Commit 41e3355d authored Apr 08, 2008 by KAMEZAWA Hiroyuki Committed by Linus Torvalds Apr 08, 2008

memcg: fix node_state handling



This should be N_NORMAL_MEMORY.

N_NORMAL_MEMORY is "true" if a node has memory for the kernel.  N_HIGH_MEMORY
is "true" if a node has memory for HIGHMEM.  (If CONFIG_HIGHMEM=n, always
"true")

This check is used for testing whether we can use kmalloc_node() on a node.
Then, if there is a node which only contains HIGHMEM, the system will call
kmalloc_node() which doesn't contain memory for the kernel.  If it happens
under SLUB, the kernel will panic.  I think this only happens on x86_32-numa.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent bb070e43

mm/memcontrol.c

+4 −5

Original line number	Diff line number	Diff line
		@@ -978,7 +978,7 @@ static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node)
		{
		struct mem_cgroup_per_node *pn;
		struct mem_cgroup_per_zone *mz;
		int zone;
		int zone, tmp = node;
		/*
		* This routine is called against possible nodes.
		* But it's BUG to call kmalloc() against offline node.
		@@ -987,10 +987,9 @@ static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node)
		* never be onlined. It's better to use memory hotplug callback
		* function.
		*/
		if (node_state(node, N_HIGH_MEMORY))
		pn = kmalloc_node(sizeof(*pn), GFP_KERNEL, node);
		else
		pn = kmalloc(sizeof(*pn), GFP_KERNEL);
		if (!node_state(node, N_NORMAL_MEMORY))
		tmp = -1;
		pn = kmalloc_node(sizeof(*pn), GFP_KERNEL, tmp);
		if (!pn)
		return 1;