From patchwork Wed Apr 22 09:57:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 227100 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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, 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 76063C55186 for ; Wed, 22 Apr 2020 10:50:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 447632073A for ; Wed, 22 Apr 2020 10:50:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587552617; bh=+SrwVG1wkcsfrVwkbz4KAAKDbgLeN74p2Cc+qM20LlY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=uUGfjwtrZKfmzbyAqBRShj/FJrxGxV8I6h0BZMr15Y7cfBTSLmLS3WWcBeW4z/nKl Ngfo8FI9hGQLQa6dAkD4qDgI3Q8KynMqqb3VcqswAlUiGkO8jNogBO2Zh+zcxmJHU9 WEfbfri/ZShiNKcXjMV/TMxKXOUvO12A7qM4xJYA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729012AbgDVKMf (ORCPT ); Wed, 22 Apr 2020 06:12:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:45692 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728769AbgDVKMe (ORCPT ); Wed, 22 Apr 2020 06:12:34 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 98EC920575; Wed, 22 Apr 2020 10:12:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587550354; bh=+SrwVG1wkcsfrVwkbz4KAAKDbgLeN74p2Cc+qM20LlY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Z7ujgR5POl3x7EgGWVGDs12FjtwdWUi+WDGYivKJ36FNspu4sfgO7msb5+cGQdg0O I/dMw+i/8LZAVX2ofCsONkuzpEsD8FHcREy0xb59UAzDikWT2fnfAfa0iKyLboduI+ s7JBVINHM4EUtoRxlZIrjnZk8hiKTW20T6+BO/LA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hongwu Su , Asutosh Das , Bean Huo , Stanley Chu , Can Guo , "Martin K. Petersen" Subject: [PATCH 4.14 113/199] scsi: ufs: Fix ufshcd_hold() caused scheduling while atomic Date: Wed, 22 Apr 2020 11:57:19 +0200 Message-Id: <20200422095108.968120627@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200422095057.806111593@linuxfoundation.org> References: <20200422095057.806111593@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Can Guo commit c63d6099a7959ecc919b2549dc6b71f53521f819 upstream. 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: Greg Kroah-Hartman --- drivers/scsi/ufs/ufshcd.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -1448,6 +1448,11 @@ start: */ 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);