From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4CFDB572679; Wed, 9 Sep 2026 14:31:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788964280; cv=none; b=DsfT8ZIGsMOZInG4tDwZciHcqdwHoDB0KiDPf41mma8FCOrfrkoquGQquSE4jDNnyvYmYQsRCIDfSdVKTkRqHMVm3T1MVezbv57UiPq4+NwwCiHfidqbXFEHck87FrcxK2d/RNFKBmLfLocNjfoKpN7u0kiYltwNcV9ofWiShmQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788964280; c=relaxed/simple; bh=Z6OmfKgrCRPwP4kwEfEYIRTaKsR9RNBGX1kdW3CBN6E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=La+JvkO5wG3/RDnZzsqmvDy58INOppxYX3zZFP7TbivfMfuRH43toBH3tDiOPjCmKyPFWxBGxsz1Dwmj0MLwaromt3e1IB66YMfWQcazU4qGaSUyox2K4OLz5WzSShuO3QXHRxiw+bIdKK0aAflf4lrnFi5CKZmsphjR6+iA6uU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Xg2yRwGL; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Xg2yRwGL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A0AD31F00A3A; Wed, 9 Sep 2026 14:31:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788964278; bh=RbvPw3lfH5o8LagbXAjtXsF2tsvxyuqQXuNXLYtGurI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Xg2yRwGLLMQubp9puykB06085OJ9ySQ1uX2TMg+gwhPUu+fwg38TELbLaj33uPfYh /5esViOFKH2U1sjPFYFcr4v6Yco30w4BdAtiV+vfKrXcRvwUg2fbVa5t1VVgJR/Urm BvSJoqh/+zZ5+BH9CwIrkVIb1subZ3U1FyvInofQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sashiko-bot , Friedrich Vock , Maarten Lankhorst , Tejun Heo , Maxime Ripard , =?UTF-8?q?Christian=20K=C3=B6nig?= , Alex Deucher , amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= , Arunpravin Paneer Selvam , Maarten Lankhorst , Thadeu Lima de Souza Cascardo Subject: [PATCH 6.18 369/583] drm/amdgpu: Fix init ordering in amdgpu_vram_mgr_init() Date: Wed, 9 Sep 2026 15:40:54 +0200 Message-ID: <20260909134250.818813896@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260909134237.773280130@linuxfoundation.org> References: <20260909134237.773280130@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Thomas Hellström commit e773798e14ac0aea54ca9676083b91f445e5bc59 upstream. drmm_cgroup_register_region() is called before INIT_LIST_HEAD() and gpu_buddy_init() in amdgpu_vram_mgr_init(). If it fails, the function returns early and bypasses those initializations. Since adev->mman.initialized is set to true before amdgpu_vram_mgr_init() is called, a failure triggers amdgpu_ttm_fini(), which calls amdgpu_vram_mgr_fini(), which then: - Calls list_for_each_entry_safe() on reservations_pending and reserved_pages, whose list_head::next pointers are zero-initialized (NULL). The loop does not recognize them as empty and dereferences NULL. - Calls gpu_buddy_fini(), which iterates free_trees[] unconditionally via for_each_free_tree(). Since mm->free_trees is NULL (never allocated), this dereferences NULL. Both result in a kernel panic on the module load error path. Fix by moving drmm_cgroup_register_region() to after the list and buddy allocator are fully initialized, so the teardown path is safe to run. Reported-by: Sashiko-bot Closes: https://sashiko.dev/#/patchset/20260428073116.15687-1-thomas.hellstrom@linux.intel.com?part=4 Fixes: 2b624a2c1865 ("drm/ttm: Handle cgroup based eviction in TTM") Cc: Friedrich Vock Cc: Maarten Lankhorst Cc: Tejun Heo Cc: Maxime Ripard Cc: Christian König Cc: Alex Deucher Cc: amd-gfx@lists.freedesktop.org Cc: dri-devel@lists.freedesktop.org Cc: stable@vger.kernel.org # v6.14+ Assisted-by: GitHub_Copilot:claude-sonnet-4.6 Signed-off-by: Thomas Hellström Reviewed-by: Arunpravin Paneer Selvam Reviewed-By: Maarten Lankhorst Tested-by: Thadeu Lima de Souza Cascardo Link: https://patch.msgid.link/20260725100036.2372-2-thomas.hellstrom@linux.intel.com Acked-by: Christian König Signed-off-by: Maarten Lankhorst Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c @@ -918,9 +918,6 @@ int amdgpu_vram_mgr_init(struct amdgpu_d struct ttm_resource_manager *man = &mgr->manager; int err; - man->cg = drmm_cgroup_register_region(adev_to_drm(adev), "vram", adev->gmc.real_vram_size); - if (IS_ERR(man->cg)) - return PTR_ERR(man->cg); ttm_resource_manager_init(man, &adev->mman.bdev, adev->gmc.real_vram_size); @@ -935,6 +932,10 @@ int amdgpu_vram_mgr_init(struct amdgpu_d if (err) return err; + man->cg = drmm_cgroup_register_region(adev_to_drm(adev), "vram", adev->gmc.real_vram_size); + if (IS_ERR(man->cg)) + return PTR_ERR(man->cg); + ttm_set_driver_manager(&adev->mman.bdev, TTM_PL_VRAM, &mgr->manager); ttm_resource_manager_set_used(man, true); return 0;