From: Christoph Lameter Date: Fri, 17 Mar 2006 07:03:59 +0000 (-0800) Subject: [PATCH] page migration: Fail with error if swap not setup X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=90036ee5938d89638e80f4d0d0700d0f2dbd4a6a;p=GitHub%2FLineageOS%2Fandroid_kernel_samsung_universal7580.git [PATCH] page migration: Fail with error if swap not setup Currently the migration of anonymous pages will silently fail if no swap is setup. This patch makes page migration functions check for available swap and fail with -ENODEV if no swap space is available. Signed-off-by: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 2a820600942..b21869a39f0 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -330,9 +330,19 @@ check_range(struct mm_struct *mm, unsigned long start, unsigned long end, int err; struct vm_area_struct *first, *vma, *prev; - /* Clear the LRU lists so pages can be isolated */ - if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) + if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) { + /* Must have swap device for migration */ + if (nr_swap_pages <= 0) + return ERR_PTR(-ENODEV); + + /* + * Clear the LRU lists so pages can be isolated. + * Note that pages may be moved off the LRU after we have + * drained them. Those pages will fail to migrate like other + * pages that may be busy. + */ lru_add_drain_all(); + } first = find_vma(mm, start); if (!first)