From: Dan Carpenter Date: Wed, 16 Mar 2022 08:41:48 +0000 (+0300) Subject: drm/amdgpu: fix off by one in amdgpu_gfx_kiq_acquire() X-Git-Tag: v4.19.238~36 X-Git-Url: https://git.fsl.cs.sunysb.edu/?a=commitdiff_plain;h=a17d93c9088c1b7d7ec42ce25573b93544e19616;p=wrapfs-4.19.y.git drm/amdgpu: fix off by one in amdgpu_gfx_kiq_acquire() [ Upstream commit 1647b54ed55d4d48c7199d439f8834626576cbe9 ] This post-op should be a pre-op so that we do not pass -1 as the bit number to test_bit(). The current code will loop downwards from 63 to -1. After changing to a pre-op, it loops from 63 to 0. Fixes: 71c37505e7ea ("drm/amdgpu/gfx: move more common KIQ code to amdgpu_gfx.c") Signed-off-by: Dan Carpenter Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin --- diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c index 239bf2a4b3c6..eeaa2e825858 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c @@ -173,7 +173,7 @@ static int amdgpu_gfx_kiq_acquire(struct amdgpu_device *adev, * adev->gfx.mec.num_pipe_per_mec * adev->gfx.mec.num_queue_per_pipe; - while (queue_bit-- >= 0) { + while (--queue_bit >= 0) { if (test_bit(queue_bit, adev->gfx.mec.queue_bitmap)) continue;