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,USER_AGENT_GIT 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 18D1DC54FD0 for ; Mon, 20 Apr 2020 12:40:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E2249206D4 for ; Mon, 20 Apr 2020 12:40:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587386441; bh=RO1VvA0TedKY/5ElciEG/QJ0CF/7C7PmxxWIipvdjA0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=SX/OOXOwmDDT1Kkr5q1m3plzv28ryH8gm+Z4bn76DJrEzPFqNQSnpcZpvnEFkBpeu 2k7yN1eOwQb7+rMtSfT//DtXWQjfp2Sg098QUbkBUWHioydd/giPnduzwBUvAHI8ov 0X50pkict7ahX4YlE6o15eql1n29KS45eO2Qk3vc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727813AbgDTMkk (ORCPT ); Mon, 20 Apr 2020 08:40:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:32912 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727780AbgDTMki (ORCPT ); Mon, 20 Apr 2020 08:40:38 -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 DD14020736; Mon, 20 Apr 2020 12:40:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587386437; bh=RO1VvA0TedKY/5ElciEG/QJ0CF/7C7PmxxWIipvdjA0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=C+QKAk6hYomRPg8nwguaSQP289/wN+17TB/DImgcitiNwiJxYXBFQZQ7UGryIBuet HYOETs8sk2NgwbYnzs5jf+58Ao6PTYp5CWiSwemIwiPG9UbPQWopS2776ZuelRf/XU 5WY7xyl4R9iDrD38+SDNMwHbVrffYY888esYy9WU= 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 5.5 22/65] scsi: ufs: Fix ufshcd_hold() caused scheduling while atomic Date: Mon, 20 Apr 2020 14:38:26 +0200 Message-Id: <20200420121511.189790190@linuxfoundation.org> X-Mailer: git-send-email 2.26.1 In-Reply-To: <20200420121505.909671922@linuxfoundation.org> References: <20200420121505.909671922@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 @@ -1542,6 +1542,11 @@ 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);