Re: Does ceph_fill_inode() mishandle I_NEW?

[David Howells]

slava@xxxxxxxxxxx wrote:

> What do you mean by mishandling? Do you imply that Ceph has to set up
> the I_NEW somehow? Is it not VFS responsibility?

No - I mean that if I_NEW *isn't* set when the function is called,
ceph_fill_inode() will go and partially reinitialise the inode.  Now, having
reviewed the code in more depth and talked to Jeff Layton about it, I think
that the non-I_NEW pass will only change pointers with some sort of locking
and will release the old target - though it may overwrite some pointers with
the same value without protection (i_fops for example).

That said, if it's possible for *two* processes to be going through that
function without I_NEW set, you can get places where both of them will try
freeing the old data and replacing it with new without any locking - but I
don't know if that can happen.

David