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=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,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 70EDEC43460 for ; Fri, 30 Apr 2021 08:27:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2E3C76140C for ; Fri, 30 Apr 2021 08:27:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231349AbhD3I2k (ORCPT ); Fri, 30 Apr 2021 04:28:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51568 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229529AbhD3I2j (ORCPT ); Fri, 30 Apr 2021 04:28:39 -0400 Received: from mail-wr1-x432.google.com (mail-wr1-x432.google.com [IPv6:2a00:1450:4864:20::432]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1EF92C06174A for ; Fri, 30 Apr 2021 01:27:50 -0700 (PDT) Received: by mail-wr1-x432.google.com with SMTP id t18so12008262wry.1 for ; Fri, 30 Apr 2021 01:27:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=x12D1fSgMXo84/StrNDXFY95BOlA8w3dEtySPm5wCgQ=; b=q5RkY2TEzEE6oWZZbW+87d2glkkz6bArkK6G7aeyOTL/H6i5S97xaGLHvQ7feTUwKC 1yaM5gV/avDemn8LUsrGG4ttN8Njingl5hDQcXiFweWa77q5BSlgh8DTBXxWlaQQXQ4k r1lSJznmcSEPRoyRX6erX7SDkpU6d2SLI6M8bWaGqGtY1ruPepci6ZZIwFNRYe5YKJa3 yjAHDDUPwDNtlN2+gWew99O3ATqgPaq1drQVwYnfKrBxevD6IPejzjmuF6NGbn7gSLsS uOmK0IYiYEIpsf4jXL+Yqb+Qsa02G5V/KRmeYGuii/TEAavD6FHr3X7gsIieEtzPeQj7 wX1g== 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:mime-version :content-transfer-encoding; bh=x12D1fSgMXo84/StrNDXFY95BOlA8w3dEtySPm5wCgQ=; b=hQbOyuctWD3tLLc5UTS3P/gt3Q2fjtM1x34QmKB71HojNBSqx2FaQRptQ3ovXxMRqc ulxRgfIjS7v+GFJC2tK5MFJIgCR11crVnnp2Jf2Tq5MET9q9uiIWSquyCj4UphijcBK5 mxLJAK4tb7AJByC4QgF6YkSWu0BgtRHiX0OjPEgHh45rOe9enjOYEjk0TY9wnleIlewY WHsorpC2IMoHtfoypajXKUMZBM9UC+FgKtqJXuOmEbfXP3zwLmzeJsRysvCGwDy1k8tp voucv/38ivdxT/ktQiUhIcxspvH0TN5sLuLePKa7geS/4mYRlxSFH37SQc7eGjC3iW0i soWQ== X-Gm-Message-State: AOAM533A48QvxNOQRqPDtDmQT/ul6FiQyEhrPbYrAt/DcaQeAuNOCXCS M7yTiYwZuRXbaeQctCoxjw/ADD9IJR46n2Qk X-Google-Smtp-Source: ABdhPJxGoyaka1SwUgXjXPuWPXVdSHHYtgAfq3tVpjG7MANHxCuZPbgUWnsHDmVM463gHiGYmCPtyg== X-Received: by 2002:adf:efca:: with SMTP id i10mr1630979wrp.284.1619771268768; Fri, 30 Apr 2021 01:27:48 -0700 (PDT) Received: from localhost.localdomain ([2a01:e0a:90c:e290:4a89:8c32:4adc:fc67]) by smtp.gmail.com with ESMTPSA id e12sm1336677wrt.51.2021.04.30.01.27.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 30 Apr 2021 01:27:47 -0700 (PDT) From: Neil Armstrong To: dri-devel@lists.freedesktop.org Cc: linux-amlogic@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Neil Armstrong , Stefan Agner Subject: [PATCH] drm/meson: fix shutdown crash when component not probed Date: Fri, 30 Apr 2021 10:27:44 +0200 Message-Id: <20210430082744.3638743-1-narmstrong@baylibre.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When main component is not probed, by example when the dw-hdmi module is not loaded yet or in probe defer, the following crash appears on shutdown: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000038 ... pc : meson_drv_shutdown+0x24/0x50 lr : platform_drv_shutdown+0x20/0x30 ... Call trace: meson_drv_shutdown+0x24/0x50 platform_drv_shutdown+0x20/0x30 device_shutdown+0x158/0x360 kernel_restart_prepare+0x38/0x48 kernel_restart+0x18/0x68 __do_sys_reboot+0x224/0x250 __arm64_sys_reboot+0x24/0x30 ... Simply check if the priv struct has been allocated before using it. Fixes: fa0c16caf3d7 ("drm: meson_drv add shutdown function") Reported-by: Stefan Agner Signed-off-by: Neil Armstrong --- drivers/gpu/drm/meson/meson_drv.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/meson/meson_drv.c b/drivers/gpu/drm/meson/meson_drv.c index 453d8b4c5763..07fcd12dca16 100644 --- a/drivers/gpu/drm/meson/meson_drv.c +++ b/drivers/gpu/drm/meson/meson_drv.c @@ -485,11 +485,12 @@ static int meson_probe_remote(struct platform_device *pdev, static void meson_drv_shutdown(struct platform_device *pdev) { struct meson_drm *priv = dev_get_drvdata(&pdev->dev); - struct drm_device *drm = priv->drm; - DRM_DEBUG_DRIVER("\n"); - drm_kms_helper_poll_fini(drm); - drm_atomic_helper_shutdown(drm); + if (!priv) + return; + + drm_kms_helper_poll_fini(priv->drm); + drm_atomic_helper_shutdown(priv->drm); } static int meson_drv_probe(struct platform_device *pdev) -- 2.25.1