[PATCH net 2/5] net/ncsi: Stop monitor if channel times out or is inactive

From: Samuel Mendoza-Jonas
Date: Wed Oct 18 2017 - 22:43:44 EST


ncsi_channel_monitor() misses stopping the channel monitor in several
places that it should, causing a WARN_ON_ONCE() to trigger when the
monitor is re-started later, eg:

[ 459.040000] WARNING: CPU: 0 PID: 1093 at net/ncsi/ncsi-manage.c:269 ncsi_start_channel_monitor+0x7c/0x90
[ 459.040000] CPU: 0 PID: 1093 Comm: kworker/0:3 Not tainted 4.10.17-gaca2fdd #140
[ 459.040000] Hardware name: ASpeed SoC
[ 459.040000] Workqueue: events ncsi_dev_work
[ 459.040000] [<80010094>] (unwind_backtrace) from [<8000d950>] (show_stack+0x20/0x24)
[ 459.040000] [<8000d950>] (show_stack) from [<801dbf70>] (dump_stack+0x20/0x28)
[ 459.040000] [<801dbf70>] (dump_stack) from [<80018d7c>] (__warn+0xe0/0x108)
[ 459.040000] [<80018d7c>] (__warn) from [<80018e70>] (warn_slowpath_null+0x30/0x38)
[ 459.040000] [<80018e70>] (warn_slowpath_null) from [<803f6a08>] (ncsi_start_channel_monitor+0x7c/0x90)
[ 459.040000] [<803f6a08>] (ncsi_start_channel_monitor) from [<803f7664>] (ncsi_configure_channel+0xdc/0x5fc)
[ 459.040000] [<803f7664>] (ncsi_configure_channel) from [<803f8160>] (ncsi_dev_work+0xac/0x474)
[ 459.040000] [<803f8160>] (ncsi_dev_work) from [<8002d244>] (process_one_work+0x1e0/0x450)
[ 459.040000] [<8002d244>] (process_one_work) from [<8002d510>] (worker_thread+0x5c/0x570)
[ 459.040000] [<8002d510>] (worker_thread) from [<80033614>] (kthread+0x124/0x164)
[ 459.040000] [<80033614>] (kthread) from [<8000a5e8>] (ret_from_fork+0x14/0x2c)

This also updates the monitor instead of just returning if
ncsi_xmit_cmd() fails to send the get-link-status command so that the
monitor properly times out.

Fixes: e6f44ed6d04d3 "net/ncsi: Package and channel management"

Signed-off-by: Samuel Mendoza-Jonas <sam@xxxxxxxxxxxxxxxx>
---
net/ncsi/ncsi-manage.c | 15 +++++++++------
1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/net/ncsi/ncsi-manage.c b/net/ncsi/ncsi-manage.c
index b6a449aa9d4b..b022deb39d31 100644
--- a/net/ncsi/ncsi-manage.c
+++ b/net/ncsi/ncsi-manage.c
@@ -202,11 +202,15 @@ static void ncsi_channel_monitor(unsigned long data)
monitor_state = nc->monitor.state;
spin_unlock_irqrestore(&nc->lock, flags);

- if (!enabled || chained)
+ if (!enabled || chained) {
+ ncsi_stop_channel_monitor(nc);
return;
+ }
if (state != NCSI_CHANNEL_INACTIVE &&
- state != NCSI_CHANNEL_ACTIVE)
+ state != NCSI_CHANNEL_ACTIVE) {
+ ncsi_stop_channel_monitor(nc);
return;
+ }

switch (monitor_state) {
case NCSI_CHANNEL_MONITOR_START:
@@ -217,12 +221,9 @@ static void ncsi_channel_monitor(unsigned long data)
nca.type = NCSI_PKT_CMD_GLS;
nca.req_flags = 0;
ret = ncsi_xmit_cmd(&nca);
- if (ret) {
+ if (ret)
netdev_err(ndp->ndev.dev, "Error %d sending GLS\n",
ret);
- return;
- }
-
break;
case NCSI_CHANNEL_MONITOR_WAIT ... NCSI_CHANNEL_MONITOR_WAIT_MAX:
break;
@@ -233,6 +234,8 @@ static void ncsi_channel_monitor(unsigned long data)
ndp->flags |= NCSI_DEV_RESHUFFLE;
}

+ ncsi_stop_channel_monitor(nc);
+
spin_lock_irqsave(&nc->lock, flags);
nc->state = NCSI_CHANNEL_INVISIBLE;
spin_unlock_irqrestore(&nc->lock, flags);
--
2.14.2