This is a note to let you know that I've just added the patch titled drm: Don't treat 0 as -1 in drm_fixp2int_ceil to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-don-t-treat-0-as-1-in-drm_fixp2int_ceil.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 1071f8b0e06a134776e9279e9bee8abebeffa70a Author: Harry Wentland <harry.wentland@xxxxxxx> Date: Wed Nov 8 11:36:20 2023 -0500 drm: Don't treat 0 as -1 in drm_fixp2int_ceil [ Upstream commit cf8837d7204481026335461629b84ac7f4538fa5 ] Unit testing this in VKMS shows that passing 0 into this function returns -1, which is highly counter- intuitive. Fix it by checking whether the input is >= 0 instead of > 0. Fixes: 64566b5e767f ("drm: Add drm_fixp_from_fraction and drm_fixp2int_ceil") Signed-off-by: Harry Wentland <harry.wentland@xxxxxxx> Reviewed-by: Simon Ser <contact@xxxxxxxxxxx> Reviewed-by: Melissa Wen <mwen@xxxxxxxxxx> Signed-off-by: Melissa Wen <melissa.srw@xxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20231108163647.106853-2-harry.wentland@xxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/include/drm/drm_fixed.h b/include/drm/drm_fixed.h index 6ea339d5de088..0c9f917a4d4be 100644 --- a/include/drm/drm_fixed.h +++ b/include/drm/drm_fixed.h @@ -95,7 +95,7 @@ static inline int drm_fixp2int_round(s64 a) static inline int drm_fixp2int_ceil(s64 a) { - if (a > 0) + if (a >= 0) return drm_fixp2int(a + DRM_FIXED_ALMOST_ONE); else return drm_fixp2int(a - DRM_FIXED_ALMOST_ONE);