memory hotplug: fix early allocation handling
Trying to add memory via add_memory() from within an initcall function
results in
bootmem alloc of 163840 bytes failed!
Kernel panic - not syncing: Out of memory
This is caused by zone_wait_table_init() which uses system_state to decide
if it should use the bootmem allocator or not.
When initcalls are handled the system_state is still SYSTEM_BOOTING but
the bootmem allocator doesn't work anymore. So the allocation will fail.
To fix this use slab_is_available() instead as indicator like we do it
everywhere else.
[akpm@linux-foundation.org: coding-style fix]
Reviewed-by: Andy Whitcroft <apw@shadowen.org>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 7f4c66f..8e83f02 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2807,7 +2807,7 @@
alloc_size = zone->wait_table_hash_nr_entries
* sizeof(wait_queue_head_t);
- if (system_state == SYSTEM_BOOTING) {
+ if (!slab_is_available()) {
zone->wait_table = (wait_queue_head_t *)
alloc_bootmem_node(pgdat, alloc_size);
} else {
