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=1794048380; b=hAKnmzuxDGzsQNlAamouNTP1MdknWLRc27zUWow+xp9oz5ohaSYuqdILW5GllIZmD22k xU0LWACfYhbzTi4DCSbfIOsrmP06MJPNBezwQuu3bl9lg2s9wZSRRbbVLbRbGACakWrMW DFbVC8Jvw899KXy9ylRLIyH2moE8FHDItCaZ6SgLmBtpVxFukJ7q2EdK6uPiMIGiWI5Ft BbGfhXA8H1XQZllwGbQToQV8JXBM8WRgCC1ZapP+shqzXctSLFovcsYreEeGHektH5a+y GiN8LHDtlULsPoOUKrTYB3yB9boDkyyvr1TE5HLvYoSnxjN/hjyzxVwpPhcVBar8r5A== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794048380; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: MIME-Version:Content-Type:Content-Transfer-Encoding; bh=Om/PMZppHyZlUoSVY1KwU2Uqa5p7xLaexa63JcfnGT4=; b=ycx6ovKqRcOcdx5vQWx7xML0KQmR33HRjYYeBQYrSL7Ln0rkZ/GO3WZJ1QZoPhK/Mf5t GB7J6RJnLjAEUtsoPltQTJKl3b20sC5ZBKBrIqUz85fL7stZocQpeFadovUwYr36yuLsV prDGyX8OFL2wvfx1ykeU0FaItmOJGRc/p3ueqJoRp3WFptxUfBDidJg7PTshHJkaml0Kk HCin/AN0lNuh0G7/eIBVg2YpNM33wGBDmEWksctnIMbM9ezmSCz0IoM0Ap8H12FLX/Ii2 g0lz+h4hIZebYOOGKGSLsLMuiC/Z0/fz2xBKdfZ2DbpmGcBEN6dCgoho9zvjkPXxExg== 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=OLZw0N5Y; 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 07398606A32C for ; Sat, 7 Nov 2026 10:46:20 +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=OLZw0N5Y Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5EA4A1F0089F; Sat, 7 Nov 2026 10:46:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794048379; bh=Om/PMZppHyZlUoSVY1KwU2Uqa5p7xLaexa63JcfnGT4=; h=From:To:Cc:Subject:Date; b=OLZw0N5YZRQE6y4+85PcG0CuvsLzwdRVH5HV8uFN15ciyf8AMy/rWHnafjjvUXY9I EtYws/CmKgrzKWT0dhlXjjh7Ey5jwBulF6pjWFjJPAtq1m4ePnCW1D4PNgPAxe08+p E9ctMi9IBKsyXkxZPR1WTKluEw3ywAifO3JgXsnFZ+XYqTIY1rxM5T85UysjWH5Qo4 +oJVGPv33ZYSS8kYe4AymbrUjKWYPXAVekARjCtrnlr5rt8sTS/Om5GRvnxbXi9z4w dQtRQbP4l87bhMqgmoemV3rL+jJ7OIxHaPvBUYbcy6t/bTsgHun95RynjzaNhbbUAv J9GGfp2RPFdKQ== 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 6.1-stable tree Date: Sat, 7 Nov 2026 05:46:18 -0500 Message-ID: <20261107054617-failed-6.1-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 6.1-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-6.1.y git checkout FETCH_HEAD git cherry-pick -x fd485d47437ba1700dd47205a63b9f389a00aa36 # git commit -s git send-email --to '' --in-reply-to '20261107054617-failed-6.1-fd485d47437b@kernel.org' --subject-prefix 'PATCH 6.1.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