From 064d9efe947542097be669581f82d6b097e81d1a Mon Sep 17 00:00:00 2001 From: Nishanth Aravamudan Date: Wed, 13 Feb 2008 15:03:19 -0800 Subject: 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 Reported-by: Miles Lane Cc: Adam Litke Cc: David Gibson Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/hugetlb.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'mm') diff --git a/mm/hugetlb.c b/mm/hugetlb.c index d9a380312467..cb1b3a7ecdfc 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -24,14 +24,15 @@ const unsigned long hugetlb_zero = 0, hugetlb_infinity = ~0UL; static unsigned long nr_huge_pages, free_huge_pages, resv_huge_pages; static unsigned long surplus_huge_pages; +static unsigned long nr_overcommit_huge_pages; unsigned long max_huge_pages; +unsigned long sysctl_overcommit_huge_pages; static struct list_head hugepage_freelists[MAX_NUMNODES]; static unsigned int nr_huge_pages_node[MAX_NUMNODES]; static unsigned int free_huge_pages_node[MAX_NUMNODES]; static unsigned int surplus_huge_pages_node[MAX_NUMNODES]; static gfp_t htlb_alloc_mask = GFP_HIGHUSER; unsigned long hugepages_treat_as_movable; -unsigned long nr_overcommit_huge_pages; static int hugetlb_next_nid; /* @@ -609,8 +610,9 @@ int hugetlb_overcommit_handler(struct ctl_table *table, int write, struct file *file, void __user *buffer, size_t *length, loff_t *ppos) { - spin_lock(&hugetlb_lock); proc_doulongvec_minmax(table, write, file, buffer, length, ppos); + spin_lock(&hugetlb_lock); + nr_overcommit_huge_pages = sysctl_overcommit_huge_pages; spin_unlock(&hugetlb_lock); return 0; } -- cgit v1.2.2