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,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 54220C2BBC7 for ; Sat, 11 Apr 2020 23:43:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2458F20709 for ; Sat, 11 Apr 2020 23:43:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586648581; bh=0go0yJt6cQE8yciLIioduH6bZbOdpupXHF1LgaHvoGc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=CAnkSqaqpNqWPIu8GuKtb4oOwoTt5ZI8d6e6EwTy+ERHKJK/L4ggvHx+dMy+ZHmK7 uuPONSGbRlGqH1RXYBW/OVcke+wVuhexwSdV3ieOfJbNMkIi4lOvgW5Tk3C2WOMBjG WFmqYwD+YkW6YdCDAZhXUmJhnav0FypD4oh0xTVY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728838AbgDKXmw (ORCPT ); Sat, 11 Apr 2020 19:42:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:41908 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728433AbgDKXG3 (ORCPT ); Sat, 11 Apr 2020 19:06:29 -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 D63A520708; Sat, 11 Apr 2020 23:06:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586646390; bh=0go0yJt6cQE8yciLIioduH6bZbOdpupXHF1LgaHvoGc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=U7x79t9DRX3kEv51Q48FK83g4y9M6GB7xqZpW763n0PkPaEC0zpgAZeRigxhMVQjo OtoKVM7e2SHI4fzgYgTyfj14bB3u0fhVHKLC+JSflnhwtVSJcEi/MGWOQN98zgVjn4 TUHorDm34RH057+EG9QoMjk/XPZ9GBf3e6+FPnBg= 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 5.6 129/149] scsi: ufs: Fix ufshcd_hold() caused scheduling while atomic Date: Sat, 11 Apr 2020 19:03:26 -0400 Message-Id: <20200411230347.22371-129-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200411230347.22371-1-sashal@kernel.org> References: <20200411230347.22371-1-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 2d705694636c2..682f85f800d0f 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -1518,6 +1518,11 @@ 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