From: Christoph Hellwig <hch@lst.de>
Date: Sun, 17 Sep 2017 21:07:08 +0000 (-0700)
Subject: xfs: disable per-inode DAX flag
X-Git-Tag: archive/raspbian/4.9.51-1+rpi1~7^2~8
X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/%22/%22http:/www.example.com/cgi/%22?a=commitdiff_plain;h=0e8d7e364ec546c44762664d30f4b1f6fd912197;p=linux-4.9.git

xfs: disable per-inode DAX flag

commit 742d84290739ae908f1b61b7d17ea382c8c0073a upstream.

Currently flag switching can be used to easily crash the kernel.  Disable
the per-inode DAX flag until that is sorted out.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 73cfc7179124..be54216027b6 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -1005,11 +1005,12 @@ xfs_diflags_to_linux(
 		inode->i_flags |= S_NOATIME;
 	else
 		inode->i_flags &= ~S_NOATIME;
+#if 0	/* disabled until the flag switching races are sorted out */
 	if (xflags & FS_XFLAG_DAX)
 		inode->i_flags |= S_DAX;
 	else
 		inode->i_flags &= ~S_DAX;
-
+#endif
 }
 
 static int