From: Darrick J. Wong <darrick.wong@xxxxxxxxxx> In inode_init_always(), we clear the inode mapping flags, which clears any retained error (AS_EIO, AS_ENOSC) bits. Unfortunately, we do not also clear wb_err, which means that old mapping errors can leak through to new inodes. This is crucial for the XFS inode allocation path because we recycle old in-core inodes and we do not want error state from an old file to leak into the new file. This bug was discovered by running generic/036 and generic/047 in a loop and noticing that the EIOs generated by the collision of direct and buffered writes in generic/036 would survive the remount between 036 and 047, and get reported to the fsyncs (on different files on a reformatted fs!) in generic/047. Since we're changing the semantics of inode_init_always, we must also change xfs_reinit_inode to retain the writeback error state when we go to recover an inode that has been torn down in the vfs but not yet disposed of by XFS. Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> --- fs/inode.c | 1 + fs/xfs/xfs_icache.c | 2 ++ 2 files changed, 3 insertions(+) diff --git a/fs/inode.c b/fs/inode.c index 13ceb98c3bd3..3b55391072f3 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -178,6 +178,7 @@ int inode_init_always(struct super_block *sb, struct inode *inode) mapping->a_ops = &empty_aops; mapping->host = inode; mapping->flags = 0; + mapping->wb_err = 0; atomic_set(&mapping->i_mmap_writable, 0); mapping_set_gfp_mask(mapping, GFP_HIGHUSER_MOVABLE); mapping->private_data = NULL; diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c index 164350d91efc..f4d672cb60a4 100644 --- a/fs/xfs/xfs_icache.c +++ b/fs/xfs/xfs_icache.c @@ -298,6 +298,7 @@ xfs_reinit_inode( uint64_t version = inode_peek_iversion(inode); umode_t mode = inode->i_mode; dev_t dev = inode->i_rdev; + errseq_t old_err = inode->i_mapping->wb_err; error = inode_init_always(mp->m_super, inode); @@ -306,6 +307,7 @@ xfs_reinit_inode( inode_set_iversion_queried(inode, version); inode->i_mode = mode; inode->i_rdev = dev; + inode->i_mapping->wb_err = old_err; return error; }
