ocfs2: release page lock before calling ->page_mkwrite
__do_fault() was calling ->page_mkwrite() with the page lock held, which
violates the locking rules for that callback. Release and retake the page
lock around the callback to avoid deadlocking file systems which manually
take it.
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/memory.c b/mm/memory.c
index eee7fec..7abd389 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2369,11 +2369,14 @@
* address space wants to know that the page is about
* to become writable
*/
- if (vma->vm_ops->page_mkwrite &&
- vma->vm_ops->page_mkwrite(vma, page) < 0) {
- fdata.type = VM_FAULT_SIGBUS;
- anon = 1; /* no anon but release faulted_page */
- goto out;
+ if (vma->vm_ops->page_mkwrite) {
+ unlock_page(page);
+ if (vma->vm_ops->page_mkwrite(vma, page) < 0) {
+ fdata.type = VM_FAULT_SIGBUS;
+ anon = 1; /* no anon but release faulted_page */
+ goto out_unlocked;
+ }
+ lock_page(page);
}
}
@@ -2425,6 +2428,7 @@
out:
unlock_page(faulted_page);
+out_unlocked:
if (anon)
page_cache_release(faulted_page);
else if (dirty_page) {