From 190f38e5cedc910940b1da9015f00458c18f97b4 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Thu, 10 Dec 2009 09:05:55 -0500 Subject: [PATCH] NFS: Fix nfs_migrate_page() The call to migrate_page() will cause the page->private field to be cleared. Also fix up the locking around the page->private transfer, so that we ensure that calls to nfs_page_find_request() don't end up racing. Finally, fix up a double free bug: nfs_unlock_request() already calls nfs_release_request() for us... Reported-by: Wu Fengguang Tested-by: Andi Kleen Cc: stable@kernel.org Signed-off-by: Trond Myklebust --- fs/nfs/write.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/nfs/write.c b/fs/nfs/write.c index a28123be08a6..6d40a538e3db 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -1611,15 +1611,16 @@ int nfs_migrate_page(struct address_space *mapping, struct page *newpage, if (ret) goto out_unlock; page_cache_get(newpage); + spin_lock(&mapping->host->i_lock); req->wb_page = newpage; SetPagePrivate(newpage); - set_page_private(newpage, page_private(page)); + set_page_private(newpage, (unsigned long)req); ClearPagePrivate(page); set_page_private(page, 0); + spin_unlock(&mapping->host->i_lock); page_cache_release(page); out_unlock: nfs_clear_page_tag_locked(req); - nfs_release_request(req); out: return ret; }