From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0227AC433F4 for ; Sat, 1 Sep 2018 12:20:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 924E120843 for ; Sat, 1 Sep 2018 12:20:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="ofTEIfGz" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 924E120843 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727352AbeIAQco (ORCPT ); Sat, 1 Sep 2018 12:32:44 -0400 Received: from mail-pg1-f193.google.com ([209.85.215.193]:33482 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726949AbeIAQcn (ORCPT ); Sat, 1 Sep 2018 12:32:43 -0400 Received: by mail-pg1-f193.google.com with SMTP id y3-v6so5403885pgv.0 for ; Sat, 01 Sep 2018 05:20:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=WtPEWrt9G9eyil6yu+3BOjNXbguLNPBLA+11spTOCHU=; b=ofTEIfGzwMVvBgnVmpbN6Tsg8TfuT6p3pAW4ZVmuMwurdrrZEi0s3RCwbfKcMqfgtr 9QAbUqa4ECScTjuTc92jGd6v+R8bhtESEPpGmzCxf4Y0MYS3GtuEpuYL0khY9B2QVAYt NoiSiFpNm3ILGdqoQwF7qWadR9/VCWIkC98brOh1bG/gKthdhU3/jf8IdLMPyGzs5Y2q fRgKeZ5+GDpcrPwZj5UvgOZxUKnw4ZluCJSIbi8FieItFty7a5UzcLex1jp6X6QoeexZ M+ucvMv+XUcVW9E8FMxHtQ3sgFhd6TaVETg4OApW4xMd96IRRyg4jMQ/wrBiZzINqGfs 9Jcw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=WtPEWrt9G9eyil6yu+3BOjNXbguLNPBLA+11spTOCHU=; b=sh5YhF5aUWypCCSUrAk3XiaRmfFUp4T7d4Fm/pi7brXm2WGT+PRZIO7qDH0apfarkf YPfwFS0o0s/XY9mP+/C81Rrhj5tKdFwYpdO9mAs8tur4TmrQW2leGmJrWkGcT/xlqhjr +XVgq6lm32U+iBzcmCS6tewLPrWV8FXjifJYmagdSCAXtfAd5DTSJA52/lMoTrSulJff y4R1LpOIBmlcR8SgcmGqdgC68mnFzZCG28K90l/bGli5MLy9HNQ3T5U+ALFCTVEMRwSI CHb+rp/iAjUl8V9QCvUjShnzrhyLDUaR7RwIA0CuPAkSAUzLs6BDcbhFwnPBD9GeTWNT xalA== X-Gm-Message-State: APzg51BLxhZRYNGzyUFof0gkC+6gf5ad6ZLHgQEQUKry5hUAJ7RVEg6A 5q8y6nO+HNOrqlz5UyWt7zI= X-Google-Smtp-Source: ANB0Vda/n/G1j8emWjQitJJsL1pXqdxCJ3CnKlHPM+sWAhgBuL8PsTVplA9TWW5eGW8IjE1Ujyo4FA== X-Received: by 2002:a62:b0b:: with SMTP id t11-v6mr16630632pfi.36.1535804451889; Sat, 01 Sep 2018 05:20:51 -0700 (PDT) Received: from localhost.localdomain ([2402:f000:1:4414:2913:cd09:aee0:380]) by smtp.gmail.com with ESMTPSA id r81-v6sm18441435pfa.18.2018.09.01.05.20.49 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 01 Sep 2018 05:20:51 -0700 (PDT) From: Jia-Ju Bai To: gustavo@padovan.org, maarten.lankhorst@linux.intel.com, seanpaul@chromium.org, airlied@linux.ie Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH] gpu: drm: drm_mm: Fix a sleep-in-atomic-context bug in show_leaks() Date: Sat, 1 Sep 2018 20:20:41 +0800 Message-Id: <20180901122041.2357-1-baijiaju1990@gmail.com> X-Mailer: git-send-email 2.17.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The driver may sleep with holding a spinlock. The function call paths (from bottom to top) in Linux-4.16 are: [FUNC] kmalloc(GFP_KERNEL) drivers/gpu/drm/drm_mm.c, 130: kmalloc in show_leaks drivers/gpu/drm/drm_mm.c, 913: show_leaks in drm_mm_takedown drivers/gpu/drm/drm_vma_manager.c, 107: drm_mm_takedown in drm_vma_offset_manager_destroy drivers/gpu/drm/drm_vma_manager.c, 106: _raw_write_lock in drm_vma_offset_manager_destroy [FUNC] kmalloc(GFP_KERNEL) drivers/gpu/drm/drm_mm.c, 130: kmalloc in show_leaks drivers/gpu/drm/drm_mm.c, 913: show_leaks in drm_mm_takedown drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c, 71: drm_mm_takedown in amdgpu_vram_mgr_fini drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c, 70: spin_lock in amdgpu_vram_mgr_fini [FUNC] kmalloc(GFP_KERNEL) drivers/gpu/drm/drm_mm.c, 130: kmalloc in show_leaks drivers/gpu/drm/drm_mm.c, 913: show_leaks in drm_mm_takedown drivers/gpu/drm/ttm/ttm_bo_manager.c, 128: drm_mm_takedown in ttm_bo_man_takedown drivers/gpu/drm/ttm/ttm_bo_manager.c, 126: spin_lock in ttm_bo_man_takedown To fix this bug, GFP_KERNEL is replaced with GFP_ATOMIC. This bug is found by my static analysis tool DSAC. Signed-off-by: Jia-Ju Bai --- drivers/gpu/drm/drm_mm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c index 3166026a1874..2486121a78d4 100644 --- a/drivers/gpu/drm/drm_mm.c +++ b/drivers/gpu/drm/drm_mm.c @@ -127,7 +127,7 @@ static void show_leaks(struct drm_mm *mm) unsigned long entries[STACKDEPTH]; char *buf; - buf = kmalloc(BUFSZ, GFP_KERNEL); + buf = kmalloc(BUFSZ, GFP_ATOMIC); if (!buf) return; -- 2.17.0