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From: Miklos Szeredi <mszeredi@redhat.com>
Date: Wed, 18 Jul 2018 17:46:09 +0200
Message-ID: <CAOssrKcS+kwK+S1aojhbW_4p8FJLPaafBDqDu89d=F14wT-0rw@mail.gmail.com>
Subject: Re: vfs / overlayfs conflict resolution for linux-next
To: Al Viro <viro@zeniv.linux.org.uk>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>
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On Wed, Jul 18, 2018 at 2:43 PM, Al Viro <viro@zeniv.linux.org.uk> wrote:
> On Wed, Jul 18, 2018 at 02:10:32PM +0200, Miklos Szeredi wrote:
>> On Wed, Jul 18, 2018 at 9:25 AM, Miklos Szeredi <mszeredi@redhat.com> wrote:
>> > On Wed, Jul 18, 2018 at 5:29 AM, Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>> >> Hi Al,
>> >>
>> >> On Wed, 18 Jul 2018 03:56:37 +0100 Al Viro <viro@ZenIV.linux.org.uk> wrote:
>> >>>
>> >>> ... and now it even builds.  Said that, I would really like to hear something
>> >>> from you - I can duplicate the entire overlayfs-next and merge it into
>> >>> my #for-next and ask Steven to use that instead of your tree, but I very
>> >>> much dislike going over your head like that.
>> >>>
>> >>> I realize that you'd been away for a while and probably are digging yourself
>> >>> from under the piles of mail, but it's getting late in the cycle and I want
>> >>> to get #for-next into reasonably sane shape.  Please, look through that
>> >>> thing and respond.

Pushed updated series based on your vfs.git#for-ovl branch to the
overlayfs-next tree.  There's the additional patch dealing with
nr_files accounting (will post for review shortly).  That one has a
trivial conflict with the mount series, otherwise merges cleanly with
viro/vfs.git#for-next.

I like the call_with_creds() idea.  I didn't realize that
override_creds()/revert_creds() can be quite heavyweight due to doing
(unnecessary in this case) refcounting.   Could use call_with_creds()
in overlayfs too, since we hold ref on ofs->creator_cred for the
lifetime of the filesystem.

Thanks,
Miklos