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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 02EB7E95A91 for ; Mon, 9 Oct 2023 13:52:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377527AbjJINwf (ORCPT ); Mon, 9 Oct 2023 09:52:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48420 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1377497AbjJINwc (ORCPT ); Mon, 9 Oct 2023 09:52:32 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2E14CA3 for ; Mon, 9 Oct 2023 06:52:31 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6C1A9C433C9; Mon, 9 Oct 2023 13:52:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1696859550; bh=gObAoJ4Dn/5I+oUodCfedwjaxTsYp/tQNumyVH/g/fE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cHitsHtyMtWGSmCCqYbQp+vMlIAKIh7MHOGvoI7a+BBLtLIy9nZfX/b2JLltut/68 4y7uEGZPGi6aLTEIVOdjKZYeltcVhrBnV1NhbacFMJFm17eNh3NhiWKDTpRnZblUZU utFZBQ31TI7+wQAqb3+Ds2RrVWOtNy6S0di1K55c= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Damien Le Moal , Hannes Reinecke , "Chia-Lin Kao (AceLan)" , Niklas Cassel , Geert Uytterhoeven , "Martin K. Petersen" , Bart Van Assche Subject: [PATCH 4.19 56/91] ata: libata-core: Fix ata_port_request_pm() locking Date: Mon, 9 Oct 2023 15:06:28 +0200 Message-ID: <20231009130113.460651109@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231009130111.518916887@linuxfoundation.org> References: <20231009130111.518916887@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Damien Le Moal commit 3b8e0af4a7a331d1510e963b8fd77e2fca0a77f1 upstream. The function ata_port_request_pm() checks the port flag ATA_PFLAG_PM_PENDING and calls ata_port_wait_eh() if this flag is set to ensure that power management operations for a port are not scheduled simultaneously. However, this flag check is done without holding the port lock. Fix this by taking the port lock on entry to the function and checking the flag under this lock. The lock is released and re-taken if ata_port_wait_eh() needs to be called. The two WARN_ON() macros checking that the ATA_PFLAG_PM_PENDING flag was cleared are removed as the first call is racy and the second one done without holding the port lock. Fixes: 5ef41082912b ("ata: add ata port system PM callbacks") Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal Reviewed-by: Hannes Reinecke Tested-by: Chia-Lin Kao (AceLan) Reviewed-by: Niklas Cassel Tested-by: Geert Uytterhoeven Reviewed-by: Martin K. Petersen Reviewed-by: Bart Van Assche Signed-off-by: Greg Kroah-Hartman --- drivers/ata/libata-core.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -5756,17 +5756,19 @@ static void ata_port_request_pm(struct a struct ata_link *link; unsigned long flags; - /* Previous resume operation might still be in - * progress. Wait for PM_PENDING to clear. + spin_lock_irqsave(ap->lock, flags); + + /* + * A previous PM operation might still be in progress. Wait for + * ATA_PFLAG_PM_PENDING to clear. */ if (ap->pflags & ATA_PFLAG_PM_PENDING) { + spin_unlock_irqrestore(ap->lock, flags); ata_port_wait_eh(ap); - WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING); + spin_lock_irqsave(ap->lock, flags); } - /* request PM ops to EH */ - spin_lock_irqsave(ap->lock, flags); - + /* Request PM operation to EH */ ap->pm_mesg = mesg; ap->pflags |= ATA_PFLAG_PM_PENDING; ata_for_each_link(link, ap, HOST_FIRST) { @@ -5778,10 +5780,8 @@ static void ata_port_request_pm(struct a spin_unlock_irqrestore(ap->lock, flags); - if (!async) { + if (!async) ata_port_wait_eh(ap); - WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING); - } } /*