From: Julian Wiedmann Date: Tue, 20 Mar 2018 06:59:14 +0000 (+0100) Subject: s390/qeth: lock read device while queueing next buffer X-Git-Tag: v4.1.52~346 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7e8e91a00842e122e7e1ab38ab4a0b3b51571f12;p=thirdparty%2Fkernel%2Fstable.git s390/qeth: lock read device while queueing next buffer [ 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: Sasha Levin --- diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c index e5016e79a758f..d9e3ee93fb1e5 100644 --- 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_card *card, unsigned int queue) 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 qeth_card *card) 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; @@ -1173,7 +1183,7 @@ static void qeth_irq(struct ccw_device *cdev, unsigned long intparm, 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;