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 08C07C3815B for ; Mon, 20 Apr 2020 12:46:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D9BC92078E for ; Mon, 20 Apr 2020 12:46:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587386779; bh=btLCEYeBJIjkGx7H1pLmIotBGINHe2RGtI6EmF3ycNs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=z5Dok/vpEoTdFOS1CWwwSePOBnwaqC3oVjqBqIFmQXqWKnlbn0IbSY7Kk8ThYAUk8 iSjgsBgi+aNjrAhjzmPFzIbQ+qlRXyyt1sL/FQwTEKIpyRE9+Umf5vW10umXZtaW1p FTDQAK9BCJEXl4edJKJHvdpvWerLnvos9rhMu/Ns= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728174AbgDTMqS (ORCPT ); Mon, 20 Apr 2020 08:46:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:41414 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728162AbgDTMqL (ORCPT ); Mon, 20 Apr 2020 08:46:11 -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 E4A532072B; Mon, 20 Apr 2020 12:46:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587386770; bh=btLCEYeBJIjkGx7H1pLmIotBGINHe2RGtI6EmF3ycNs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=102BixgXutHMaXK4kBYrTJEZLWBleosgNq/J9p3eXgAUwenP5/OqV7Oiao1sJ9gr8 0LePxNhVP1u1B5U5JzaHnzDW7bYAekkvQZh+OLV5TBu4KL4Uit61EgokkuZn0kZN9O nX5iyfm49yw11E28B0aGRoAniz6HavaZKjcpl+c4= 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 5.4 20/60] scsi: ufs: Fix ufshcd_hold() caused scheduling while atomic Date: Mon, 20 Apr 2020 14:38:58 +0200 Message-Id: <20200420121507.378831600@linuxfoundation.org> X-Mailer: git-send-email 2.26.1 In-Reply-To: <20200420121500.490651540@linuxfoundation.org> References: <20200420121500.490651540@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 @@ -1539,6 +1539,11 @@ 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);