From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794410443; b=a9PklZOPXKfe3S6NUDs9FpnNByAK0jdn3Hrsl/43A+r3B4hIeBexzK4nTsR2CeNYbSDJ gcU8JMTjw9GGI2MlBZilnvOeqB44lYOZn+xsXwUGNFHkzv0MoVlXL/2PDbbTvrFgLtdkB T5HpZ8Y2fXnrOD8OxMPgJ7pRaadi4BT5d8PdvUVWJIzwnYs2ndQWyw3DnUwwMwaDL9VU6 f4tK1NACxECrIRskakx9xh6UMBsxwgRwB0z5FrpZ6tbO9zsSSjS/ABXy+pF0IUR/HxRRp et1iOCeElWUkUeJCYxiI3fDfYX828j55tuvUki0cIqICWubuWYEsatPcHFFl9seii3g== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794410443; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Type: Content-Transfer-Encoding; bh=a5RnG8HqesJ+zD+D1bSONlv6Lwf+6gsZd5wF2JM36x4=; b=KP/pt3uPs3CyZFGIpEWUv5kqfUyTrWnrQfUZN6Jh1OTLOIP3AUDRsjTmCZco5udKBwkn V41NZ9aH6/5EzjqrFG1hqyC8pzXYwA0C3Dt6OJ0iAN6U1cHJKVUGnaog4RXqV43UgF6Pm 1oJa7Y3QDPBghGhIeJOKy5PFoK7SWxxLkp/9iPhchaeXzoCD/9Lpj6j7hehwMUxl0kLEQ rtU3Zsk1Mi/x+lVyx47Wbu9rp2XMCuPERnu4fi+3HjvcfZBAzNunnjMn6r7FYERj1f4OV jZJ8zNKu1UpakGl7rRIRLIeanIEZuVWmnsD0wXWEWgJfcS0J4pyg0P3BbpabVyzQtqg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=OxwJT32K; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0C723606A324 for ; Wed, 11 Nov 2026 15:20:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=OxwJT32K Received: by smtp.kernel.org (Postfix) with ESMTPSA id F33AC1F00A07; Wed, 11 Nov 2026 15:20:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794410442; bh=a5RnG8HqesJ+zD+D1bSONlv6Lwf+6gsZd5wF2JM36x4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=OxwJT32KxgMuQ2jdZsIhlofERdn9YK3k79tMxgJR3V1HZGclrGg8LaeOuQTEguF2k V/8fc48G4f02xHUbk99XiZPL/Ye9mavEMM8aJi1nK7ZKr49c0+TK13B5DG6rQ9U+e/ WEOXSh1Lbo265dp9Kh5QNqz65z58UTAw/LuS2uemnDjmW4H2t9QffVPCUwld9Umc11 Npvoez4ASCAxtN9d+zWkUQIwHfq+r5K24FJMI8guxSSBFCiWk94bYWM9YI3221bYNm v7gnFnAxcQQmp6zl/L7Ld3VSukfKelpmblugWmzk8M5reeGWzUbmwysLBd3rr9/oY3 u/4IrRWmHRUfw== From: Sasha Levin To: stable@vger.kernel.org Cc: Jesse Zhang , =?UTF-8?q?Christian=20K=C3=B6nig?= , Arunpravin Paneer Selvam , Sasha Levin Subject: [PATCH 6.1.y] drm/ttm: return an error when kmapping a BO without pages Date: Wed, 11 Nov 2026 10:20:40 -0500 Message-ID: <20261111152017.2588015-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20261107054617-failed-6.1-fd485d47437b@kernel.org> References: <20261107054617-failed-6.1-fd485d47437b@kernel.org> X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Jesse Zhang [ Upstream commit fd485d47437ba1700dd47205a63b9f389a00aa36 ] ttm_tt objects for imported sg tables (ttm_bo_type_sg, set up by ttm_sg_tt_init() with TTM_TT_FLAG_EXTERNAL) only have DMA addresses and no pages array. ttm_bo_kmap() and ttm_bo_vmap() still dereference ttm->pages for them, so a driver that tries to CPU map such a BO oopses instead of getting an error: BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:ttm_bo_kmap+0x26c/0x300 [ttm] Call Trace: amdgpu_bo_kmap+0x89/0xb0 [amdgpu] amdgpu_userq_fence_read_wptr+0x116/0x170 [amdgpu] amdgpu_userq_signal_ioctl+0x3fe/0xbb0 [amdgpu] Return -EINVAL in that case, like ttm_bo_kmap_try_from_panic() already checks for a missing pages array. Fixes: 75a57669cbc8 ("drm/ttm: add ttm_sg_tt_init") Cc: stable@vger.kernel.org Suggested-by: Christian König Reviewed-by: Christian König Signed-off-by: Jesse Zhang Signed-off-by: Arunpravin Paneer Selvam Link: https://patch.msgid.link/20261009103419.4122940-1-Jesse.Zhang@amd.com [ sashal: Applied the return-value documentation changes to header comments instead of comments beside the implementations. ] Signed-off-by: Sasha Levin --- drivers/gpu/drm/ttm/ttm_bo_util.c | 7 +++++++ include/drm/ttm/ttm_bo_api.h | 4 ++-- 2 files changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c index 7f97c97b49bd2..02d07f4c29b5c 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_util.c +++ b/drivers/gpu/drm/ttm/ttm_bo_util.c @@ -335,6 +335,10 @@ static int ttm_bo_kmap_ttm(struct ttm_buffer_object *bo, if (ret) return ret; + /* Imported sg tables only come with DMA addresses, no pages to map. */ + if (!ttm->pages) + return -EINVAL; + if (num_pages == 1 && ttm->caching == ttm_cached && !(man->use_tt && (ttm->page_flags & TTM_TT_FLAG_DECRYPTED))) { /* @@ -455,6 +459,9 @@ int ttm_bo_vmap(struct ttm_buffer_object *bo, struct iosys_map *map) if (ret) return ret; + if (!ttm->pages) + return -EINVAL; + /* * We need to use vmap to get the desired page protection * or to make the buffer object look contiguous. diff --git a/include/drm/ttm/ttm_bo_api.h b/include/drm/ttm/ttm_bo_api.h index 44a538ee5e2a6..7da454640c991 100644 --- a/include/drm/ttm/ttm_bo_api.h +++ b/include/drm/ttm/ttm_bo_api.h @@ -360,7 +360,7 @@ static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map, * * Returns * -ENOMEM: Out of memory. - * -EINVAL: Invalid range. + * -EINVAL: Invalid range or the BO has no pages to map. */ int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page, unsigned long num_pages, struct ttm_bo_kmap_obj *map); @@ -386,7 +386,7 @@ void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map); * * Returns * -ENOMEM: Out of memory. - * -EINVAL: Invalid range. + * -EINVAL: Invalid range or the BO has no pages to map. */ int ttm_bo_vmap(struct ttm_buffer_object *bo, struct iosys_map *map); -- 2.53.0