Re: [RFC][PATCH] /proc/pid/maps doesn't match "ipcs -m" shmid

[Badari Pulavarty <pbadari@us.ibm.com>]

Eric W. Biederman wrote:

> At this point given that we actually have a small user space dependency
> and the fact that after I have reviewed the code it looks harmless to
> change the inode number of those inodes, in both cases they are just
> anonymous inodes generated with new_inode, and anything that we wrap
> is likely to be equally so.
>
> So it looks to me like we need to do three things:
> - Fix the inode number
Okay. its already done.

> - Fix the name on the hugetlbfs dentry to hold the key
I don't see need for doing this for hugetlbfs inodes. Currently, they 
don't base their
name on "key" + basing on the "key" is kind of useless anyway (its not 
unique).

> - Add a big fat comment that user space programs depend on this
>  behavior of both the dentry name and the inode number.
I don't think, the user-space can depend on the dentry-name. It can only 
depend
on inode# to match shmid. (since key is not unique esp. for key=0x00000000).

BTW, I agree that shmid is not unique even without namespaces as its 
based on
seq# and we wrap seq#.

Thanks,
Badari




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