hugetlb: fix overcommit locking
proc_doulongvec_minmax() calls copy_to_user()/copy_from_user(), so we can't
hold hugetlb_lock over the call. Use a dummy variable to store the sysctl
result, like in hugetlb_sysctl_handler(), then grab the lock to update
nr_overcommit_huge_pages.
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Reported-by: Miles Lane <miles.lane@gmail.com>
Cc: Adam Litke <agl@us.ibm.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 7ca198b..addca4c 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -33,8 +33,8 @@
void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed);
extern unsigned long max_huge_pages;
+extern unsigned long sysctl_overcommit_huge_pages;
extern unsigned long hugepages_treat_as_movable;
-extern unsigned long nr_overcommit_huge_pages;
extern const unsigned long hugetlb_zero, hugetlb_infinity;
extern int sysctl_hugetlb_shm_group;