linux-kernel - [PATCH] Revert duplicate "drm/amdgpu: disable peer-to-peer access for DCC-enabled GC12 VRAM surfaces"

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Message-Id: <20251222-fix-duplicate-amdgpu-v1-1-18e928420d15@redhat.com>
Date: Mon, 22 Dec 2025 12:42:48 -0500
From: Peter Colberg <pcolberg@...hat.com>
To: Alex Deucher <alexander.deucher@....com>, 
 Christian König <christian.koenig@....com>, 
 David Airlie <airlied@...il.com>, Simona Vetter <simona@...ll.ch>, 
 Dave Airlie <airlied@...hat.com>
Cc: amd-gfx@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org, 
 linux-kernel@...r.kernel.org, Peter Colberg <pcolberg@...hat.com>
Subject: [PATCH] Revert duplicate "drm/amdgpu: disable peer-to-peer access
 for DCC-enabled GC12 VRAM surfaces"

This reverts commit 22a36e660d014925114feb09a2680bb3c2d1e279 once,
which was merged twice due to an incorrect backmerge resolution.

Fixes: ce0478b02ed2 ("Merge tag 'v6.18-rc6' into drm-next")
Signed-off-by: Peter Colberg <pcolberg@...hat.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c | 12 ------------
 1 file changed, 12 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
index e22cfa7c6d32f286de94c6e0947c20db41894b68..c1461317eb29877446e69562a58e17a77203a79e 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
@@ -83,18 +83,6 @@ static int amdgpu_dma_buf_attach(struct dma_buf *dmabuf,
 	struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);
 	int r;
 
-	/*
-	 * Disable peer-to-peer access for DCC-enabled VRAM surfaces on GFX12+.
-	 * Such buffers cannot be safely accessed over P2P due to device-local
-	 * compression metadata. Fallback to system-memory path instead.
-	 * Device supports GFX12 (GC 12.x or newer)
-	 * BO was created with the AMDGPU_GEM_CREATE_GFX12_DCC flag
-	 *
-	 */
-	if (amdgpu_ip_version(adev, GC_HWIP, 0) >= IP_VERSION(12, 0, 0) &&
-	    bo->flags & AMDGPU_GEM_CREATE_GFX12_DCC)
-		attach->peer2peer = false;
-
 	/*
 	 * Disable peer-to-peer access for DCC-enabled VRAM surfaces on GFX12+.
 	 * Such buffers cannot be safely accessed over P2P due to device-local

---
base-commit: 9448598b22c50c8a5bb77a9103e2d49f134c9578
change-id: 20251222-fix-duplicate-amdgpu-44017b1535eb

Best regards,
-- 
Peter Colberg <pcolberg@...hat.com>