Commit f3d815cb authored Dec 06, 2013 by Lans Zhang Committed by Ingo Molnar Dec 19, 2013

x86/mm/numa: Fix 32-bit kernel NUMA boot



When booting a 32-bit x86 kernel on a NUMA machine, node data
cannot be allocated from local node if the account of memory for
node 0 covers the low memory space entirely:

  [    0.000000] Initmem setup node 0 [mem 0x00000000-0x83fffffff]
  [    0.000000]   NODE_DATA [mem 0x367ed000-0x367edfff]
  [    0.000000] Initmem setup node 1 [mem 0x840000000-0xfffffffff]
  [    0.000000] Cannot find 4096 bytes in node 1
  [    0.000000] 64664MB HIGHMEM available.
  [    0.000000] 871MB LOWMEM available.

To fix this issue, node data is allowed to be allocated from
other nodes if the memory of local node is still not mapped. The
expected result looks like this:

  [    0.000000] Initmem setup node 0 [mem 0x00000000-0x83fffffff]
  [    0.000000]   NODE_DATA [mem 0x367ed000-0x367edfff]
  [    0.000000] Initmem setup node 1 [mem 0x840000000-0xfffffffff]
  [    0.000000]   NODE_DATA [mem 0x367ec000-0x367ecfff]
  [    0.000000]     NODE_DATA(1) on node 0
  [    0.000000] 64664MB HIGHMEM available.
  [    0.000000] 871MB LOWMEM available.

Signed-off-by: Lans Zhang <jia.zhang@windriver.com>
Cc: <andi@firstfloor.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1386303510-18574-1-git-send-email-jia.zhang@windriver.com


Signed-off-by: Ingo Molnar <mingo@kernel.org>

parent 3331e924

arch/x86/mm/numa.c

+7 −3

Original line number	Diff line number	Diff line
		@@ -210,11 +210,15 @@ static void __init setup_node_data(int nid, u64 start, u64 end)
		* Never allocate in DMA zone.
		*/
		nd_pa = memblock_alloc_nid(nd_size, SMP_CACHE_BYTES, nid);
		if (!nd_pa) {
		nd_pa = __memblock_alloc_base(nd_size, SMP_CACHE_BYTES,
		MEMBLOCK_ALLOC_ACCESSIBLE);
		if (!nd_pa) {
		pr_err("Cannot find %zu bytes in node %d\n",
		nd_size, nid);
		return;
		}
		}
		nd = __va(nd_pa);

		/* report and initialize */

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