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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4658AC433F5 for ; Fri, 8 Oct 2021 16:41:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2324560F9C for ; Fri, 8 Oct 2021 16:41:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230301AbhJHQmy (ORCPT ); Fri, 8 Oct 2021 12:42:54 -0400 Received: from m43-7.mailgun.net ([69.72.43.7]:52023 "EHLO m43-7.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229606AbhJHQmy (ORCPT ); Fri, 8 Oct 2021 12:42:54 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1633711259; h=Content-Transfer-Encoding: Content-Type: In-Reply-To: From: References: Cc: To: Subject: MIME-Version: Date: Message-ID: Sender; bh=kHfDDgR5llcD5oBuqF26xeoc++cr4Itq9Lj0qxdQCdY=; b=YUoD+1c4qQ862bHrx179tS+pC7fKnGeceikEI9fBRjJZn0fTMEgxcMHAFQWGv/MchQhixkIN IA9z28SrORjcEb+YY6v7M1Gv4EJztQMZp2sWkIPoYDRg6iNCVayBOQFEUpUStnyUNQoFAGy7 JkNIkdfv84gYPD7ncY8pPwNbQ5Y= X-Mailgun-Sending-Ip: 69.72.43.7 X-Mailgun-Sid: WyJlNmU5NiIsICJsaW51eC1zY3NpQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== 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-east-1.postgun.com with SMTP id 61607494ab9da96e647d5f03 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Fri, 08 Oct 2021 16:40:52 GMT Sender: asutoshd=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 2DCE8C4361C; Fri, 8 Oct 2021 16:40:51 +0000 (UTC) Received: from [10.71.115.70] (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: asutoshd) by smtp.codeaurora.org (Postfix) with ESMTPSA id A992FC4338F; Fri, 8 Oct 2021 16:40:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 smtp.codeaurora.org A992FC4338F 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=codeaurora.org Message-ID: <374d943a-dadf-51e0-ebf1-a3d3db4c4e0c@codeaurora.org> Date: Fri, 8 Oct 2021 09:40:49 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.1.0 Subject: Re: [PATCH V2] scsi: ufs: core: Fix synchronization between scsi_unjam_host() and ufshcd_queuecommand() To: Adrian Hunter , "Martin K . Petersen" Cc: "James E . J . Bottomley" , Bean Huo , Avri Altman , Alim Akhtar , Can Guo , Bart Van Assche , linux-scsi@vger.kernel.org References: <20211008084048.257498-1-adrian.hunter@intel.com> From: "Asutosh Das (asd)" In-Reply-To: <20211008084048.257498-1-adrian.hunter@intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org On 10/8/2021 1:40 AM, Adrian Hunter wrote: > The SCSI error handler calls scsi_unjam_host() which can call the queue > function ufshcd_queuecommand() indirectly. The error handler changes the > state to UFSHCD_STATE_RESET while running, but error interrupts that > happen while the error handler is running could change the state to > UFSHCD_STATE_EH_SCHEDULED_NON_FATAL which would allow requests to go > through ufshcd_queuecommand() even though the error handler is running. > Block that hole by checking whether the error handler is in progress. > > Signed-off-by: Adrian Hunter > --- LGTM. Reviewed-by: Asutosh Das > > Changes in V2: > > Add comment > > drivers/scsi/ufs/ufshcd.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c > index f34227add27d..29d202207b18 100644 > --- a/drivers/scsi/ufs/ufshcd.c > +++ b/drivers/scsi/ufs/ufshcd.c > @@ -2688,7 +2688,19 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd) > > switch (hba->ufshcd_state) { > case UFSHCD_STATE_OPERATIONAL: > + break; > case UFSHCD_STATE_EH_SCHEDULED_NON_FATAL: > + /* > + * SCSI error handler can call ->queuecommand() while UFS error > + * handler is in progress. Error interrupts could change the > + * state from UFSHCD_STATE_RESET to > + * UFSHCD_STATE_EH_SCHEDULED_NON_FATAL. Prevent requests > + * being issued in that case. > + */ > + if (ufshcd_eh_in_progress(hba)) { > + err = SCSI_MLQUEUE_HOST_BUSY; > + goto out; > + } > break; > case UFSHCD_STATE_EH_SCHEDULED_FATAL: > /* > -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, Linux Foundation Collaborative Project