Commit 85770ffe authored Aug 22, 2007 by Andy Whitcroft Committed by Linus Torvalds Aug 22, 2007

sparsemem: ensure we initialise the node mapping for SPARSEMEM_STATIC



Booting SPARSEMEM on NUMA systems trips a BUG in page_alloc.c:

	Initializing HighMem for node 0 (00038000:00100000)
	Initializing HighMem for node 1 (00100000:001ffe00)
	------------[ cut here ]------------
	kernel BUG at /home/apw/git/linux-2.6/mm/page_alloc.c:456!
	[...]

This occurs because the section to node id mapping is not being
setup correctly during init under SPARSEMEM_STATIC, leading to an
attempt to free pages from all nodes into the zones on node 0.

When the zone_table[] was removed in the following commit, a new
section to node mapping table was introduced:

    commit 89689ae7
    [PATCH] Get rid of zone_table[]

That conversion inadvertantly only initialised the node mapping in
SPARSEMEM_EXTREME.  Ensure we initialise the node mapping in
SPARSEMEM_STATIC.

[akpm@linux-foundation.org: make the stubs static inline]
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent df068464

mm/sparse.c

+10 −4

Original line number	Diff line number	Diff line
		@@ -41,6 +41,15 @@ int page_to_nid(struct page *page)
		return section_to_node_table[page_to_section(page)];
		}
		EXPORT_SYMBOL(page_to_nid);

		static void set_section_nid(unsigned long section_nr, int nid)
		{
		section_to_node_table[section_nr] = nid;
		}
		#else /* !NODE_NOT_IN_PAGE_FLAGS */
		static inline void set_section_nid(unsigned long section_nr, int nid)
		{
		}
		#endif

		#ifdef CONFIG_SPARSEMEM_EXTREME
		@@ -68,10 +77,6 @@ static int __meminit sparse_index_init(unsigned long section_nr, int nid)
		struct mem_section *section;
		int ret = 0;

		#ifdef NODE_NOT_IN_PAGE_FLAGS
		section_to_node_table[section_nr] = nid;
		#endif

		if (mem_section[root])
		return -EEXIST;

		@@ -148,6 +153,7 @@ void __init memory_present(int nid, unsigned long start, unsigned long end)
		struct mem_section *ms;

		sparse_index_init(section, nid);
		set_section_nid(section, nid);

		ms = __nr_to_section(section);
		if (!ms->section_mem_map)

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