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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9CA54C433EF for ; Fri, 3 Jun 2022 09:44:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243148AbiFCJoq (ORCPT ); Fri, 3 Jun 2022 05:44:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38776 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243141AbiFCJoo (ORCPT ); Fri, 3 Jun 2022 05:44:44 -0400 Received: from mail-lf1-x12f.google.com (mail-lf1-x12f.google.com [IPv6:2a00:1450:4864:20::12f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 83DC22DD54 for ; Fri, 3 Jun 2022 02:44:42 -0700 (PDT) Received: by mail-lf1-x12f.google.com with SMTP id u23so11794040lfc.1 for ; Fri, 03 Jun 2022 02:44:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=8jvPxXIiogQWZXupdX922CHoFednIGVLXVXf4QrHgiY=; b=O+UOlhaU1GPM2ffiLXlaOOMPGwOgfFKeYFBHms9Z8euUAUJMN780YC1U5nRTDDWGQ3 4P1TMXkIg2nzQtv6Tp1TuxJ/QINIw9PazrWgt5IE0uzXCGT4o6iBDE+S1po2vLqoq3r4 7ApFEsva8AT52NIR0mH/mDjoj+t6A9cC9bVtOjeWL6jZQXMk0IhxlpxdKx5PaBA9AFAB WHHcjMLbejA1cwApeH1b+djfmVvnhn54wv07zDj3HIt/13AEeHqWo9v3tIUpfATBwWhR M0ZzrA69wATnpkeRmnXLyhcvM72dUyL3htH+LN21JM2qsIchR9JbZpJZa9JUBMgfsbD7 a/xw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=8jvPxXIiogQWZXupdX922CHoFednIGVLXVXf4QrHgiY=; b=RYVJeeKuLYupEFeE6j6Q8P5knS7Lsk8tc8bD9Lb2EUg6SKw4B7m6L1u3W8SAwYv/QK aAUHlM/jByZowvsxyiLx902hqRLjOjIOEqx2k1SCCgbKauStZDKmEXH70ROQPTWozMvU /vUNk3odVnz8uzZK7usmfIkJkMorW+yhClPnLn3Ul3ioy5GJmAn06+wbNxN66pnnZJM/ 1avA3ygwCvuHEwP3On4GS5xf4DkRAHcDB+kKop8rAcSguCjXyEKnbipc7htjoXrtUQCi NKzqlKAli1tXXPruQGWY2dHHLYvprThSCeG9BekMjg7/hNe8D3aHhYBlbWKGSBIz9ReQ qSNg== X-Gm-Message-State: AOAM533TDP6lL+RUCF5nl6H6tVqtPsZBA/bWUF6OHC44lFEqrJ6oJBjN gSlDXJy9FSJdp2F6+l9E5kiquQ== X-Google-Smtp-Source: ABdhPJyZegfaWSTXswsrJxcn+pcCQNNZ/clp5ept6GyUSg+T+X/U1x6nsEJb4dwGWdJLV5++QVgCPw== X-Received: by 2002:a05:6512:2115:b0:479:ba9:25c1 with SMTP id q21-20020a056512211500b004790ba925c1mr6124265lfr.591.1654249480917; Fri, 03 Jun 2022 02:44:40 -0700 (PDT) Received: from [192.168.1.211] ([37.153.55.125]) by smtp.gmail.com with ESMTPSA id e29-20020a19691d000000b0047255d21202sm1397159lfc.305.2022.06.03.02.44.40 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 03 Jun 2022 02:44:40 -0700 (PDT) Message-ID: <9e398930-6918-e95e-e15d-f8901047b9b7@linaro.org> Date: Fri, 3 Jun 2022 12:44:39 +0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.0 Subject: Re: [v2] drm/msm: add null checks for drm device to avoid crash during probe defer Content-Language: en-GB To: Vinod Polimera , dri-devel@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org, devicetree@vger.kernel.org Cc: linux-kernel@vger.kernel.org, robdclark@gmail.com, dianders@chromium.org, vpolimer@quicinc.com, swboyd@chromium.org, kalyant@quicinc.com References: <1654249343-24959-1-git-send-email-quic_vpolimer@quicinc.com> From: Dmitry Baryshkov In-Reply-To: <1654249343-24959-1-git-send-email-quic_vpolimer@quicinc.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On 03/06/2022 12:42, Vinod Polimera wrote: > During probe defer, drm device is not initialized and an external > trigger to shutdown is trying to clean up drm device leading to crash. > Add checks to avoid drm device cleanup in such cases. > > BUG: unable to handle kernel NULL pointer dereference at virtual > address 00000000000000b8 > > Call trace: > > drm_atomic_helper_shutdown+0x44/0x144 > msm_pdev_shutdown+0x2c/0x38 > platform_shutdown+0x2c/0x38 > device_shutdown+0x158/0x210 > kernel_restart_prepare+0x40/0x4c > kernel_restart+0x20/0x6c > __arm64_sys_reboot+0x194/0x23c > invoke_syscall+0x50/0x13c > el0_svc_common+0xa0/0x17c > do_el0_svc_compat+0x28/0x34 > el0_svc_compat+0x20/0x70 > el0t_32_sync_handler+0xa8/0xcc > el0t_32_sync+0x1a8/0x1ac > > Changes in v2: > - Add fixes tag. I'm still waiting for an answer to the questions raised in v1 review. > > Fixes: 623f279c778 ("drm/msm: fix shutdown hook in case GPU components failed to bind") > Signed-off-by: Vinod Polimera > --- > drivers/gpu/drm/msm/msm_drv.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c > index 4448536..d62ac66 100644 > --- a/drivers/gpu/drm/msm/msm_drv.c > +++ b/drivers/gpu/drm/msm/msm_drv.c > @@ -142,6 +142,9 @@ static void msm_irq_uninstall(struct drm_device *dev) > struct msm_drm_private *priv = dev->dev_private; > struct msm_kms *kms = priv->kms; > > + if (!irq_has_action(kms->irq)) > + return; > + > kms->funcs->irq_uninstall(kms); > if (kms->irq_requested) > free_irq(kms->irq, dev); > @@ -259,6 +262,7 @@ static int msm_drm_uninit(struct device *dev) > > ddev->dev_private = NULL; > drm_dev_put(ddev); > + priv->dev = NULL; > > destroy_workqueue(priv->wq); > > @@ -1167,7 +1171,7 @@ void msm_drv_shutdown(struct platform_device *pdev) > struct msm_drm_private *priv = platform_get_drvdata(pdev); > struct drm_device *drm = priv ? priv->dev : NULL; > > - if (!priv || !priv->kms) > + if (!priv || !priv->kms || !drm) > return; > > drm_atomic_helper_shutdown(drm); -- With best wishes Dmitry