From patchwork Tue Feb 11 03:40:48 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Can Guo X-Patchwork-Id: 11374801 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B0E91138D for ; Tue, 11 Feb 2020 03:41:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 913D22082F for ; Tue, 11 Feb 2020 03:41:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="fbQBJAf2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728083AbgBKDl2 (ORCPT ); Mon, 10 Feb 2020 22:41:28 -0500 Received: from mail25.static.mailgun.info ([104.130.122.25]:25144 "EHLO mail25.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728077AbgBKDl2 (ORCPT ); Mon, 10 Feb 2020 22:41:28 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1581392487; h=References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=mOGsKpB2Al28vMrBa0jcYjVjoj+5dd6cChtWkiROc10=; b=fbQBJAf20+HXcDpuPu6bfpxj8WuU9+ijP5zz2ybJCKrelgAyw7Uc8ZgpWtAdjI6bdo+VbDYH zYn/xfp4eJDDgTnUhhJmVIZeQoPIqLK7aS+4r/zsOBAfWZEqKkLR9I+4BJ+gGOILTgrYfvf4 Pgp4II26mlRHFgWoJ0OV1LGESXk= X-Mailgun-Sending-Ip: 104.130.122.25 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 mxa.mailgun.org with ESMTP id 5e422262.7ff4d13afc70-smtp-out-n01; Tue, 11 Feb 2020 03:41:22 -0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 271F9C447AA; Tue, 11 Feb 2020 03:41:20 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-caf-mail-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=2.0 tests=ALL_TRUSTED,SPF_NONE, URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from pacamara-linux.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: cang) by smtp.codeaurora.org (Postfix) with ESMTPSA id 876B4C43383; Tue, 11 Feb 2020 03:41:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 876B4C43383 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=none smtp.mailfrom=cang@codeaurora.org From: Can Guo To: asutoshd@codeaurora.org, nguyenb@codeaurora.org, hongwus@codeaurora.org, rnayak@codeaurora.org, linux-scsi@vger.kernel.org, kernel-team@android.com, saravanak@google.com, salyzyn@google.com, cang@codeaurora.org Cc: Alim Akhtar , Avri Altman , "James E.J. Bottomley" , "Martin K. Petersen" , Matthias Brugger , Subhash Jadavani , Venkat Gopalakrishnan , Bean Huo , Stanley Chu , Bart Van Assche , Tomas Winkler , linux-kernel@vger.kernel.org (open list), linux-arm-kernel@lists.infradead.org (moderated list:ARM/Mediatek SoC support), linux-mediatek@lists.infradead.org (moderated list:ARM/Mediatek SoC support) Subject: [PATCH v10 5/7] scsi: ufs: Fix ufshcd_hold() caused scheduling while atomic Date: Mon, 10 Feb 2020 19:40:48 -0800 Message-Id: <1581392451-28743-6-git-send-email-cang@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1581392451-28743-1-git-send-email-cang@codeaurora.org> References: <1581392451-28743-1-git-send-email-cang@codeaurora.org> Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org The async version of ufshcd_hold(async == true), which is only called in queuecommand path as for now, is expected to work in atomic context, thus it should not sleep or schedule out. When it runs into the condition that clocks are ON but link is still in hibern8 state, it should bail out without flushing the clock ungate work. Fixes: f2a785ac2312 ("scsi: ufshcd: Fix race between clk scaling and ungate work") Signed-off-by: Can Guo Reviewed-by: Hongwu Su Reviewed-by: Asutosh Das Reviewed-by: Bean Huo Reviewed-by: Stanley Chu --- drivers/scsi/ufs/ufshcd.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index bbc2607..e8f7f9d 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -1518,6 +1518,11 @@ int ufshcd_hold(struct ufs_hba *hba, bool async) */ if (ufshcd_can_hibern8_during_gating(hba) && ufshcd_is_link_hibern8(hba)) { + if (async) { + rc = -EAGAIN; + hba->clk_gating.active_reqs--; + break; + } spin_unlock_irqrestore(hba->host->host_lock, flags); flush_work(&hba->clk_gating.ungate_work); spin_lock_irqsave(hba->host->host_lock, flags);