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 71CAEC2BBC7 for ; Sat, 11 Apr 2020 23:15:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 43BB720757 for ; Sat, 11 Apr 2020 23:15:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586646915; bh=4MNDq5JIfNUOVoGypVOfJ3S7koSKgHGx/rT77mOia/c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=w3ZyIddTo6Zs3wgrPsf+70RMcbkSVPMnD0j1d1ZWc+tdGop/NtF5689g9fPk6KiqF jomm7b0FdCAzlUQn8+2Rmkb6wa/4UtAg131t0adbqvYE4seTtStbS2Dgnu+OLLXy3j Di714Ng65n5W69vgt2nkS7xFLmJ7Q+C/vSRdDWZ8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727520AbgDKXPN (ORCPT ); Sat, 11 Apr 2020 19:15:13 -0400 Received: from mail.kernel.org ([198.145.29.99]:57424 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730965AbgDKXPH (ORCPT ); Sat, 11 Apr 2020 19:15:07 -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 8F42D20757; Sat, 11 Apr 2020 23:15:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586646907; bh=4MNDq5JIfNUOVoGypVOfJ3S7koSKgHGx/rT77mOia/c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EGBqIBLKIjxLCr1uGTkkzOTVguoEbt5ITYqhBETodNHFjFkqClTF51xY1ZIJfxRVN H1vdUvmxx7eAbkMYYykJBb4yBR0Dt62KtGIr94eC9ei0qfgUr2tDeixxLIx2dlbuzo Ka2B+iiZzZObDOnYiSA45k3zozzc47LDzi6VGk/M= 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 4.4 16/16] scsi: ufs: Fix ufshcd_hold() caused scheduling while atomic Date: Sat, 11 Apr 2020 19:14:46 -0400 Message-Id: <20200411231447.27182-16-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200411231447.27182-1-sashal@kernel.org> References: <20200411231447.27182-1-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 19f82069c68ac..bc7f8d634c805 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -595,6 +595,11 @@ 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