[PATCH v2 2/6] net: dsa: Do not reschedule polling if driver removed

Neil Armstrong
2015-10-29T13:24:35Z

Do not reschedule the delayed work used for polling when
the driver is removed, by testing the 'poll_link_needed'
flag.
Avoids this crash:
dsa dsa ethmv2 (unregistering): Link is Down
device eth1 left promiscuous mode
Unable to handle kernel paging request at virtual address bacc5cf6
...
(run_timer_softirq) from [<c003e810>] (__do_softirq+0xcc/0x320)
(__do_softirq) from [<c003ed40>] (irq_exit+0xac/0x10c)
(irq_exit) from [<c007ec20>] (__handle_domain_irq+0x50/0xa8)

Signed-off-by: Frode Isaksen <fisaksen@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
---
net/dsa/dsa.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index aeb6a7c..19cff8f 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -522,7 +522,8 @@ static void dsa_link_poll_work(struct work_struct *ugly)
ds->drv->poll_link(ds);
}

- schedule_delayed_work(&dst->link_poll_work, round_jiffies_relative(HZ));
+ if (dst->link_poll_needed)
+ schedule_delayed_work(&dst->link_poll_work, round_jiffies_relative(HZ));
}

/* platform driver init and cleanup *****************************************/
@@ -943,6 +944,7 @@ static void dsa_remove_dst(struct dsa_switch_tree *dst)
int i;

if (dst->link_poll_needed) {
+ dst->link_poll_needed = 0;
cancel_delayed_work_sync(&dst->link_poll_work);
flush_delayed_work(&dst->link_poll_work);
}
--
1.9.1