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Date:   Wed, 29 Apr 2020 14:57:26 +0200
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Luis Chamberlain <mcgrof@kernel.org>
Cc:     Christoph Hellwig <hch@infradead.org>, axboe@kernel.dk,
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        Michal Hocko <mhocko@kernel.org>,
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Subject: Re: [PATCH v3 4/6] blktrace: fix debugfs use after free
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On Wed, Apr 29, 2020 at 12:21:52PM +0000, Luis Chamberlain wrote:
> On Wed, Apr 29, 2020 at 05:04:06AM -0700, Christoph Hellwig wrote:
> > On Wed, Apr 29, 2020 at 12:02:30PM +0000, Luis Chamberlain wrote:
> > > > Err, that function is static and has two callers.
> > > 
> > > Yes but that is to make it easier to look for who is creating the
> > > debugfs_dir for either the request_queue or partition. I'll export
> > > blk_debugfs_root and we'll open code all this.
> > 
> > No, please not.  exported variables are usually a bad idea.  Just
> > skip the somewhat pointless trivial static function.
> 
> Alrighty. It has me thinking we might want to only export those symbols
> to a specific namespace. Thoughts, preferences?
> 
> BLOCK_GENHD_PRIVATE ?

That's a nice add-on issue after this is fixed.  As Christoph and I
pointed out, you have _less_ code in the file if you remove the static
wrapper function.  Do that now and then worry about symbol namespaces
please.

thanks,

greg k-h