mm: slab-allocate memory section nodemask for large systems

Nodemasks should not be allocated on the stack for large systems (when it
is larger than 256 bytes) since there is a threat of overflow.

This patch causes the unregister_mem_sect_under_nodes() nodemask to be
allocated on the stack for smaller systems and be allocated by slab for
larger systems.

GFP_KERNEL is used since remove_memory_block() can block.

Cc: Gary Hade <garyhade@us.ibm.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Alex Chiang <achiang@hp.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
David Rientjes 2009-12-14 17:59:46 -08:00 committed by Linus Torvalds
parent caed0f486e
commit 9ae49fab23

View file

@ -363,12 +363,16 @@ int register_mem_sect_under_node(struct memory_block *mem_blk, int nid)
/* unregister memory section under all nodes that it spans */ /* unregister memory section under all nodes that it spans */
int unregister_mem_sect_under_nodes(struct memory_block *mem_blk) int unregister_mem_sect_under_nodes(struct memory_block *mem_blk)
{ {
nodemask_t unlinked_nodes; NODEMASK_ALLOC(nodemask_t, unlinked_nodes, GFP_KERNEL);
unsigned long pfn, sect_start_pfn, sect_end_pfn; unsigned long pfn, sect_start_pfn, sect_end_pfn;
if (!mem_blk) if (!mem_blk) {
NODEMASK_FREE(unlinked_nodes);
return -EFAULT; return -EFAULT;
nodes_clear(unlinked_nodes); }
if (!unlinked_nodes)
return -ENOMEM;
nodes_clear(*unlinked_nodes);
sect_start_pfn = section_nr_to_pfn(mem_blk->phys_index); sect_start_pfn = section_nr_to_pfn(mem_blk->phys_index);
sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1; sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1;
for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) { for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
@ -379,13 +383,14 @@ int unregister_mem_sect_under_nodes(struct memory_block *mem_blk)
continue; continue;
if (!node_online(nid)) if (!node_online(nid))
continue; continue;
if (node_test_and_set(nid, unlinked_nodes)) if (node_test_and_set(nid, *unlinked_nodes))
continue; continue;
sysfs_remove_link(&node_devices[nid].sysdev.kobj, sysfs_remove_link(&node_devices[nid].sysdev.kobj,
kobject_name(&mem_blk->sysdev.kobj)); kobject_name(&mem_blk->sysdev.kobj));
sysfs_remove_link(&mem_blk->sysdev.kobj, sysfs_remove_link(&mem_blk->sysdev.kobj,
kobject_name(&node_devices[nid].sysdev.kobj)); kobject_name(&node_devices[nid].sysdev.kobj));
} }
NODEMASK_FREE(unlinked_nodes);
return 0; return 0;
} }