Commit af12346c authored by Wanpeng Li's avatar Wanpeng Li Committed by Linus Torvalds

mm/vmalloc: revert "mm/vmalloc.c: check VM_UNINITIALIZED flag in s_show instead of show_numa_info"

The VM_UNINITIALIZED/VM_UNLIST flag introduced by 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 moves the check just before show_numa_info in order that some
messages still can be dumped via /proc/vmallocinfo.  This patch reverts
commit d157a558 ("mm/vmalloc.c: check VM_UNINITIALIZED flag in
s_show instead of show_numa_info");
Reviewed-by: default avatarZhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: default avatarWanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent c2ce8c14
...@@ -2562,6 +2562,11 @@ static void show_numa_info(struct seq_file *m, struct vm_struct *v) ...@@ -2562,6 +2562,11 @@ static void show_numa_info(struct seq_file *m, struct vm_struct *v)
if (!counters) if (!counters)
return; 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)); memset(counters, 0, nr_node_ids * sizeof(unsigned int));
for (nr = 0; nr < v->nr_pages; nr++) for (nr = 0; nr < v->nr_pages; nr++)
...@@ -2587,11 +2592,6 @@ static int s_show(struct seq_file *m, void *p) ...@@ -2587,11 +2592,6 @@ static int s_show(struct seq_file *m, void *p)
v = va->vm; 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", seq_printf(m, "0x%pK-0x%pK %7ld",
v->addr, v->addr + v->size, v->size); v->addr, v->addr + v->size, v->size);
......
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