Don't only specify munmap(2) behavior with respect the hugetlb memory, all other syscalls get naturally aligned to the native page size of the processor. Rather, pick out munmap(2) as a specific example. Signed-off-by: David Rientjes <rientjes@xxxxxxxxxx> --- Documentation/vm/hugetlbpage.txt | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/Documentation/vm/hugetlbpage.txt b/Documentation/vm/hugetlbpage.txt index 1270fb1..030977f 100644 --- a/Documentation/vm/hugetlbpage.txt +++ b/Documentation/vm/hugetlbpage.txt @@ -313,8 +313,11 @@ into /proc/sys/vm/hugetlb_shm_group. It is possible for same or different applications to use any combination of mmaps and shm* calls, though the mount of filesystem will be required for using mmap calls without MAP_HUGETLB. -When using munmap(2) to unmap hugetlb memory, the length specified must be -hugepage aligned, otherwise it will fail with errno set to EINVAL. +Syscalls that operate on memory backed by hugetlb pages only have their lengths +aligned to the native page size of the processor; they will normally fail with +errno set to EINVAL or exclude hugetlb pages that extend beyond the length if +not hugepage aligned. For example, munmap(2) will fail if memory is backed by +a hugetlb page and the length is smaller than the hugepage size. Examples -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>