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 879D7C55186 for ; Wed, 22 Apr 2020 10:01:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 59D8F20774 for ; Wed, 22 Apr 2020 10:01:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587549677; bh=npYd3lh51a/ehBF6fTGdVyIDmLK+MDuSxQxua5ODT80=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ETUqiKzPJ3zod8han2zuJFVAwTjVnvBdEO1BVAKhk+G59x1CndtEqs/6C18eowfkw phVtxxo2DOr4nvs2Vn3M1JnzMCaqbKLAw7UU7pX9NeMj4wZpVkAb+1LX00hrL+hRJH 72FlVuPaIsXvGOz6OfgoHVk6w/dhMZYYYGrf6O8k= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726788AbgDVKBQ (ORCPT ); Wed, 22 Apr 2020 06:01:16 -0400 Received: from mail.kernel.org ([198.145.29.99]:49492 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726442AbgDVKBP (ORCPT ); Wed, 22 Apr 2020 06:01:15 -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 398A420774; Wed, 22 Apr 2020 10:01:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587549674; bh=npYd3lh51a/ehBF6fTGdVyIDmLK+MDuSxQxua5ODT80=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IVUBhktRrurSNJrUKhm0Zzc788l4Kf+fMDpiV9BHlLOBEuItb/Zji38vAEOLtl/St 4fh/yfpy1f2yNgVhxzycPRxFmgrp84sr1EMcp6iC3GjA8lJDjJN6SxZ1zgancW8Jd3 OUqiQ0wqmV3yZuhdF/PqBPbF5368liltIOJNIRw8= 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 4.4 058/100] scsi: ufs: Fix ufshcd_hold() caused scheduling while atomic Date: Wed, 22 Apr 2020 11:56:28 +0200 Message-Id: <20200422095033.529908903@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200422095022.476101261@linuxfoundation.org> References: <20200422095022.476101261@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 @@ -595,6 +595,11 @@ 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);