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 EACF3C2BA19 for ; Sat, 11 Apr 2020 23:18:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B95DF20757 for ; Sat, 11 Apr 2020 23:18:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586647115; bh=hFHx6RqkUyo6iXHb3PvAoIlELuZY+iXvlUN9yOBwKZU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=FXZGneV5weVTdbpav3MAjh7xEjv37+/9C13feRpuovLq4pa7GlfT2hHcz+3S4AC2F 16nWL+2z9qPYGRHeqEALhkheU+jnuc1Ii3/6m1isoEu0coUyFI3pG6AsHEgLqIFpp3 2Gp2DBZKriGSa2nnBXqQO8sc2ALtBREGV3hdDy8I= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730802AbgDKXSe (ORCPT ); Sat, 11 Apr 2020 19:18:34 -0400 Received: from mail.kernel.org ([198.145.29.99]:55720 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730671AbgDKXOI (ORCPT ); Sat, 11 Apr 2020 19:14:08 -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 3A17621744; Sat, 11 Apr 2020 23:14:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586646848; bh=hFHx6RqkUyo6iXHb3PvAoIlELuZY+iXvlUN9yOBwKZU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SpJ5EB6SyS68xvPahWfcs3BKDNC4v5pp9RsH+2ihakzMsq0RjdnrO/Fky8yUQDLBH vnfdbRm25BW9+eLSWvNi1rVeHD/keJm5l2hcDPO2GEEfLhwtxxGPoXTKDBNbLstBHl iuA1TODlpbgLmYADse4OzkcjKnMajpz02KUhuWck= 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 4.14 34/37] scsi: ufs: Fix ufshcd_hold() caused scheduling while atomic Date: Sat, 11 Apr 2020 19:13:23 -0400 Message-Id: <20200411231327.26550-34-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200411231327.26550-1-sashal@kernel.org> References: <20200411231327.26550-1-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 c350453246952..6dbdddffa0b31 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -1448,6 +1448,11 @@ 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