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=-11.5 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, NICE_REPLY_A,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 B94FFC43457 for ; Sat, 10 Oct 2020 23:45:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 795522074F for ; Sat, 10 Oct 2020 23:45:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="WkFLdINm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387399AbgJJXpT (ORCPT ); Sat, 10 Oct 2020 19:45:19 -0400 Received: from z5.mailgun.us ([104.130.96.5]:34650 "EHLO z5.mailgun.us" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387568AbgJJXpS (ORCPT ); Sat, 10 Oct 2020 19:45:18 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1602373518; h=Content-Transfer-Encoding: Content-Type: In-Reply-To: MIME-Version: Date: Message-ID: From: References: Cc: To: Subject: Sender; bh=+sjzZxdSz1OxaSjQtFwsicElknUm3wlBG4uyjUVXudw=; b=WkFLdINm/oGrPiIOTR9GSmtKRcvvEmOSDfkTF9ESSpnbXS+MmAVynel+3kcz7NmPhGvEAr5Z SbP86hwP1FjfNGNYWq/U8s1HnKb/J6DPkeu/sWRtlmx2yqt4qNyu4y3lsQmwf2jyi0KwtP+f vjs6MpUMhMyTr51UGh05Lb0o+YQ= X-Mailgun-Sending-Ip: 104.130.96.5 X-Mailgun-Sid: WyI1MzIzYiIsICJsaW51eC1hcm0tbXNtQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n04.prod.us-west-2.postgun.com with SMTP id 5f824783856d9308b5e16c82 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Sat, 10 Oct 2020 23:45:07 GMT Sender: mgautam=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id A2DC9C433FF; Sat, 10 Oct 2020 23:45:07 +0000 (UTC) Received: from [192.168.1.8] (unknown [223.230.69.105]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: mgautam) by smtp.codeaurora.org (Postfix) with ESMTPSA id 230EAC433C9; Sat, 10 Oct 2020 23:45:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 230EAC433C9 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=mgautam@codeaurora.org Subject: Re: [PATCH v1 05/10] bus: mhi: core: Disable IRQs when powering down To: Bhaumik Bhatt , manivannan.sadhasivam@linaro.org Cc: linux-arm-msm@vger.kernel.org, hemantk@codeaurora.org, jhugo@codeaurora.org, linux-kernel@vger.kernel.org References: <1600480955-16827-1-git-send-email-bbhatt@codeaurora.org> <1600480955-16827-6-git-send-email-bbhatt@codeaurora.org> From: Manu Gautam Message-ID: <2c77a164-db22-16c8-ebce-21a028fc1ed6@codeaurora.org> Date: Sun, 11 Oct 2020 05:15:00 +0530 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <1600480955-16827-6-git-send-email-bbhatt@codeaurora.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Hi On 9/19/2020 7:32 AM, Bhaumik Bhatt wrote: > While powering down, the device may or may not acknowledge the MHI > RESET issued by host for graceful shutdown scenario which can lead > to a rogue device sending an interrupt after the clean-up has been > done. This can result in a tasklet being scheduled after it has > been killed and access already freed memory causing a NULL pointer > exception. Avoid this corner case by disabling the interrupts as a > part of host clean up. > > Signed-off-by: Bhaumik Bhatt > --- > drivers/bus/mhi/core/pm.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c > index 1862960..3462d82 100644 > --- a/drivers/bus/mhi/core/pm.c > +++ b/drivers/bus/mhi/core/pm.c > @@ -517,6 +517,7 @@ static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl, > for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) { > if (mhi_event->offload_ev) > continue; > + disable_irq(mhi_cntrl->irq[mhi_event->irq]); > tasklet_kill(&mhi_event->task); > } > What about sys_err handling? IRQ may be left disabled? -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project