@@ -517,13 +517,16 @@ writeback_single_inode(struct inode *inode, struct bdi_writeback *wb,
}
WARN_ON(inode->i_state & I_SYNC);
/*
- * Skip inode if it is clean. We don't want to mess with writeback
- * lists in this function since flusher thread may be doing for example
- * sync in parallel and if we move the inode, it could get skipped. So
- * here we make sure inode is on some writeback list and leave it there
- * unless we have completely cleaned the inode.
+ * Skip inode if it is clean and we have no outstanding writeback in
+ * WB_SYNC_ALL mode. We don't want to mess with writeback lists in this
+ * function since flusher thread may be doing for example sync in
+ * parallel and if we move the inode, it could get skipped. So here we
+ * make sure inode is on some writeback list and leave it there unless
+ * we have completely cleaned the inode.
*/
- if (!(inode->i_state & I_DIRTY))
+ if (!(inode->i_state & I_DIRTY) &&
+ (wbc->sync_mode != WB_SYNC_ALL ||
+ !mapping_tagged(inode->i_mapping, PAGECACHE_TAG_WRITEBACK)))
goto out;
inode->i_state |= I_SYNC;
spin_unlock(&inode->i_lock);
This is a note to let you know that I have just added a patch titled writeback: Fix data corruption on NFS to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue This patch is scheduled to be released in version 3.8.13.17. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.8.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From ecaa777530172df56bf1f0c3e76cb1806eb7effe Mon Sep 17 00:00:00 2001 From: Jan Kara <jack@suse.cz> Date: Sat, 14 Dec 2013 04:21:26 +0800 Subject: writeback: Fix data corruption on NFS commit f9b0e058cbd04ada76b13afffa7e1df830543c24 upstream. Commit 4f8ad655dbc8 "writeback: Refactor writeback_single_inode()" added a condition to skip clean inode. However this is wrong in WB_SYNC_ALL mode because there we also want to wait for outstanding writeback on possibly clean inode. This was causing occasional data corruption issues on NFS because it uses sync_inode() to make sure all outstanding writes are flushed to the server before truncating the inode and with sync_inode() returning prematurely file was sometimes extended back by an outstanding write after it was truncated. So modify the test to also check for pages under writeback in WB_SYNC_ALL mode. Fixes: 4f8ad655dbc82cf05d2edc11e66b78a42d38bf93 Reported-and-tested-by: Dan Duval <dan.duval@oracle.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- fs/fs-writeback.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) -- 1.8.3.2