Ignore madvise(MADV_WILLNEED) for hugetlbfs-backed regions
madvise(MADV_WILLNEED) forces page cache readahead on a range of memory backed by a file. The assumption is made that the page required is order-0 and "normal" page cache. On hugetlbfs, this assumption is not true and order-0 pages are allocated and inserted into the hugetlbfs page cache. This leaks hugetlbfs page reservations and can cause BUGs to trigger related to corrupted page tables. This patch causes MADV_WILLNEED to be ignored for hugetlbfs-backed regions. Signed-off-by: Mel Gorman <mel@csn.ul.ie> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
99ee12973e
commit
a425a638c8
|
@ -112,6 +112,14 @@ static long madvise_willneed(struct vm_area_struct * vma,
|
||||||
if (!file)
|
if (!file)
|
||||||
return -EBADF;
|
return -EBADF;
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Page cache readahead assumes page cache pages are order-0 which
|
||||||
|
* is not the case for hugetlbfs. Do not give a bad return value
|
||||||
|
* but ignore the advice.
|
||||||
|
*/
|
||||||
|
if (vma->vm_flags & VM_HUGETLB)
|
||||||
|
return 0;
|
||||||
|
|
||||||
if (file->f_mapping->a_ops->get_xip_mem) {
|
if (file->f_mapping->a_ops->get_xip_mem) {
|
||||||
/* no bad return value, but ignore advice */
|
/* no bad return value, but ignore advice */
|
||||||
return 0;
|
return 0;
|
||||||
|
|
Loading…
Reference in New Issue