Commit cc9aec03e58f ("x86/numa_emulation: Introduce uniform split
capability") uses "-1" as the starting node ID, which causes the
strange kernel log as following, when "numa=fake=32G" is added to the
kernel command line.

    Faking node -1 at [mem 0x0000000000000000-0x0000000893ffffff] (35136MB)
    Faking node 0 at [mem 0x0000001840000000-0x000000203fffffff] (32768MB)
    Faking node 1 at [mem 0x0000000894000000-0x000000183fffffff] (64192MB)
    Faking node 2 at [mem 0x0000002040000000-0x000000283fffffff] (32768MB)
    Faking node 3 at [mem 0x0000002840000000-0x000000303fffffff] (32768MB)

And finally kernel BUG as following,

    BUG: Bad page state in process swapper  pfn:00011
    page:(____ptrval____) refcount:0 mapcount:1 mapping:(____ptrval____) 
index:0x55cd7e44b270 pfn:0x11
    failed to read mapping contents, not a valid kernel address?
    flags: 0x5(locked|uptodate)
    raw: 0000000000000005 000055cd7e44af30 000055cd7e44af50 0000000100000006
    raw: 000055cd7e44b270 000055cd7e44b290 0000000000000000 000055cd7e44b510
    page dumped because: page still charged to cgroup
    page->mem_cgroup:000055cd7e44b510
    Modules linked in:
    CPU: 0 PID: 0 Comm: swapper Not tainted 5.9.0-rc2 #1
    Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS 
SE5C620.86B.02.01.0008.031920191559 03/19/2019
    Call Trace:
     dump_stack+0x57/0x80
     bad_page.cold+0x63/0x94
     __free_pages_ok+0x33f/0x360
     memblock_free_all+0x127/0x195
     mem_init+0x23/0x1f5
     start_kernel+0x219/0x4f5
     secondary_startup_64+0xb6/0xc0

Fixes this bug via using 0 as the starting node ID.  This restores the
original behavior before the commit cc9aec03e58f ("x86/numa_emulation:
Introduce uniform split capability").

Fixes: cc9aec03e58f ("x86/numa_emulation: Introduce uniform split capability")
Signed-off-by: "Huang, Ying" <ying.hu...@intel.com>
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: Dave Hansen <dave.han...@linux.intel.com>
Cc: Andy Lutomirski <l...@kernel.org>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Ingo Molnar <mi...@redhat.com>
Cc: Borislav Petkov <b...@alien8.de>
Cc: x...@kernel.org
Cc: "H. Peter Anvin" <h...@zytor.com>
Cc: Dan Williams <dan.j.willi...@intel.com>
Cc: David Rientjes <rient...@google.com>
Cc: Dave Jiang <dave.ji...@intel.com>
---
 arch/x86/mm/numa_emulation.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/mm/numa_emulation.c b/arch/x86/mm/numa_emulation.c
index c5174b4e318b..683cd12f4793 100644
--- a/arch/x86/mm/numa_emulation.c
+++ b/arch/x86/mm/numa_emulation.c
@@ -321,7 +321,7 @@ static int __init split_nodes_size_interleave(struct 
numa_meminfo *ei,
                                              u64 addr, u64 max_addr, u64 size)
 {
        return split_nodes_size_interleave_uniform(ei, pi, addr, max_addr, size,
-                       0, NULL, NUMA_NO_NODE);
+                       0, NULL, 0);
 }
 
 static int __init setup_emu2phys_nid(int *dfl_phys_nid)
-- 
2.28.0

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