On Tue, Mar 15, 2016 at 04:12:14PM +0800, Eryu Guan wrote:

quoted

This is a test that performs simple I/O on dm error device, which
returns EIO on all I/O request.

This is motivated by an ext4 bug that crashes kernel on error path when
trying to update atime. Following kernel patch should fix the issue

  ext4: fix NULL pointer dereference in ext4_mark_inode_dirty()

Signed-off-by: Eryu Guan <redacted>
---

Fails with:

@@ -1,2 +1,6 @@
 QA output created by 338
  Silence is golden
  +specified blocksize 1024 is less than device physical sector size 4096
  +switching to logical sector size 512
  +mkfs.xfs: /dev/mapper/error-test appears to contain an existing filesystem (xfs).
  +mkfs.xfs: Use the -f option to force overwrite.

And then it failed to clean up properly and caused all sorts of
subsequent problems.