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 3DE14CA9EBD for ; Sat, 26 Oct 2019 13:29:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 141D0206DD for ; Sat, 26 Oct 2019 13:29:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572096552; bh=0gMrf58nyOQicRuJIsnB9fgJMehx9YiSuKXoMEcGI28=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=eKqQ01AbHWuAl5sAp5aHyHD/DqDD/8WkDf0ILU98+XlLKlFNPbTte016TcAcjRejo nB+Us0mVzx5qHTU8mTKcj3lHPeFtR56jjqMFfcxhUBM17eM9Zr9SHhIqqCBREmdUUI Q1q2L90fWx9EACtVdtlPsbIHQtwMSKUNAw0/oT3I= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729272AbfJZN3K (ORCPT ); Sat, 26 Oct 2019 09:29:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:42316 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727127AbfJZNUe (ORCPT ); Sat, 26 Oct 2019 09:20:34 -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 B3717222BD; Sat, 26 Oct 2019 13:20:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572096033; bh=0gMrf58nyOQicRuJIsnB9fgJMehx9YiSuKXoMEcGI28=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XvT2yo23keVe2VXfZamfI/l28P5t+AkUnBS+mUn4TKR05cpORLtWlk7y4SqRt0GlP 6EM5NC6jZLzY5wNCm/0msNPhnBGpAvyOb1DbG1C+bmzeDslCbWZ+GoWMfZrxyJqkhi IKvN6YNW9I5A+kCK/p0fr0L0VaNIiH3/jOdPWSHo= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Keith Busch , Edmund Nadolski , Christoph Hellwig , Sasha Levin , linux-nvme@lists.infradead.org Subject: [PATCH AUTOSEL 4.19 43/59] nvme: Prevent resets during paused controller state Date: Sat, 26 Oct 2019 09:18:54 -0400 Message-Id: <20191026131910.3435-43-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191026131910.3435-1-sashal@kernel.org> References: <20191026131910.3435-1-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: Keith Busch [ Upstream commit 4c75f877853cfa81b12374a07208e07b077f39b8 ] A paused controller is doing critical internal activation work in the background. Prevent subsequent controller resets from occurring during this period by setting the controller state to RESETTING first. A helper function, nvme_try_sched_reset_work(), is introduced for these paths so they may continue with scheduling the reset_work after they've completed their uninterruptible critical section. Tested-by: Edmund Nadolski Reviewed-by: Christoph Hellwig Signed-off-by: Keith Busch Signed-off-by: Sasha Levin --- drivers/nvme/host/core.c | 29 +++++++++++++++++++++++++---- 1 file changed, 25 insertions(+), 4 deletions(-) diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index ddd5c72a565ad..95d4f1a6dd795 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -126,6 +126,21 @@ static void nvme_queue_scan(struct nvme_ctrl *ctrl) queue_work(nvme_wq, &ctrl->scan_work); } +/* + * Use this function to proceed with scheduling reset_work for a controller + * that had previously been set to the resetting state. This is intended for + * code paths that can't be interrupted by other reset attempts. A hot removal + * may prevent this from succeeding. + */ +static int nvme_try_sched_reset(struct nvme_ctrl *ctrl) +{ + if (ctrl->state != NVME_CTRL_RESETTING) + return -EBUSY; + if (!queue_work(nvme_reset_wq, &ctrl->reset_work)) + return -EBUSY; + return 0; +} + int nvme_reset_ctrl(struct nvme_ctrl *ctrl) { if (!nvme_change_ctrl_state(ctrl, NVME_CTRL_RESETTING)) @@ -3445,13 +3460,13 @@ static void nvme_fw_act_work(struct work_struct *work) if (time_after(jiffies, fw_act_timeout)) { dev_warn(ctrl->device, "Fw activation timeout, reset controller\n"); - nvme_reset_ctrl(ctrl); - break; + nvme_try_sched_reset(ctrl); + return; } msleep(100); } - if (ctrl->state != NVME_CTRL_LIVE) + if (!nvme_change_ctrl_state(ctrl, NVME_CTRL_LIVE)) return; nvme_start_queues(ctrl); @@ -3467,7 +3482,13 @@ static void nvme_handle_aen_notice(struct nvme_ctrl *ctrl, u32 result) nvme_queue_scan(ctrl); break; case NVME_AER_NOTICE_FW_ACT_STARTING: - queue_work(nvme_wq, &ctrl->fw_act_work); + /* + * We are (ab)using the RESETTING state to prevent subsequent + * recovery actions from interfering with the controller's + * firmware activation. + */ + if (nvme_change_ctrl_state(ctrl, NVME_CTRL_RESETTING)) + queue_work(nvme_wq, &ctrl->fw_act_work); break; #ifdef CONFIG_NVME_MULTIPATH case NVME_AER_NOTICE_ANA: -- 2.20.1