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Date: Thu, 26 Oct 2017 12:54:30 +0200
From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com>,
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Subject: Re: [PATCH v2] tpm: use struct tpm_chip for tpm_chip_find_get()
Message-ID: <20171026105430.t6khk6cekk3cyfrs@linux.intel.com>
References: <20171025115508.5682-1-jarkko.sakkinen@linux.intel.com>
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On Wed, Oct 25, 2017 at 02:17:44PM -0600, Jason Gunthorpe wrote:
> On Wed, Oct 25, 2017 at 10:07:46PM +0200, Jarkko Sakkinen wrote:
> 
> > The id has a nice feature that it is unique for one boot cycle you can
> > even try to get a chip that has been deleted. It has the most stable
> > properties in the long run.
> 
> It isn't unique, we can re-use ids them via idr_alloc(). We should
> never use index inside the kernel.
> 
> > Address is a reusable identifier in one boot cycle.
> 
> It is invalid to pass in a chip for which the caller does not hold a
> kref, so address is the safest argument.
> 
> Jason

I'll buy this too (sending update today).

/Jarkko