On 2018-02-16 04:26 PM, Arnd Bergmann wrote:

In randconfig testing, we sometimes get this warning:

drivers/gpu/drm/radeon/radeon_object.c: In function 'radeon_bo_create': drivers/gpu/drm/radeon/radeon_object.c:242:2: error: #warning Please enable CONFIG_MTRR and CONFIG_X86_PAT for better performance thanks to write-combining [-Werror=cpp] #warning Please enable CONFIG_MTRR and CONFIG_X86_PAT for better performance \

This is rather annoying since almost all other code produces no build-time output unless we have found a real bug. We already fixed this in the amdgpu driver in commit 31bb90f1cd08 ("drm/amdgpu: shut up #warning for compile testing") by adding a CONFIG_COMPILE_TEST check last year and agreed to do the same here, but both Michel and I then forgot about it until I came across the issue again now.

For stable kernels, as this is one of very few remaining randconfig warnings in 4.14.

Cc: stable@vger.kernel.org Link: https://patchwork.kernel.org/patch/9550009/ Signed-off-by: Arnd Bergmann arnd@arndb.de

---

drivers/gpu/drm/radeon/radeon_object.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/radeon/radeon_object.c b/drivers/gpu/drm/radeon/radeon_object.c index 093594976126..54c2b4fc5ead 100644 --- a/drivers/gpu/drm/radeon/radeon_object.c +++ b/drivers/gpu/drm/radeon/radeon_object.c @@ -238,9 +238,10 @@ int radeon_bo_create(struct radeon_device *rdev, * may be slow * See https://bugs.freedesktop.org/show_bug.cgi?id=88758 */

+#ifndef CONFIG_COMPILE_TEST #warning Please enable CONFIG_MTRR and CONFIG_X86_PAT for better performance \ thanks to write-combining +#endif if (bo->flags & RADEON_GEM_GTT_WC) DRM_INFO_ONCE("Please enable CONFIG_MTRR and CONFIG_X86_PAT for "

Merged on the internal amd-staging-drm-next branch, thanks!