From patchwork Tue Feb 11 02:37:47 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Can Guo X-Patchwork-Id: 11374687 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 5A09392A for ; Tue, 11 Feb 2020 02:38:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3AAD720842 for ; Tue, 11 Feb 2020 02:38:33 +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="mv788gzx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727937AbgBKCiZ (ORCPT ); Mon, 10 Feb 2020 21:38:25 -0500 Received: from mail26.static.mailgun.info ([104.130.122.26]:19969 "EHLO mail26.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727878AbgBKCiY (ORCPT ); Mon, 10 Feb 2020 21:38:24 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1581388704; h=References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=mOGsKpB2Al28vMrBa0jcYjVjoj+5dd6cChtWkiROc10=; b=mv788gzxaJjqc7pI6da9lBr303kmluA4bM+IU6/6zQnSbM7iRqTaEKru7RmKElUaf8gKBXOl lZYKmex8YFm3AlQpa5e6on71vb8FSD6TJPuSAsfNg0WSx+wOuDP00sdQdUTPKVzGoduc8gPa /chy7uH+uIf8wK4H+cARwPCQcn0= X-Mailgun-Sending-Ip: 104.130.122.26 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 5e42139f.7f42efef85a8-smtp-out-n03; Tue, 11 Feb 2020 02:38:23 -0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 6DD80C4479D; Tue, 11 Feb 2020 02:38:21 +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 60794C43383; Tue, 11 Feb 2020 02:38:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 60794C43383 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 , Venkat Gopalakrishnan , Subhash Jadavani , 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 v9 5/7] scsi: ufs: Fix ufshcd_hold() caused scheduling while atomic Date: Mon, 10 Feb 2020 18:37:47 -0800 Message-Id: <1581388671-18078-6-git-send-email-cang@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1581388671-18078-1-git-send-email-cang@codeaurora.org> References: <1581388671-18078-1-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);