From patchwork Wed Jun 3 07:48:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kai-Heng Feng X-Patchwork-Id: 1302829 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-ide-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=canonical.com Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 49cLd33wMZz9sTD for ; Wed, 3 Jun 2020 17:48:39 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725866AbgFCHse (ORCPT ); Wed, 3 Jun 2020 03:48:34 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:40416 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725275AbgFCHsd (ORCPT ); Wed, 3 Jun 2020 03:48:33 -0400 Received: from 61-220-137-37.hinet-ip.hinet.net ([61.220.137.37] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1jgO8S-0008I8-SH; Wed, 03 Jun 2020 07:48:29 +0000 From: Kai-Heng Feng To: axboe@kernel.dk Cc: Kai-Heng Feng , John Garry , linux-ide@vger.kernel.org (open list:LIBATA SUBSYSTEM (Serial and Parallel ATA drivers)), linux-kernel@vger.kernel.org (open list) Subject: [PATCH v3] libata: Use per port sync for detach Date: Wed, 3 Jun 2020 15:48:19 +0800 Message-Id: <20200603074819.21639-1-kai.heng.feng@canonical.com> X-Mailer: git-send-email 2.17.1 Sender: linux-ide-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ide@vger.kernel.org Commit 130f4caf145c ("libata: Ensure ata_port probe has completed before detach") may cause system freeze during suspend. Using async_synchronize_full() in PM callbacks is wrong, since async callbacks that are already scheduled may wait for not-yet-scheduled callbacks, causes a circular dependency. Instead of using big hammer like async_synchronize_full(), use async cookie to make sure port probe are synced, without affecting other scheduled PM callbacks. Fixes: 130f4caf145c ("libata: Ensure ata_port probe has completed before detach") BugLink: https://bugs.launchpad.net/bugs/1867983 Suggested-by: John Garry Signed-off-by: Kai-Heng Feng Tested-by: John Garry --- v3: - Move the comment to properly align with the code. v2: - Sync up to cookie + 1. - Squash the synchronization into the same loop. drivers/ata/libata-core.c | 11 +++++------ include/linux/libata.h | 3 +++ 2 files changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index 69361ec43db5..b1cd4d97bc2a 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -42,7 +42,6 @@ #include #include #include -#include #include #include #include @@ -5778,7 +5777,7 @@ int ata_host_register(struct ata_host *host, struct scsi_host_template *sht) /* perform each probe asynchronously */ for (i = 0; i < host->n_ports; i++) { struct ata_port *ap = host->ports[i]; - async_schedule(async_port_probe, ap); + ap->cookie = async_schedule(async_port_probe, ap); } return 0; @@ -5920,11 +5919,11 @@ void ata_host_detach(struct ata_host *host) { int i; - /* Ensure ata_port probe has completed */ - async_synchronize_full(); - - for (i = 0; i < host->n_ports; i++) + for (i = 0; i < host->n_ports; i++) { + /* Ensure ata_port probe has completed */ + async_synchronize_cookie(host->ports[i]->cookie + 1); ata_port_detach(host->ports[i]); + } /* the host is dead now, dissociate ACPI */ ata_acpi_dissociate(host); diff --git a/include/linux/libata.h b/include/linux/libata.h index af832852e620..8a4843704d28 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -22,6 +22,7 @@ #include #include #include +#include /* * Define if arch has non-standard setup. This is a _PCI_ standard @@ -872,6 +873,8 @@ struct ata_port { struct timer_list fastdrain_timer; unsigned long fastdrain_cnt; + async_cookie_t cookie; + int em_message_type; void *private_data;