From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 66AC32D041 for ; Thu, 4 Jan 2024 23:27:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="EwTyb+0f" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 32F86C433C7; Thu, 4 Jan 2024 23:27:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1704410868; bh=M1aJpbtpXgUyoqu9ulrBIpx47ZVuML+XInKcwKzDSNM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=EwTyb+0fcCdbrA2M9WFFJyD+MZ1/N3wGC4bxvJrE62ZLxOxj+SuJI2ASjabtSdB0a 6iqw6cM1742yVWqQOl+fDS3B6qqKLxRIw7puclH1a4Re+HTLcW2uvy25rEZrksK+mD X7XAzW9WUK/dosmpb6oQuh+E/euF1pbeS6xQSpWB5DL/k4Hfw8vJ6siHW24wsyIer6 ceT8Ib+RiaGzCqBJwBssjbVk3Yy1Jadb1b8Z41jC0AiH1CiLv4jN5t8Ut05PQ15gWr gI9K0UDAs8qmoWM0lFhq/cqHuQaVFQldV2JY745KvhXiUYiDa9OZLvfDYIgxhyc48h 2zZTvjfDitpqQ== Date: Fri, 5 Jan 2024 00:27:45 +0100 From: Alejandro Colomar To: =?utf-8?B?0L3QsNCx?= Cc: linux-man@vger.kernel.org Subject: Re: [PATCH] cpuid.4: note which CPUs don't support CPUID and what happens Message-ID: References: Precedence: bulk X-Mailing-List: linux-man@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="i9D+2SDtb6ssw6LG" Content-Disposition: inline In-Reply-To: --i9D+2SDtb6ssw6LG Content-Type: text/plain; protected-headers=v1; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Date: Fri, 5 Jan 2024 00:27:45 +0100 From: Alejandro Colomar To: =?utf-8?B?0L3QsNCx?= Cc: linux-man@vger.kernel.org Subject: Re: [PATCH] cpuid.4: note which CPUs don't support CPUID and what happens Hi, On Thu, Jan 04, 2024 at 11:31:21PM +0100, =D0=BD=D0=B0=D0=B1 wrote: > "Early 486" comes from an uncited wikipedia table, added in > https://en.wikipedia.org/w/index.php?title=3DCPUID&diff=3Dprev&oldid=3D= 592047209 > https://en.wikipedia.org/w/index.php?title=3DCPUID&diff=3Dprev&oldid=3D= 592047978 > but I spot-checked the rest of the table accurate to CPUs in my house > (the oldest of which is an original Celeron, so no 486), > and "early 486" is better than "early x86" which can mean anything. >=20 > This does leave earlier x86 unmentioned, > but Linux hasn't targeted those in over a decade, > so they're out of scope anyway. >=20 > Signed-off-by: Ahelenia Ziemia=C5=84ska Patch applied. Thanks! Have a lovely day, Alex > --- > man4/cpuid.4 | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) >=20 > diff --git a/man4/cpuid.4 b/man4/cpuid.4 > index bd883e6d3..0b38fabe3 100644 > --- a/man4/cpuid.4 > +++ b/man4/cpuid.4 > @@ -69,7 +69,9 @@ .SH NOTES > There is no support for CPUID functions that require additional > input registers. > .P > -Very old x86 CPUs don't support CPUID. > +Early i486 CPUs do not support the CPUID instruction; > +.\" arch/x86/kernel/cpuid.c cpuid_open() > +opening this device for those CPUs fails with EIO. > .SH SEE ALSO > .BR cpuid (1) > .P > --=20 > 2.39.2 --=20 Looking for a remote C programming job at the moment. --i9D+2SDtb6ssw6LG Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEE6jqH8KTroDDkXfJAnowa+77/2zIFAmWXPvEACgkQnowa+77/ 2zKpUw/+JUfZ+9wE1SXn3h/8UYPU5mAoOkDLWgXrUPDswCpUdbq932cwiwFMfYK8 N6B0ILcBUOfIgAsQlzOg2yFhGQlp1UNUGyPmnUOo4AvNpM8OMxiLFegLTJ1c40De dU/MT4xc56h5kcXGM3QX4s47j5KrHIkGUA0u9hB4nmK4LAhpkIjoX5MpHnO5GBdt FXqcbNfrvxNQuaumVMJ+ygayFCz32fvpovdJf4FLNAObpC9ueLRnRND5fe7tKGsA MZDr05uMgH5aqoT8TschdUokTFO2UGGDfKPIRhdhpZG0u8EMvTUjwR7D22s0FQ3p x90UoyR76kXfky+FFOucZ4559HPY4ykB2p6dK/59DCO8p2zKVM/nRCJdPqHHPemf vGvyVx/28Iv+lJTJcEdXpQfsS6/a3C3nHFiOFMMYiggws6I2b363kJdy0W6pJyrX gWxhzliQg5NJGUKsC6FfIMb6ylS4P0Hn3IVcQcz/+b6ZBRFRm2CfcQkNGzDaMC+B XVixdEO1TqX7GrBqNa7ACjQ5ZJXWM1Gfen83OJQUafgSlJ9IthlrMrX0P+Kwr29Y H3mziNr4tE33VuvMw6gJooP1pj52ID6oMeeA6777qqI1DAYMmY0qoTKlFtgUphMn eKDBlLy800Gf4xxEH2uKKVTH8NqBY+IXqDVEba+fVZ/hkzj5G+o= =XXt/ -----END PGP SIGNATURE----- --i9D+2SDtb6ssw6LG--