From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Julian Wiedmann , "David S. Miller" Subject: [PATCH 3.18 34/93] s390/qeth: lock read device while queueing next buffer Date: Fri, 6 Apr 2018 15:23:03 +0200 Message-Id: <20180406084226.422048110@linuxfoundation.org> In-Reply-To: <20180406084224.918716300@linuxfoundation.org> References: <20180406084224.918716300@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Julian Wiedmann [ Upstream commit 17bf8c9b3d499d5168537c98b61eb7a1fcbca6c2 ] For calling ccw_device_start(), issue_next_read() needs to hold the device's ccwlock. This is satisfied for the IRQ handler path (where qeth_irq() gets called under the ccwlock), but we need explicit locking for the initial call by the MPC initialization. Signed-off-by: Julian Wiedmann Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/s390/net/qeth_core_main.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) --- a/drivers/s390/net/qeth_core_main.c +++ b/drivers/s390/net/qeth_core_main.c @@ -517,8 +517,7 @@ static inline int qeth_is_cq(struct qeth queue == card->qdio.no_in_queues - 1; } - -static int qeth_issue_next_read(struct qeth_card *card) +static int __qeth_issue_next_read(struct qeth_card *card) { int rc; struct qeth_cmd_buffer *iob; @@ -549,6 +548,17 @@ static int qeth_issue_next_read(struct q return rc; } +static int qeth_issue_next_read(struct qeth_card *card) +{ + int ret; + + spin_lock_irq(get_ccwdev_lock(CARD_RDEV(card))); + ret = __qeth_issue_next_read(card); + spin_unlock_irq(get_ccwdev_lock(CARD_RDEV(card))); + + return ret; +} + static struct qeth_reply *qeth_alloc_reply(struct qeth_card *card) { struct qeth_reply *reply; @@ -1166,7 +1176,7 @@ static void qeth_irq(struct ccw_device * return; if (channel == &card->read && channel->state == CH_STATE_UP) - qeth_issue_next_read(card); + __qeth_issue_next_read(card); iob = channel->iob; index = channel->buf_no;