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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 B3D26C2BA19 for ; Sat, 11 Apr 2020 23:14:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 82C122166E for ; Sat, 11 Apr 2020 23:14:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586646889; bh=ywdHHF/v2TaGRn3tam7MmQpVBcv4oTWikAk47HfYV/Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=kQhRWflb6kLnP4dC46Ppcg+GAERiVii0jnyvQJrnRV4HhFQYH8V0TX8l5uVcnaplL 5qs0Go4Z5zZ11sWQMg1nYCWnY3+OF5P2PMhaITlTE0E89Bx5r4lSk7biNzUZuChcEB MyKWXBsLzZts/o7giqLK+7xjYMhzsvjo6LfiWO2g= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730452AbgDKXOr (ORCPT ); Sat, 11 Apr 2020 19:14:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:56702 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730807AbgDKXOn (ORCPT ); Sat, 11 Apr 2020 19:14:43 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 455D820708; Sat, 11 Apr 2020 23:14:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586646883; bh=ywdHHF/v2TaGRn3tam7MmQpVBcv4oTWikAk47HfYV/Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VzyWtJKL+MCb0e0EHdQZfkmf6LVLwOpgToCBr35ehK5LUN42P7DnCcRmZedxCiV7Y xLbOlPvgTzkje46mAHI1ss8dNqCrmTsUirp05+JJRLfpUrE/wtwf0Jq6h30znzNe/o m+5avuiv3lon7tVAB+luO5nNstCJQ6Q80gGn0Wl0= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Can Guo , Hongwu Su , Asutosh Das , Bean Huo , Stanley Chu , "Martin K . Petersen" , Sasha Levin , linux-scsi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org Subject: [PATCH AUTOSEL 4.9 24/26] scsi: ufs: Fix ufshcd_hold() caused scheduling while atomic Date: Sat, 11 Apr 2020 19:14:11 -0400 Message-Id: <20200411231413.26911-24-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200411231413.26911-1-sashal@kernel.org> References: <20200411231413.26911-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore 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 [ Upstream commit c63d6099a7959ecc919b2549dc6b71f53521f819 ] 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: Sasha Levin --- 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 394df57894e6b..9bd26efcc1a10 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -682,6 +682,11 @@ 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); -- 2.20.1