w1: hold bus_mutex in netlink and search
The bus_mutex needs to be taken to serialize access to a specific bus.
netlink wasn't updated when bus_mutex was added and was calling
without that lock held, and not all of the masters were holding the
bus_mutex in a search. This was causing the ds2490 hardware to stop
responding when both netlink and /sys slaves were executing bus
commands at the same time.
Signed-off-by: David Fries <David@Fries.net>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/w1/masters/ds2490.c b/drivers/w1/masters/ds2490.c
index db0bf32..7404ad30 100644
--- a/drivers/w1/masters/ds2490.c
+++ b/drivers/w1/masters/ds2490.c
@@ -727,9 +727,11 @@
*/
u64 buf[2*64/8];
+ mutex_lock(&master->bus_mutex);
+
/* address to start searching at */
if (ds_send_data(dev, (u8 *)&master->search_id, 8) < 0)
- return;
+ goto search_out;
master->search_id = 0;
value = COMM_SEARCH_ACCESS | COMM_IM | COMM_RST | COMM_SM | COMM_F |
@@ -739,7 +741,7 @@
search_limit = 0;
index = search_type | (search_limit << 8);
if (ds_send_control(dev, value, index) < 0)
- return;
+ goto search_out;
do {
schedule_timeout(jtime);
@@ -791,6 +793,8 @@
master->max_slave_count);
set_bit(W1_WARN_MAX_COUNT, &master->flags);
}
+search_out:
+ mutex_unlock(&master->bus_mutex);
}
#if 0