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Date: Mon, 02 Mar 2026 20:19:24 +0100
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Cc: "Greg Kroah-Hartman" <gregkh@linuxfoundation.org>, "Rafael J. Wysocki"
 <rafael@kernel.org>, "Saravana Kannan" <saravanak@kernel.org>, "Andrew
 Morton" <akpm@linux-foundation.org>, <driver-core@lists.linux.dev>,
 <rust-for-linux@vger.kernel.org>, <linux-kernel@vger.kernel.org>
To: "Linus Torvalds" <torvalds@linux-foundation.org>
From: "Danilo Krummrich" <dakr@kernel.org>
Subject: Re: [GIT PULL] Driver core changes for 7.0-rc1
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On Sun Mar 1, 2026 at 10:01 PM CET, Linus Torvalds wrote:
> So the thing that would matter is the longest actual real driver name.
> Aren't those typically just a few bytes (eg "regulator-bus-drv" or
> "__typec_altmode_driver" being long ones I find with a bad grep
> pattern that might miss millions of other cases)

Yes, generally they should be pretty short.

OOC, I asked an LLM to figure it out (so take this with the necessary grain=
 of
salt):

	Out of ~7,560 unique driver names:
=09
	=E2=94=8C=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=
=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=AC=E2=94=80=E2=94=80=E2=
=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=
=80=E2=94=90
	=E2=94=82 Threshold  =E2=94=82   Count   =E2=94=82
	=E2=94=9C=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=
=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=BC=E2=94=80=E2=94=80=E2=
=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=
=80=E2=94=A4
	=E2=94=82 > 32 chars =E2=94=82 6 (0.08%) =E2=94=82
	=E2=94=9C=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=
=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=BC=E2=94=80=E2=94=80=E2=
=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=
=80=E2=94=A4
	=E2=94=82 > 48 chars =E2=94=82 1 (0.01%) =E2=94=82
	=E2=94=9C=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=
=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=BC=E2=94=80=E2=94=80=E2=
=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=
=80=E2=94=A4
	=E2=94=82 > 64 chars =E2=94=82 0         =E2=94=82
	=E2=94=94=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=
=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=B4=E2=94=80=E2=94=80=E2=
=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=80=E2=94=
=80=E2=94=98
=09
	Length distribution
=09
	 1-10 chars:  3,513  (46.5%)
	11-16 chars:  3,111  (41.1%)
	17-24 chars:    880  (11.6%)
	25-32 chars:     50  ( 0.7%)
	33-49 chars:      6  ( 0.1%)

> IOW, it looks like it would be fine to just say "use just a 32-byte
> buffer" if a buffer is needed.

Assuming the above is roughly correct, you are pretty close. :)

> Of course, if no buffer is needed that's even better.

Yes, I don't think we ever need to obtain a copy other than through
sysfs_emit().