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=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 65C51C2BBC7 for ; Sat, 11 Apr 2020 23:13:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2776020CC7 for ; Sat, 11 Apr 2020 23:13:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586646815; bh=tGOQQ9djfq9Q6LbI8RPsPUKkrC6zjvSHm/Qh17ZVSTM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=D4Ko364kVZXhe4vAP0/GWz/o+JIsp2v3ar8UUmX4xilY/1zShMCkJxaL/uCp5+g8f 92zq9rthSy38uOM79ebxLCP4u6hxKA0eqrZrEFIKZ+4OTLHF3Rg5P2mQOueRtRCs3N LiMKU/iuPsbSpY0d0Pwu/KLbnWYD6kreyU9fGo+U= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729198AbgDKXNd (ORCPT ); Sat, 11 Apr 2020 19:13:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:54278 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730370AbgDKXNQ (ORCPT ); Sat, 11 Apr 2020 19:13:16 -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 17741216FD; Sat, 11 Apr 2020 23:13:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586646796; bh=tGOQQ9djfq9Q6LbI8RPsPUKkrC6zjvSHm/Qh17ZVSTM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gk4xj1xI6X0TVfCM+43J8sMsHHDq8PBQgSYn4pCMeO3s4e+Q29lzTALRs0WLTthMC w7XqN/+Vz+qG66Ysqa7HMOYjWy76d96ytME3AuOy9HZQ9F3+JKrfAw5hXLOtmwtxmc dWyOmWx7BSj9wAxoW6u7QjQRK8U4uIFEHdzo1+xQ= 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 4.19 59/66] scsi: ufs: Fix ufshcd_hold() caused scheduling while atomic Date: Sat, 11 Apr 2020 19:11:56 -0400 Message-Id: <20200411231203.25933-59-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200411231203.25933-1-sashal@kernel.org> References: <20200411231203.25933-1-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 b3dee24917a86..d91209ba18c86 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -1563,6 +1563,11 @@ 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