diff options
| author | Hugh Dickins <hugh@veritas.com> | 2005-06-21 17:15:06 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-06-21 18:46:19 -0700 |
| commit | 941150a326be88af245034ef4b3e9fa00229aa2d (patch) | |
| tree | 03a058776dccd007150a3f57b1f36bf63b8f6a5d /mm | |
| parent | 400e65146c428d2ef677a927786fda2cec545a76 (diff) | |
| download | lwn-941150a326be88af245034ef4b3e9fa00229aa2d.tar.gz lwn-941150a326be88af245034ef4b3e9fa00229aa2d.zip | |
[PATCH] mbind: fix verify_pages pte_page
Strict mbind's check that pages already mapped are on right node has been
using pte_page without checking if pfn_valid, and without page_table_lock
to prevent spurious failures when try_to_unmap_one intervenes between the
pte_present and the pte_page.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/mempolicy.c | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 39252c732db2..c512cc911e22 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -242,6 +242,9 @@ static int verify_pages(struct mm_struct *mm, unsigned long addr, unsigned long end, unsigned long *nodes) { + int err = 0; + + spin_lock(&mm->page_table_lock); while (addr < end) { struct page *p; pte_t *pte; @@ -268,17 +271,23 @@ verify_pages(struct mm_struct *mm, } p = NULL; pte = pte_offset_map(pmd, addr); - if (pte_present(*pte)) - p = pte_page(*pte); + if (pte_present(*pte)) { + unsigned long pfn = pte_pfn(*pte); + if (pfn_valid(pfn)) + p = pfn_to_page(pfn); + } pte_unmap(pte); if (p) { unsigned nid = page_to_nid(p); - if (!test_bit(nid, nodes)) - return -EIO; + if (!test_bit(nid, nodes)) { + err = -EIO; + break; + } } addr += PAGE_SIZE; } - return 0; + spin_unlock(&mm->page_table_lock); + return err; } /* Step 1: check the range */ |