Re: PROBLEM: Mounting multiple lowerdirs with "lowerdir=/tmp/a0,/tmp/a" returns 32

[hujianyang <hujianyang@huawei.com>]

Hi Fabian,

Thanks for reporting.

On 2015/1/13 5:59, Fabian Sturm wrote:
> 
> sudo mount -t overlay -o lowerdir=/tmp/a,/tmp/a0 overlay /tmp/merged

I think the cause of this failure is the wrong mount option you
are using.

should be:

sudo mount -t overlay -o lowerdir=/tmp/a:/tmp/a0 overlay /tmp/merged

Comma is used to separate different mount options. Overlayfs use
colon as the separator between lower directories.

I don't know if it is a correct resolution for your problem. You
can try it first. It's OK in my environment to mount ovl with
numbers in directory name.

> ret=$(echo $?)
> echo $ret
> if [[ "$ret" == "0" ]]; then
>     sudo umount /tmp/merged
> fi
> 
> sudo mount -t overlay -o lowerdir=/tmp/a,/tmp/0a overlay /tmp/merged
> ret=$(echo $?)
> echo $ret
> if [[ "$ret" == "0" ]]; then
>     sudo umount /tmp/merged
> fi
> 

Anyway, I think overlayfs should print an error message if an
incorrect mount option is caught like other filesystems.


Reported-by: Fabian Sturm <fabian.sturm@aduu.de>
Signed-off-by: hujianyang <hujianyang@huawei.com>
---
 fs/overlayfs/super.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index b90952f..ab3c8cb 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -615,6 +615,7 @@ static int ovl_parse_opt(char *opt, struct ovl_config *config)
 			break;

 		default:
+			pr_err("overlayfs: unrecognized mount option \"%s\" or missing value\n", p);
 			return -EINVAL;
 		}
 	}
-- 
1.6.0.2