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=1794050428; b=MT9XrDizIodzoEKQJLBGQ59XTLk+b9JoozSdR5lchsOGVhTxfWEcfQ3aKqDWqHgz7J6t 3q5wHOR8sIhmTjjOxekZIE7eKjvdnXYo8mE0aPCd8r+iULmxLvdyfy0Ncz4PRUneD1vKK 16ii7ktmC6NFkvJVSDCBCoBJieClCV7ULpjR43DUpnBVyCBOVzuo4nhzvwes50zCxi80c Uep4rWgA789u9dg3TsHzGBgAmfddG/YEtyCDR8tOGluHdJgXXLqRJbYc7xmwXciSfZZNT ++0Eug36UOj6y3dR6BGI5Mq3T/rprUxaOjXiLOxeoUPVifsYEtJo9vliiJmUnGa27ZA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794050428; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: MIME-Version:Content-Type:Content-Transfer-Encoding; bh=XbqbFJun+4M8P/XRlznmSVHHc4WbUtUjiOTV2yce58Q=; b=wF0rnjX/1pHF961aG5n65Au6S8Vr8vVaLlrHhjliy5BaVF2dvnomjhQWCeZKVnvNqr/D q9etmAdQqtM4MuirtBgqv7I12USq7ALYaTvUz8fbVZYZadmKYdutl8vkU+LXGfi1w3oGk aji8hgTd/APG378RTTdxaCST8dmu1fo5ySI/c5csuUFpbeD9K0HtzIpR+hyiThMIXhNSV fm5R9S9uhYA1iTvzzNoy3W9Ns0AXcAZgsJWWGR5Z1SapVOLHJgPZIrtZO6nt947YajYHG BaGwbRt+H0KXoBNqt1EG2Yp54ZP8hKagMLdRAcTIJpikyjniAGo1mV1Mt6XDlGnj7AQ== 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=e5mzHUHM; 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 F2743606A326 for ; Sat, 7 Nov 2026 11:20:27 +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=e5mzHUHM Received: by smtp.kernel.org (Postfix) with ESMTPSA id 54CF91F0089F; Sat, 7 Nov 2026 11:20:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794050427; bh=XbqbFJun+4M8P/XRlznmSVHHc4WbUtUjiOTV2yce58Q=; h=From:To:Cc:Subject:Date; b=e5mzHUHMSYYriD4kxtvIwo3bgPCePlw4qVesW3vrWFYJCmCTiRQVc6kog9yFFvrH6 g7qKR7uiote13hyVgxocIi3i3qE2jxRrJ944tPYhCSvcGQdGy+6HCgSOxAVtOiM4Rv NyB2a6jqTHxd1Ue/+KSXpObVWoYHebYkDcRcH3K1CTapCjCjSxBIKvQzjnYn/3D+I1 kUzufT2pQITU5xEspJOTHG+lwN9rgU2TyRtDrItSI9EwijhIrtYJH2CRrAyHEjD1IW e9Gq5EMWQWH3nsooPm3WGmS/j2Ou6z8Qcm/62AZy25T78G1rjC0O9H5XbpDbEQcLaN nmNPstTGzVTsw== From: Sasha Levin To: jesse.zhang@amd.com, christian.koenig@amd.com, arunpravin.paneerselvam@amd.com Cc: stable@vger.kernel.org Subject: FAILED: patch "[PATCH] drm/ttm: return an error when kmapping a BO without pages" failed to apply to 5.10-stable tree Date: Sat, 7 Nov 2026 06:20:25 -0500 Message-ID: <20261107062025-failed-5.10-fd485d47437b@kernel.org> X-Mailer: git-send-email 2.53.0 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 The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y git checkout FETCH_HEAD git cherry-pick -x fd485d47437ba1700dd47205a63b9f389a00aa36 # git commit -s git send-email --to '' --in-reply-to '20261107062025-failed-5.10-fd485d47437b@kernel.org' --subject-prefix 'PATCH 5.10.y' 'HEAD^..' Thanks, Sasha ------------------ original commit in Linus's tree ------------------ >From fd485d47437ba1700dd47205a63b9f389a00aa36 Mon Sep 17 00:00:00 2001 From: Jesse Zhang Date: Fri, 9 Oct 2026 18:33:39 +0800 Subject: [PATCH] drm/ttm: return an error when kmapping a BO without pages MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 --- drivers/gpu/drm/ttm/ttm_bo_util.c | 11 +++++++++-- 1 file 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 bd0b23ac2cc4b..f9458a4d5a09d 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_util.c +++ b/drivers/gpu/drm/ttm/ttm_bo_util.c @@ -356,6 +356,10 @@ 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))) { /* @@ -419,7 +423,7 @@ EXPORT_SYMBOL(ttm_bo_kmap_try_from_panic); * * 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, @@ -493,7 +497,7 @@ EXPORT_SYMBOL(ttm_bo_kunmap); * * 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) { @@ -537,6 +541,9 @@ 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. -- 2.53.0