From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752343AbaBZLIH (ORCPT ); Wed, 26 Feb 2014 06:08:07 -0500 Received: from moutng.kundenserver.de ([212.227.126.130]:61981 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751635AbaBZLCn (ORCPT ); Wed, 26 Feb 2014 06:02:43 -0500 From: Arnd Bergmann To: linux-kernel@vger.kernel.org Cc: Arnd Bergmann , Jens Axboe Subject: [PATCH 04/16] swim3: fix interruptible_sleep_on race Date: Wed, 26 Feb 2014 12:01:44 +0100 Message-Id: <1393412516-3762435-5-git-send-email-arnd@arndb.de> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1393412516-3762435-1-git-send-email-arnd@arndb.de> References: <1393412516-3762435-1-git-send-email-arnd@arndb.de> X-Provags-ID: V02:K0:rA7EnyqV2LXWqbvB3EOSY+GIhCPocorjvgfjR0jVIsP 7JBXdr8hVi05sk3ZzYHfzlFONj2JtnfWGVeXMsrkJM4C16yzgF Tj46SqVxNhSSR3FA6HmsjonFz8MG7Lk+CdXIEqruNjYjEHqNmb YegM2Lw9KfAsWxryPp6AOocRgyNchY5JBs7tqw/IJndvSWhVIO XmP5ErLd288+RSoBGOiqz7twPUtUAhM147nJQYBwUXdIwpB/Ba GB0qdhmvs+8uZBs1IIswSwDTaDo8H7izjwaaF+UomFmyjO518W BEiUWw/6e5qYTzPG8soARpnRRSpeqV0Nl0OyyWMTM0ZM4SxTZY Ps8hlzufewZ8h7VwUsxI9DaWzGCDNvvYWWaS9mxVF Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org interruptible_sleep_on is racy and going away. This replaces the one caller in the swim3 driver with the equivalent race-free wait_event_interruptible call. Since we're here already, this also fixes the case where we get interrupted from atomic context, which used to just spin in the loop. Signed-off-by: Arnd Bergmann Cc: Jens Axboe --- drivers/block/swim3.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/drivers/block/swim3.c b/drivers/block/swim3.c index 20e061c..c74f7b5 100644 --- a/drivers/block/swim3.c +++ b/drivers/block/swim3.c @@ -30,6 +30,7 @@ #include #include #include +#include #include #include #include @@ -840,14 +841,17 @@ static int grab_drive(struct floppy_state *fs, enum swim_state state, spin_lock_irqsave(&swim3_lock, flags); if (fs->state != idle && fs->state != available) { ++fs->wanted; - while (fs->state != available) { + /* this will enable irqs in order to sleep */ + if (!interruptible) + wait_event_lock_irq(fs->wait, + fs->state == available, + swim3_lock); + else if (wait_event_interruptible_lock_irq(fs->wait, + fs->state == available, + swim3_lock)) { + --fs->wanted; spin_unlock_irqrestore(&swim3_lock, flags); - if (interruptible && signal_pending(current)) { - --fs->wanted; - return -EINTR; - } - interruptible_sleep_on(&fs->wait); - spin_lock_irqsave(&swim3_lock, flags); + return -EINTR; } --fs->wanted; } -- 1.8.3.2