From 94a6b384f19c16be5bfc1e0fa3048b29a41059f5 Mon Sep 17 00:00:00 2001
From: Tong Zhang <ztong0001@gmail.com>
Date: Mon, 14 Feb 2022 11:58:20 -0800
Subject: drm/i915: fix build issue when using clang
Git-commit: baf682144ecacae4b98597daa636ce7b2b3143f6
Patch-mainline: v5.18-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

drm/i915 adds some extra cflags, namely -Wall, which causes instances of
-Wformat-security to appear when building with clang, even though this
warning is turned off kernel-wide in the main Makefile:

drivers/gpu/drm/i915/gt/intel_gt.c:983:2: error: format string is not a string literal (potentially insecure) [-Werror,-Wformat-security]
        GEM_TRACE("ERROR\n");
        ^~~~~~~~~~~~~~~~~~~~
./drivers/gpu/drm/i915/i915_gem.h:76:24: note: expanded from macro 'GEM_TRACE'
 #define GEM_TRACE(...) trace_printk(__VA_ARGS__)
                       ^~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/kernel.h:369:3: note: expanded from macro 'trace_printk'
                do_trace_printk(fmt, ##__VA_ARGS__);    \
                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/kernel.h:383:30: note: expanded from macro 'do_trace_printk'
                __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args);   \
                                          ^~~~~~~~~~~~~~~~
drivers/gpu/drm/i915/gt/intel_gt.c:983:2: note: treat the string as an argument to avoid this

This does not happen with GCC because it does not enable
-Wformat-security with -Wall. Disable -Wformat-security within the i915
Makefile so that these warnings do not show up with clang.

Signed-off-by: Tong Zhang <ztong0001@gmail.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220214195821.29809-1-ztong0001@gmail.com
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/i915/Makefile | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
index 332c5bcd71a4..7686f46e42a4 100644
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -13,6 +13,7 @@
 # will most likely get a sudden build breakage... Hopefully we will fix
 # new warnings before CI updates!
 subdir-ccflags-y := -Wall -Wextra
+subdir-ccflags-y += -Wno-format-security
 subdir-ccflags-y += -Wno-unused-parameter
 subdir-ccflags-y += -Wno-type-limits
 subdir-ccflags-y += -Wno-missing-field-initializers
-- 
2.38.1