From patchwork Mon Mar 8 21:10:56 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rafael Wysocki X-Patchwork-Id: 84146 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter.kernel.org (8.14.3/8.14.3) with ESMTP id o28L8NPR029952 for ; Mon, 8 Mar 2010 21:08:24 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755523Ab0CHVIW (ORCPT ); Mon, 8 Mar 2010 16:08:22 -0500 Received: from ogre.sisk.pl ([217.79.144.158]:37388 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755410Ab0CHVIV (ORCPT ); Mon, 8 Mar 2010 16:08:21 -0500 Received: from localhost (localhost.localdomain [127.0.0.1]) by ogre.sisk.pl (Postfix) with ESMTP id 6FBA3152222; Mon, 8 Mar 2010 21:42:37 +0100 (CET) Received: from ogre.sisk.pl ([127.0.0.1]) by localhost (ogre.sisk.pl [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 32065-10; Mon, 8 Mar 2010 21:42:30 +0100 (CET) Received: from tosh.localnet (220-bem-13.acn.waw.pl [82.210.184.220]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ogre.sisk.pl (Postfix) with ESMTP id 5438411A11F; Mon, 8 Mar 2010 21:42:30 +0100 (CET) From: "Rafael J. Wysocki" To: Len Brown Subject: Re: [Resend][PATCH] ACPI / EC: Remove race between EC driver and suspend process (rev. 3) Date: Mon, 8 Mar 2010 22:10:56 +0100 User-Agent: KMail/1.12.4 (Linux/2.6.33-git-rjw; KDE/4.3.5; x86_64; ; ) Cc: Alexey Starikovskiy , ACPI Devel Maling List , pm list , LKML , Maxim Levitsky References: <201002272140.36891.rjw@sisk.pl> <201003040152.58437.rjw@sisk.pl> In-Reply-To: <201003040152.58437.rjw@sisk.pl> MIME-Version: 1.0 Message-Id: <201003082210.56660.rjw@sisk.pl> X-Virus-Scanned: amavisd-new at ogre.sisk.pl using MkS_Vir for Linux Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter.kernel.org [140.211.167.41]); Mon, 08 Mar 2010 21:08:24 +0000 (UTC) Index: linux-2.6/drivers/acpi/ec.c =================================================================== --- linux-2.6.orig/drivers/acpi/ec.c +++ linux-2.6/drivers/acpi/ec.c @@ -76,8 +76,9 @@ enum ec_command { enum { EC_FLAGS_QUERY_PENDING, /* Query is pending */ EC_FLAGS_GPE_STORM, /* GPE storm detected */ - EC_FLAGS_HANDLERS_INSTALLED /* Handlers for GPE and + EC_FLAGS_HANDLERS_INSTALLED, /* Handlers for GPE and * OpReg are installed */ + EC_FLAGS_BLOCKED, /* Transactions are blocked */ }; /* If we find an EC via the ECDT, we need to keep a ptr to its context */ @@ -291,6 +292,10 @@ static int acpi_ec_transaction(struct ac if (t->rdata) memset(t->rdata, 0, t->rlen); mutex_lock(&ec->lock); + if (test_bit(EC_FLAGS_BLOCKED, &ec->flags)) { + status = -EINVAL; + goto unlock; + } if (ec->global_lock) { status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); if (ACPI_FAILURE(status)) { @@ -453,6 +458,32 @@ int ec_transaction(u8 command, EXPORT_SYMBOL(ec_transaction); +void acpi_ec_block_transactions(void) +{ + struct acpi_ec *ec = first_ec; + + if (!ec) + return; + + mutex_lock(&ec->lock); + /* Prevent transactions from being carried out */ + set_bit(EC_FLAGS_BLOCKED, &ec->flags); + mutex_unlock(&ec->lock); +} + +void acpi_ec_unblock_transactions(void) +{ + struct acpi_ec *ec = first_ec; + + if (!ec) + return; + + mutex_lock(&ec->lock); + /* Allow transactions to be carried out again */ + clear_bit(EC_FLAGS_BLOCKED, &ec->flags); + mutex_unlock(&ec->lock); +} + static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data) { int result; Index: linux-2.6/drivers/acpi/internal.h =================================================================== --- linux-2.6.orig/drivers/acpi/internal.h +++ linux-2.6/drivers/acpi/internal.h @@ -49,6 +49,8 @@ void acpi_early_processor_set_pdc(void); int acpi_ec_init(void); int acpi_ec_ecdt_probe(void); int acpi_boot_ec_enable(void); +void acpi_ec_block_transactions(void); +void acpi_ec_unblock_transactions(void); /*-------------------------------------------------------------------------- Suspend/Resume Index: linux-2.6/drivers/acpi/sleep.c =================================================================== --- linux-2.6.orig/drivers/acpi/sleep.c +++ linux-2.6/drivers/acpi/sleep.c @@ -552,8 +552,17 @@ static void acpi_hibernation_leave(void) hibernate_nvs_restore(); } -static void acpi_pm_enable_gpes(void) +static int acpi_pm_pre_restore(void) { + acpi_disable_all_gpes(); + acpi_os_wait_events_complete(NULL); + acpi_ec_block_transactions(); + return 0; +} + +static void acpi_pm_restore_cleanup(void) +{ + acpi_ec_unblock_transactions(); acpi_enable_all_runtime_gpes(); } @@ -565,8 +574,8 @@ static struct platform_hibernation_ops a .prepare = acpi_pm_prepare, .enter = acpi_hibernation_enter, .leave = acpi_hibernation_leave, - .pre_restore = acpi_pm_disable_gpes, - .restore_cleanup = acpi_pm_enable_gpes, + .pre_restore = acpi_pm_pre_restore, + .restore_cleanup = acpi_pm_restore_cleanup, }; /** @@ -618,8 +627,8 @@ static struct platform_hibernation_ops a .prepare = acpi_pm_disable_gpes, .enter = acpi_hibernation_enter, .leave = acpi_hibernation_leave, - .pre_restore = acpi_pm_disable_gpes, - .restore_cleanup = acpi_pm_enable_gpes, + .pre_restore = acpi_pm_pre_restore, + .restore_cleanup = acpi_pm_restore_cleanup, .recover = acpi_pm_finish, }; #endif /* CONFIG_HIBERNATION */