From: Fan Du <fan.du@xxxxxxxxx> The index of numa_meminfo is expected to the same as of numa_meminfo.blk[]. and numa_remove_memblk_from break the expectation. 2S system does not break, because before numa_remove_memblk_from index nid 0 0 1 1 after numa_remove_memblk_from index nid 0 1 1 1 If you try to configure uniform fake node in 4S system. index nid 0 0 1 1 2 2 3 3 node 3 will be removed by numa_remove_memblk_from when iterate index 2. so we only create fake node for 3 physcial node, and a portion of memroy wasted as much as it hit lost pages checking in numa_meminfo_cover_memory. Signed-off-by: Fan Du <fan.du@xxxxxxxxx> --- arch/x86/mm/numa_emulation.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) --- linux.orig/arch/x86/mm/numa_emulation.c 2018-12-23 19:20:51.570664269 +0800 +++ linux/arch/x86/mm/numa_emulation.c 2018-12-23 19:20:51.566664364 +0800 @@ -381,7 +381,21 @@ void __init numa_emulation(struct numa_m goto no_emu; memset(&ei, 0, sizeof(ei)); - pi = *numa_meminfo; + + { + /* Make sure the index is identical with nid */ + struct numa_meminfo *mi = numa_meminfo; + int nid; + + for (i = 0; i < mi->nr_blks; i++) { + nid = mi->blk[i].nid; + pi.blk[nid].nid = nid; + pi.blk[nid].start = mi->blk[i].start; + pi.blk[nid].end = mi->blk[i].end; + } + pi.nr_blks = mi->nr_blks; + + } for (i = 0; i < MAX_NUMNODES; i++) emu_nid_to_phys[i] = NUMA_NO_NODE;