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Date: Tue, 30 Jan 2024 16:23:02 -0800
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Brian Norris <briannorris@chromium.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	=?iso-8859-1?Q?N=EDcolas_F=2E_R=2E_A=2E?= Prado <nfraprado@collabora.com>,
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Subject: Re: [PATCH v2 2/7] firmware: coreboot: Generate aliases for coreboot
 modules
Message-ID: <2024013012-gully-goofy-2a55@gregkh>
References: <20240112131857.900734-1-nfraprado@collabora.com>
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 <ZaQVScQ2AYquG-Zr@smile.fi.intel.com>
 <ZbA4VthTMPT7BSRo@google.com>
 <2024013059-poison-equation-81d1@gregkh>
 <CA+ASDXM-m6U+JFvBSSHMxAf8Ct-T-pL8tmcHxHQjepdRFR-s1w@mail.gmail.com>
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On Tue, Jan 30, 2024 at 04:01:57PM -0800, Brian Norris wrote:
> On Tue, Jan 30, 2024 at 3:51 PM Greg Kroah-Hartman
> <gregkh@linuxfoundation.org> wrote:
> > On Tue, Jan 23, 2024 at 02:06:14PM -0800, Brian Norris wrote:
> > > "Don't you want to have a driver data or so associated with this?"
> ...
> > But why limit yourself to 32bits now?  Why not make it 64?  It is going
> > to be sent to userspace, so you have to be very careful about it.
> 
> Is that question related to the question I pasted/replied to, about
> driver data? Or a new topic? Sorry if I'm misunderstanding.

Same question, driver data, you make it 32 bits.

> Anyway, for the size of the tag field: I don't have a strong opinion.
> But FWIW, they're coming from this project:
> 
> https://review.coreboot.org/plugins/gitiles/coreboot/+/269b23280f928510bcadd23182294e5b9dad11ec/payloads/libpayload/include/coreboot_tables.h#36
> 
> As you can see there, we're extremely far from exhausting 16 bits, let alone 32.

We've run into running out of bits in other subsystems before, it's
"free" now, just be safe and make it 64 like I think Andy is suggesting.

thanks,

greg k-h