Bug 209487

Summary: mounting (ext3) filesystems twice
Product: [Fedora] Fedora Reporter: Florian La Roche <laroche>
Component: kernelAssignee: Eric Sandeen <esandeen>
Status: CLOSED NOTABUG QA Contact: Brian Brock <bbrock>
Severity: medium Docs Contact:
Priority: medium    
Version: rawhideCC: kzak, wtogami
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OS: Linux   
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Last Closed: 2006-10-05 19:43:09 UTC Type: ---
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Description Florian La Roche 2006-10-05 16:03:43 UTC
Description of problem:

With a current FC-development machine, I can mount a ext3 filesystem
read-write twice without getting any warning or error message from the
kernel:

    mount /dev/sda1 /data1
    mount /dev/sda1 /data2


Is this check up to the (l)user requesting this or should the kernel
return EBUSY for this case?

regards,

Florian La Roche





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Comment 1 Karel Zak 2006-10-05 16:13:41 UTC
Same with 2.6.17-1.2187_FC5

Comment 2 Eric Sandeen 2006-10-05 19:43:09 UTC
So does 2.6.9...

[root@aluminium ~]# mount /dev/hda7 /mnt/test
[root@aluminium ~]# mount /dev/hda7 /mnt/test2

[root@aluminium ~]# uname -a
Linux aluminium.msp.redhat.com 2.6.9-42.EL #1 Wed Jul 12 23:16:43 EDT 2006 i686
i686 i386 GNU/Linux

[root@aluminium ~]# mount | grep hda7
/dev/hda7 on /mnt/test type ext3 (rw)
/dev/hda7 on /mnt/test2 type ext3 (rw)

And it can be done with any other fileystem too.

but there's nothing wrong with that... why do you think this is a bug?

Comment 3 Karel Zak 2006-10-05 20:38:59 UTC
Sorry, you're right. I've to refresh my old knowledge of linux. It's possible
since 2.4. The mount(2) man page:

 Since Linux 2.4 a single filesystem can be visible at  multiple  mount  points,
 and multiple mounts can be stacked on the same mount point.