OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

thp: pmd_trans_huge migrate bugcheck 

No pmd_trans_huge should ever materialize in migration ptes areas, because
we split the hugepage before migration ptes are instantiated.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Andrea Arcangeli 2011-01-13 15:46:55 -08:00 committed by Linus Torvalds
parent 0af4e98b6b
commit 500d65d471
3 changed files with 12 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
include/linux/mm.h
View File

@ -1490,6 +1490,7 @@ struct page *follow_page(struct vm_area_struct *, unsigned long address,
#define FOLL_DUMP 0x08 /* give error on hole if it would be zero */
#define FOLL_FORCE 0x10 /* get_user_pages read/write w/o permission */
#define FOLL_MLOCK 0x40 /* mark page as mlocked */
#define FOLL_SPLIT 0x80 /* don't return transhuge pages, split them */
typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr,
void *data);

5
mm/memory.c
View File

@ -1305,6 +1305,10 @@ struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
goto out;
}
if (pmd_trans_huge(*pmd)) {
if (flags & FOLL_SPLIT) {
split_huge_page_pmd(mm, pmd);
goto split_fallthrough;
}
spin_lock(&mm->page_table_lock);
if (likely(pmd_trans_huge(*pmd))) {
if (unlikely(pmd_trans_splitting(*pmd))) {
@ -1320,6 +1324,7 @@ struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
spin_unlock(&mm->page_table_lock);
/* fall through */
}
split_fallthrough:
if (unlikely(pmd_bad(*pmd)))
goto no_page_table;

7
mm/migrate.c
View File

@ -113,6 +113,8 @@ static int remove_migration_pte(struct page *new, struct vm_area_struct *vma,
goto out;
pmd = pmd_offset(pud, addr);
if (pmd_trans_huge(*pmd))
goto out;
if (!pmd_present(*pmd))
goto out;
@ -632,6 +634,9 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
/* page was freed from under us. So we are done. */
goto move_newpage;
}
if (unlikely(PageTransHuge(page)))
if (unlikely(split_huge_page(page)))
goto move_newpage;
/* prepare cgroup just returns 0 or -ENOMEM */
rc = -EAGAIN;
@ -1063,7 +1068,7 @@ static int do_move_page_to_node_array(struct mm_struct *mm,
if (!vma || pp->addr < vma->vm_start || !vma_migratable(vma))
goto set_status;
page = follow_page(vma, pp->addr, FOLL_GET);
page = follow_page(vma, pp->addr, FOLL_GET|FOLL_SPLIT);
err = PTR_ERR(page);
if (IS_ERR(page))