-by: Oscar Carter <oscar.carter@gmx.com>
=2D--
 arch/parisc/kernel/ftrace.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/parisc/kernel/ftrace.c b/arch/parisc/kernel/ftrace.c
index 1df0f67ed667..86b49a5fc049 100644
=2D-- a/arch/parisc/kernel/ftrace.c
+++ b/arch/parisc/kernel/ftrace.c
@@ -64,7 +64,7 @@ void notrace __hot ftrace_function_trampoline(unsigned l=
ong parent,
 				function_trace_op, regs);

 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
-	if (ftrace_graph_return !=3D (trace_func_graph_ret_t) ftrace_stub ||
+	if ((unsigned long)ftrace_graph_return !=3D (unsigned long)ftrace_stub |=
|
 	    ftrace_graph_entry !=3D ftrace_graph_entry_stub) {
 		unsigned long *parent_rp;

=2D-
2.20.1