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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 A2E0AC55186 for ; Wed, 22 Apr 2020 10:50:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 699C32073A for ; Wed, 22 Apr 2020 10:50:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587552610; bh=+SrwVG1wkcsfrVwkbz4KAAKDbgLeN74p2Cc+qM20LlY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Wo+R1rQcs4WGh08CDhUfwFhxrGfMY9z8quaQ0qiTpyFenyfShSI6dQF142DBhLd9u NCdpBU82pE/UiYc6SAHjYGIN5Yl2Gc89SdrXGunIF6VgQoTxyaQDpctsr/7kZFuuTk oZzPmfYSsnKUyW4465VB30RXPmUVyhyn5fIc0TLA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729363AbgDVKMt (ORCPT ); Wed, 22 Apr 2020 06:12:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:45692 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728769AbgDVKMe (ORCPT ); Wed, 22 Apr 2020 06:12:34 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 98EC920575; Wed, 22 Apr 2020 10:12:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587550354; bh=+SrwVG1wkcsfrVwkbz4KAAKDbgLeN74p2Cc+qM20LlY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Z7ujgR5POl3x7EgGWVGDs12FjtwdWUi+WDGYivKJ36FNspu4sfgO7msb5+cGQdg0O I/dMw+i/8LZAVX2ofCsONkuzpEsD8FHcREy0xb59UAzDikWT2fnfAfa0iKyLboduI+ s7JBVINHM4EUtoRxlZIrjnZk8hiKTW20T6+BO/LA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hongwu Su , Asutosh Das , Bean Huo , Stanley Chu , Can Guo , "Martin K. Petersen" Subject: [PATCH 4.14 113/199] scsi: ufs: Fix ufshcd_hold() caused scheduling while atomic Date: Wed, 22 Apr 2020 11:57:19 +0200 Message-Id: <20200422095108.968120627@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200422095057.806111593@linuxfoundation.org> References: <20200422095057.806111593@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Can Guo commit c63d6099a7959ecc919b2549dc6b71f53521f819 upstream. 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") Link: https://lore.kernel.org/r/1581392451-28743-6-git-send-email-cang@codeaurora.org Reviewed-by: Hongwu Su Reviewed-by: Asutosh Das Reviewed-by: Bean Huo Reviewed-by: Stanley Chu Signed-off-by: Can Guo Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman --- drivers/scsi/ufs/ufshcd.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -1448,6 +1448,11 @@ start: */ 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);