4.15-stable review patch. If anyone has any objections, please let me know.
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From: Amir Goldstein amir73il@gmail.com
commit acd1d71598f7654b6d7718bcbe979992295c672a upstream.
Commit 66f364649d870 ("xfs: remove if_rdev") moved storing of rdev value for special inodes to VFS inodes, but forgot to preserve the value of i_rdev when recycling a reclaimable xfs_inode.
This was detected by xfstest overlay/017 with inodex=on mount option and xfs base fs. The test does a lookup of overlay chardev and blockdev right after drop caches.
Overlayfs inodes hold a reference on underlying xfs inodes when mount option index=on is configured. If drop caches reclaim xfs inodes, before it relclaims overlayfs inodes, that can sometimes leave a reclaimable xfs inode and that test hits that case quite often.
When that happens, the xfs inode cache remains broken (zere i_rdev) until the next cycle mount or drop caches.
Fixes: 66f364649d870 ("xfs: remove if_rdev") Signed-off-by: Amir Goldstein amir73il@gmail.com Reviewed-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
--- fs/xfs/xfs_icache.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/fs/xfs/xfs_icache.c +++ b/fs/xfs/xfs_icache.c @@ -295,6 +295,7 @@ xfs_reinit_inode( uint32_t generation = inode->i_generation; uint64_t version = inode->i_version; umode_t mode = inode->i_mode; + dev_t dev = inode->i_rdev;
error = inode_init_always(mp->m_super, inode);
@@ -302,6 +303,7 @@ xfs_reinit_inode( inode->i_generation = generation; inode->i_version = version; inode->i_mode = mode; + inode->i_rdev = dev; return error; }