From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Howells <dhowells@redhat.com>
Subject: Re: Can ovl_drop_write() be called earlier in ovl_dentry_open()
Date: Mon, 01 Jun 2015 16:45:03 +0100
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To: Miklos Szeredi <miklos@szeredi.hu>
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Miklos Szeredi <miklos@szeredi.hu> wrote:

> > In ovl_dentry_open(), ovl_drop_write() is called after vfs_open() - but is
> > this actually necessary?  Can't we just drop it post-copyup?  After all,
> > that's all we wanted the write lock for, right?
> 
> Hmm,  that could result in a race where remount r/o of upper fs comes
> in between copy-up and vfs_open() so copy-up succeeds but the actual
> open fails.  It's harmless, though, and not  very likely.  So I guess
> your patch is OK.

That race is there anyway if there's no copy up, right?

David