diff options
| author | Jan Kara <jack@suse.cz> | 2016-12-14 15:07:50 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-14 16:04:09 -0800 |
| commit | 2f89dc12a25ddf995b9acd7b6543fe892e3473d6 (patch) | |
| tree | d162312aa8bdcb6602a9c30dd5810c0f2f8e0a16 /mm | |
| parent | a6abc2c0e77b16480f4d2c1eb7925e5287ae1526 (diff) | |
dax: protect PTE modification on WP fault by radix tree entry lock
Currently PTE gets updated in wp_pfn_shared() after dax_pfn_mkwrite()
has released corresponding radix tree entry lock. When we want to
writeprotect PTE on cache flush, we need PTE modification to happen
under radix tree entry lock to ensure consistent updates of PTE and
radix tree (standard faults use page lock to ensure this consistency).
So move update of PTE bit into dax_pfn_mkwrite().
Link: http://lkml.kernel.org/r/1479460644-25076-20-git-send-email-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/memory.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/memory.c b/mm/memory.c index edd899d0decb..57d0bd1bd2c4 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2315,7 +2315,7 @@ static int wp_pfn_shared(struct vm_fault *vmf) pte_unmap_unlock(vmf->pte, vmf->ptl); vmf->flags |= FAULT_FLAG_MKWRITE; ret = vma->vm_ops->pfn_mkwrite(vma, vmf); - if (ret & VM_FAULT_ERROR) + if (ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE)) return ret; return finish_mkwrite_fault(vmf); } |