From 820ccf8cb2b145ab9fc12651f7f80339614fa46c Mon Sep 17 00:00:00 2001
From: Nathan Chancellor <nathan@kernel.org>
Date: Fri, 31 Jan 2025 15:31:19 -0700
Subject: [PATCH] drm/amd/display: Respect user's CONFIG_FRAME_WARN more for
 dml files

Currently, there are several files in drm/amd/display that aim to have a
higher -Wframe-larger-than value to avoid instances of that warning with
a lower value from the user's configuration. However, with the way that
it is currently implemented, it does not respect the user's request via
CONFIG_FRAME_WARN for a higher stack frame limit, which can cause pain
when new instances of the warning appear and break the build due to
CONFIG_WERROR.

Adjust the logic to switch from a hard coded -Wframe-larger-than value
to only using the value as a minimum clamp and deferring to the
requested value from CONFIG_FRAME_WARN if it is higher.

Suggested-by: Harry Wentland <harry.wentland@amd.com>
Reported-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Closes: https://lore.kernel.org/2025013003-audience-opposing-7f95@gregkh/
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
---
 drivers/gpu/drm/amd/display/dc/dml/Makefile  | 14 ++++++++-----
 drivers/gpu/drm/amd/display/dc/dml2/Makefile | 22 ++++++++++++--------
 2 files changed, 22 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dml/Makefile b/drivers/gpu/drm/amd/display/dc/dml/Makefile
index 46f9c05de16e8..e1d500633dfad 100644
--- a/drivers/gpu/drm/amd/display/dc/dml/Makefile
+++ b/drivers/gpu/drm/amd/display/dc/dml/Makefile
@@ -29,11 +29,15 @@ dml_ccflags := $(CC_FLAGS_FPU)
 dml_rcflags := $(CC_FLAGS_NO_FPU)
 
 ifneq ($(CONFIG_FRAME_WARN),0)
-ifeq ($(filter y,$(CONFIG_KASAN)$(CONFIG_KCSAN)),y)
-frame_warn_flag := -Wframe-larger-than=3072
-else
-frame_warn_flag := -Wframe-larger-than=2048
-endif
+    ifeq ($(filter y,$(CONFIG_KASAN)$(CONFIG_KCSAN)),y)
+        frame_warn_limit := 3072
+    else
+        frame_warn_limit := 2048
+    endif
+
+    ifeq ($(call test-lt, $(CONFIG_FRAME_WARN), $(frame_warn_limit)),y)
+        frame_warn_flag := -Wframe-larger-than=$(frame_warn_limit)
+    endif
 endif
 
 CFLAGS_$(AMDDALPATH)/dc/dml/display_mode_lib.o := $(dml_ccflags)
diff --git a/drivers/gpu/drm/amd/display/dc/dml2/Makefile b/drivers/gpu/drm/amd/display/dc/dml2/Makefile
index 91c4f3b4bd5f4..21fd466dba26e 100644
--- a/drivers/gpu/drm/amd/display/dc/dml2/Makefile
+++ b/drivers/gpu/drm/amd/display/dc/dml2/Makefile
@@ -28,15 +28,19 @@ dml2_ccflags := $(CC_FLAGS_FPU)
 dml2_rcflags := $(CC_FLAGS_NO_FPU)
 
 ifneq ($(CONFIG_FRAME_WARN),0)
-ifeq ($(filter y,$(CONFIG_KASAN)$(CONFIG_KCSAN)),y)
-ifeq ($(CONFIG_CC_IS_CLANG)$(CONFIG_COMPILE_TEST),yy)
-frame_warn_flag := -Wframe-larger-than=4096
-else
-frame_warn_flag := -Wframe-larger-than=3072
-endif
-else
-frame_warn_flag := -Wframe-larger-than=2048
-endif
+    ifeq ($(filter y,$(CONFIG_KASAN)$(CONFIG_KCSAN)),y)
+        ifeq ($(CONFIG_CC_IS_CLANG)$(CONFIG_COMPILE_TEST),yy)
+            frame_warn_limit := 4096
+        else
+            frame_warn_limit := 3072
+        endif
+    else
+        frame_warn_limit := 2048
+    endif
+
+    ifeq ($(call test-lt, $(CONFIG_FRAME_WARN), $(frame_warn_limit)),y)
+        frame_warn_flag := -Wframe-larger-than=$(frame_warn_limit)
+    endif
 endif
 
 subdir-ccflags-y += -I$(FULL_AMD_DISPLAY_PATH)/dc/dml2
-- 
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