mm/sparse: more checks on mem_section number

__section_nr() was implemented to retrieve the corresponding memory
section number according to its descriptor.  It's possible that the
specified memory section descriptor doesn't exist in the global array.  So
add more checking on that and report an error for a wrong case.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Gavin Shan 2012-07-31 16:46:04 -07:00 committed by Linus Torvalds
parent 5b760e64a6
commit db36a46113

View file

@ -130,6 +130,8 @@ int __section_nr(struct mem_section* ms)
break;
}
VM_BUG_ON(root_nr == NR_SECTION_ROOTS);
return (root_nr * SECTIONS_PER_ROOT) + (ms - root);
}