From 2b104fc31be0607c04188fadbd4a9fa5b50f3b99 Mon Sep 17 00:00:00 2001 From: Wenjing Liu Date: Thu, 26 Mar 2026 12:00:34 -0400 Subject: [PATCH] drm/amd/display: fix math_mod() using arg1 instead of arg2 [Why] math_mod() multiplied by arg1 instead of arg2, returning a wrong result for any non-trivial modulo operation. [How] Replace arg1 with arg2 in the subtraction term to correctly implement fmod(arg1, arg2). Cc: Mario Limonciello Cc: Alex Deucher Cc: stable@vger.kernel.org Reviewed-by: Dillon Varone Signed-off-by: Wenjing Liu Signed-off-by: Aurabindo Pillai Tested-by: Dan Wheeler Signed-off-by: Alex Deucher --- .../dml2_0/dml21/src/dml2_standalone_libraries/lib_float_math.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/dc/dml2_0/dml21/src/dml2_standalone_libraries/lib_float_math.c b/drivers/gpu/drm/amd/display/dc/dml2_0/dml21/src/dml2_standalone_libraries/lib_float_math.c index e17b5ceba4471..dc5bc649f3ac9 100644 --- a/drivers/gpu/drm/amd/display/dc/dml2_0/dml21/src/dml2_standalone_libraries/lib_float_math.c +++ b/drivers/gpu/drm/amd/display/dc/dml2_0/dml21/src/dml2_standalone_libraries/lib_float_math.c @@ -23,7 +23,7 @@ double math_mod(const double arg1, const double arg2) return arg2; if (isNaN(arg2)) return arg1; - return arg1 - arg1 * ((int)(arg1 / arg2)); + return arg1 - arg2 * ((int)(arg1 / arg2)); } double math_min2(const double arg1, const double arg2) -- 2.47.3