[PATCH 2/2] edac: edac_device: don't re-arm workqueue during teardown

[Jad Keskes <inasj268@gmail.com>]

edac_device_del_device stops the workqueue then removes the sysfs
attributes.  But the sysfs store for poll_msec calls
edac_device_reset_delay_period which unconditionally re-arms the
workqueue.  If someone writes to poll_msec in that window, the
re-armed work runs after edac_dev is freed.

Check op_state instead.  del_device already sets it to OP_OFFLINE
before tearing down the workqueue, so reset_delay_period will see
it and skip the mod_work call.

Signed-off-by: Jad Keskes <inasj268@gmail.com>
---
 drivers/edac/edac_device.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/edac/edac_device.c b/drivers/edac/edac_device.c
index cf0d3c2dfc04..50ae7f1e5152 100644
--- a/drivers/edac/edac_device.c
+++ b/drivers/edac/edac_device.c
@@ -354,6 +354,10 @@ void edac_device_reset_delay_period(struct edac_device_ctl_info *edac_dev,
 	edac_dev->poll_msec = msec;
 	edac_dev->delay	    = msecs_to_jiffies(msec);
 
+	/* Don't re-arm the workqueue if the device is being torn down */
+	if (edac_dev->op_state == OP_OFFLINE)
+		return;
+
 	/* See comment in edac_device_workq_setup() above */
 	if (edac_dev->poll_msec == DEFAULT_POLL_INTERVAL)
 		edac_mod_work(&edac_dev->work, round_jiffies_relative(edac_dev->delay));
-- 
2.55.0