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authorDavid S. Miller <davem@davemloft.net>2015-10-20 06:08:27 -0700
committerDavid S. Miller <davem@davemloft.net>2015-10-20 06:08:27 -0700
commit26440c835f8b1a491e2704118ac55bf87334366c (patch)
tree3c2d23b59fd49b252fdbf6c09efc41b354933fc6 /drivers/tty/tty_buffer.c
parent371f1c7e0d854796adc622cc3bacfcc5fc638db1 (diff)
parent1099f86044111e9a7807f09523e42d4c9d0fb781 (diff)
downloadop-kernel-dev-26440c835f8b1a491e2704118ac55bf87334366c.zip
op-kernel-dev-26440c835f8b1a491e2704118ac55bf87334366c.tar.gz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts: drivers/net/usb/asix_common.c net/ipv4/inet_connection_sock.c net/switchdev/switchdev.c In the inet_connection_sock.c case the request socket hashing scheme is completely different in net-next. The other two conflicts were overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/tty/tty_buffer.c')
-rw-r--r--drivers/tty/tty_buffer.c22
1 files changed, 17 insertions, 5 deletions
diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c
index 5a3fa89..a660ab1 100644
--- a/drivers/tty/tty_buffer.c
+++ b/drivers/tty/tty_buffer.c
@@ -242,7 +242,10 @@ void tty_buffer_flush(struct tty_struct *tty, struct tty_ldisc *ld)
atomic_inc(&buf->priority);
mutex_lock(&buf->lock);
- while ((next = buf->head->next) != NULL) {
+ /* paired w/ release in __tty_buffer_request_room; ensures there are
+ * no pending memory accesses to the freed buffer
+ */
+ while ((next = smp_load_acquire(&buf->head->next)) != NULL) {
tty_buffer_free(port, buf->head);
buf->head = next;
}
@@ -290,7 +293,10 @@ static int __tty_buffer_request_room(struct tty_port *port, size_t size,
if (n != NULL) {
n->flags = flags;
buf->tail = n;
- b->commit = b->used;
+ /* paired w/ acquire in flush_to_ldisc(); ensures
+ * flush_to_ldisc() sees buffer data.
+ */
+ smp_store_release(&b->commit, b->used);
/* paired w/ acquire in flush_to_ldisc(); ensures the
* latest commit value can be read before the head is
* advanced to the next buffer
@@ -393,7 +399,10 @@ void tty_schedule_flip(struct tty_port *port)
{
struct tty_bufhead *buf = &port->buf;
- buf->tail->commit = buf->tail->used;
+ /* paired w/ acquire in flush_to_ldisc(); ensures
+ * flush_to_ldisc() sees buffer data.
+ */
+ smp_store_release(&buf->tail->commit, buf->tail->used);
schedule_work(&buf->work);
}
EXPORT_SYMBOL(tty_schedule_flip);
@@ -467,7 +476,7 @@ static void flush_to_ldisc(struct work_struct *work)
struct tty_struct *tty;
struct tty_ldisc *disc;
- tty = port->itty;
+ tty = READ_ONCE(port->itty);
if (tty == NULL)
return;
@@ -491,7 +500,10 @@ static void flush_to_ldisc(struct work_struct *work)
* is advancing to the next buffer
*/
next = smp_load_acquire(&head->next);
- count = head->commit - head->read;
+ /* paired w/ release in __tty_buffer_request_room() or in
+ * tty_buffer_flush(); ensures we see the committed buffer data
+ */
+ count = smp_load_acquire(&head->commit) - head->read;
if (!count) {
if (next == NULL) {
check_other_closed(tty);
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