4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: NeilBrown <neilb@xxxxxxxx> commit 065e519e71b2c1f41936cce75b46b5ab34adb588 upstream. if called md_set_readonly and set MD_CLOSING bit, the mddev cannot be opened any more due to the MD_CLOING bit wasn't cleared. Thus it needs to be cleared in md_ioctl after any call to md_set_readonly() or do_md_stop(). Signed-off-by: NeilBrown <neilb@xxxxxxxx> Fixes: af8d8e6f0315 ("md: changes for MD_STILL_CLOSED flag") Signed-off-by: Zhilong Liu <zlliu@xxxxxxxx> Signed-off-by: Shaohua Li <shli@xxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/md/md.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -6752,6 +6752,7 @@ static int md_ioctl(struct block_device void __user *argp = (void __user *)arg; struct mddev *mddev = NULL; int ro; + bool did_set_md_closing = false; if (!md_ioctl_valid(cmd)) return -ENOTTY; @@ -6841,7 +6842,9 @@ static int md_ioctl(struct block_device err = -EBUSY; goto out; } + WARN_ON_ONCE(test_bit(MD_CLOSING, &mddev->flags)); set_bit(MD_CLOSING, &mddev->flags); + did_set_md_closing = true; mutex_unlock(&mddev->open_mutex); sync_blockdev(bdev); } @@ -7041,6 +7044,8 @@ unlock: mddev->hold_active = 0; mddev_unlock(mddev); out: + if(did_set_md_closing) + clear_bit(MD_CLOSING, &mddev->flags); return err; } #ifdef CONFIG_COMPAT