node-hotplug: is memset 0 safe in try_offline_node()?

From: Xishi Qiu
Date: Mon Mar 02 2015 - 22:30:45 EST


When hot-remove a numa node, we will clear pgdat,
but is memset 0 safe in try_offline_node()?

process A: offline node XX:
for_each_populated_zone()
find online node XX
cond_resched()
offline cpu and memory, then try_offline_node()
node_set_offline(nid), and memset(pgdat, 0, sizeof(*pgdat))
access node XX's pgdat
NULL pointer access error

Thanks,
Xishi Qiu

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/