Changelog:
 *v2 -> v3: revert commit d157a558 directly

The VM_UNINITIALIZED/VM_UNLIST flag introduced by commit f5252e00(mm: avoid
null pointer access in vm_struct via /proc/vmallocinfo) is used to avoid
accessing the pages field with unallocated page when show_numa_info() is
called. This patch move the check just before show_numa_info in order that
some messages still can be dumped via /proc/vmallocinfo. This patch revert 
commit d157a558 (mm/vmalloc.c: check VM_UNINITIALIZED flag in s_show instead 
of show_numa_info);

Reviewed-by: Zhang Yanfei <zhangyan...@cn.fujitsu.com>
Signed-off-by: Wanpeng Li <liw...@linux.vnet.ibm.com>
---
 mm/vmalloc.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index e3ec8b4..5368b17 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2562,6 +2562,11 @@ static void show_numa_info(struct seq_file *m, struct 
vm_struct *v)
                if (!counters)
                        return;
 
+               /* Pair with smp_wmb() in clear_vm_uninitialized_flag() */
+               smp_rmb();
+               if (v->flags & VM_UNINITIALIZED)
+                       return;
+
                memset(counters, 0, nr_node_ids * sizeof(unsigned int));
 
                for (nr = 0; nr < v->nr_pages; nr++)
@@ -2590,11 +2595,6 @@ static int s_show(struct seq_file *m, void *p)
 
        v = va->vm;
 
-       /* Pair with smp_wmb() in clear_vm_uninitialized_flag() */
-       smp_rmb();
-       if (v->flags & VM_UNINITIALIZED)
-               return 0;
-
        seq_printf(m, "0x%pK-0x%pK %7ld",
                v->addr, v->addr + v->size, v->size);
 
-- 
1.8.1.2

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