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 A0BD6C2BBC7 for ; Sat, 11 Apr 2020 23:16:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6F26021655 for ; Sat, 11 Apr 2020 23:16:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586646992; bh=ywdHHF/v2TaGRn3tam7MmQpVBcv4oTWikAk47HfYV/Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=KGbfx6zXa8KDFVcmky7+3Q62RLy6519PR5Z9OtWXxVlxWzvL5AGFNdtSMenpS3YE1 pSYfx2i8VDfVKGkuujLrlpSznHWxuVEuPptAoSpXWjlZeJZSpRkjd4eR3i8UUGa1qr 73cpWy7mN+BYhvc2IA0croUxDY8h7/UDV4JZIUJ0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730854AbgDKXOo (ORCPT ); Sat, 11 Apr 2020 19:14:44 -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: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@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