early_pfn_to_nid can return node 0 if a PFN is invalid on machines
that has no node 0. A machine with only node 1 was observed to crash
with the following message
BUG: unable to handle kernel paging request at 000000000002a3c8
PGD 0
Modules linked in:
Hardware name: Supermicro H8DSP-8/H8DSP-8, BIOS 080011 06/30/2006
task: ffffffff81c0d500 ti: ffffffff81c00000 task.ti: ffffffff81c00000
RIP: 0010:[<ffffffff816dbd63>] [<ffffffff816dbd63>]
reserve_bootmem_region+0x6a/0xef
RSP: 0000:ffffffff81c03eb0 EFLAGS: 00010086
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffffffff81c03ec0 RSI: ffffffff81d205c0 RDI: ffffffff8213ee60
R13: ffffea0000000000 R14: ffffea0000000020 R15: ffffea0000000020
FS: 0000000000000000(0000) GS:ffff8800fba00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000002a3c8 CR3: 0000000001c06000 CR4: 00000000000006b0
Stack:
ffffffff81c03f00 0000000000000400 ffff8800fbfc3200 ffffffff81e2a2c0
ffffffff81c03fb0 ffffffff81c03f20 ffffffff81dadf7d ffffea0002000040
ffffea0000000000 0000000000000000 000000000000ffff 0000000000000001
Call Trace:
[<ffffffff81dadf7d>] free_all_bootmem+0x4b/0x12a
[<ffffffff81d97122>] mem_init+0x70/0xa3
[<ffffffff81d78f21>] start_kernel+0x25b/0x49b
The problem is that early_page_uninitialised uses the early_pfn_to_nid
helper which returns node 0 for invalid PFNs. No caller of early_pfn_to_nid
cares except early_page_uninitialised. This patch has early_pfn_to_nid
always return a valid node.
Signed-off-by: Mel Gorman <mgor...@techsingularity.net>
Cc: <sta...@vger.kernel.org> # 4.2+
---
mm/page_alloc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index a19527aa4243..5a616de1adca 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1097,7 +1097,7 @@ int __meminit early_pfn_to_nid(unsigned long pfn)
spin_lock(&early_pfn_lock);
nid = __early_pfn_to_nid(pfn, &early_pfnnid_cache);
if (nid < 0)
- nid = 0;
+ nid = first_online_node;
spin_unlock(&early_pfn_lock);
return nid;
--
2.6.4
