Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752890Ab2FLPNX (ORCPT ); Tue, 12 Jun 2012 11:13:23 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:52087 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752335Ab2FLPNW (ORCPT ); Tue, 12 Jun 2012 11:13:22 -0400 Message-ID: <4FD75C84.7020105@canonical.com> Date: Tue, 12 Jun 2012 17:13:08 +0200 From: Stefan Bader User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:12.0) Gecko/20120430 Thunderbird/12.0.1 MIME-Version: 1.0 To: Mahmood Naderan CC: Borislav Petkov , "linux-kernel@vger.kernel.org" , Andreas Herrmann Subject: Re: CPU MTRRs and linux kernel References: <1339493860.10145.YahooMailNeo@web111708.mail.gq1.yahoo.com> <20120612103954.GB10124@x1.osrc.amd.com> <1339508890.39685.YahooMailNeo@web111705.mail.gq1.yahoo.com> In-Reply-To: <1339508890.39685.YahooMailNeo@web111705.mail.gq1.yahoo.com> X-Enigmail-Version: 1.5pre Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="------------enig68729D020F2947AB403F2414" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4724 Lines: 126 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig68729D020F2947AB403F2414 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 12.06.2012 15:48, Mahmood Naderan wrote: > Thanks Borislav, > I want to know, should I upgrade to the latest kernel or it is possible= to download the source of 2.6.32-24 from repository and modify cleanup.c= and then recompile? >=20 Just update to the latest kernel. 2.6.32-24.39 is way old. The fix Boris mentioned was in 2.6.32-27.49. And the latest kernel is 2.6.32-41.89 by n= ow... -Stefan > ~MN >=20 > ----- Original Message ----- > From: Borislav Petkov > To: Mahmood Naderan > Cc: "linux-kernel@vger.kernel.org" ; Andr= eas Herrmann > Sent: Tuesday, June 12, 2012 3:09 PM > Subject: Re: CPU MTRRs and linux kernel >=20 > On Tue, Jun 12, 2012 at 02:37:40AM -0700, Mahmood Naderan wrote: >> Hi everybody, >> Abour rhis warnning in boot log: >> >> WARNING: BIOS bug: CPU MTRRs don't cover all of memory, losing 61952MB= of RAM >> >> =20 >> I >> searched a lot however didn't find a clear solution. Does AMD new=20 >> processors (62XX) have problems with new kernels or old kernels?? >> Mine is: >> >> Linux n1 2.6.32-24-server #39-Ubuntu SMP Wed Jul 28 06:21:40 UTC 2010 = x86_64 GNU/Linux >> >> Should I upgrade? >=20 > Yes, fix is below and it got backported to -stable AFAICT but obviously= > the ubuntus don't have it in the kernel you cite above. >=20 >=20 > commit 3fdbf004c1706480a7c7fac3c9d836fa6df20d7d > Author: Andreas Herrmann > Date: Thu Sep 30 14:32:35 2010 +0200 >=20 > x86, mtrr: Assume SYS_CFG[Tom2ForceMemTypeWB] exists on all future = AMD CPUs > =20 > Instead of adapting the CPU family check in amd_special_default_mtr= r() > for each new CPU family assume that all new AMD CPUs support the > necessary bits in SYS_CFG MSR. > =20 > Tom2Enabled is architectural (defined in APM Vol.2). > Tom2ForceMemTypeWB is defined in all BKDGs starting with K8 NPT. > In pre K8-NPT BKDG this bit is reserved (read as zero). > =20 > W/o this adaption Linux would unnecessarily complain about bad MTRR= > settings on every new AMD CPU family, e.g. > =20 > [ 0.000000] WARNING: BIOS bug: CPU MTRRs don't cover all of memo= ry, losing 4863MB of RAM. > =20 > Cc: stable@kernel.org # .32.x, .35.x > Signed-off-by: Andreas Herrmann > LKML-Reference: <20100930123235.GB20545@loge.amd.com> > Signed-off-by: H. Peter Anvin >=20 > diff --git a/arch/x86/kernel/cpu/mtrr/cleanup.c b/arch/x86/kernel/cpu/m= trr/cleanup.c > index c5f59d071425..ac140c7be396 100644 > --- a/arch/x86/kernel/cpu/mtrr/cleanup.c > +++ b/arch/x86/kernel/cpu/mtrr/cleanup.c > @@ -827,7 +827,7 @@ int __init amd_special_default_mtrr(void) >=20 > if (boot_cpu_data.x86_vendor !=3D X86_VENDOR_AMD) > return 0; > - if (boot_cpu_data.x86 < 0xf || boot_cpu_data.x86 > 0x11) > + if (boot_cpu_data.x86 < 0xf) > return 0; > /* In case some hypervisor doesn't pass SYSCFG through: */ > if (rdmsr_safe(MSR_K8_SYSCFG, &l, &h) < 0) >=20 --------------enig68729D020F2947AB403F2414 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBCgAGBQJP11yMAAoJEOhnXe7L7s6jZwQP/241DaN5bhzxYS4dhtIR5dCh vZkpw7WPTc4omil/p+avwT7UYaTj2nVxPc9HDcdlYoJF/uBQG1J1pIIYZCQwNynT FaVMGuWpoxPlJ9hdN2k5hNQs1bWIg3g+HfYeRWuezvR31zzIfpkv6zXZ2I1ha3p1 bvTJOscMXoR+J/VSl1tCLYwUeThtDZdQLcsHjH1bMBiX6+3bmTUVTa8CZZd8pR05 p9Bbeb1A1bx7JoLgxaY6DIZwktiFi7c4hkVSHhOgEg8DT61RtlWe0oauyXSazufy P1qqOcFOH13/WKxb3HvxnNPvogAOihcG9PYnyny3SKow5y5HEH0/yfTYIj0iQxKd bGEDYIFmTwv3CeKFDnzziR++8rDuCscDzQ1QmVM1VnqSPfipdWpg3zRUTpwo0KP+ N+WkrcygbCAaOMDgIZlfKNV4ZggX/XJZJnWL1QQkWALRC3QvPZ3pHSUhbntcglrl W1cpy4mFpklvJHnh61cv9m8UW/Gk8+123rRd+sW0450bakopnTgtsGBtkoeUOV5f jqxJkg0qqmnsI9JUpJvnI909D6ixCZt/NdJKTkon4GqeBl4mBzJeoQQeZPHe4C6E cJLX880lSe7QNrZ9e1pV8YMG8eYSIlMd2dyLXMXB2VHqAwzN+qv6h40HS2K/dah5 DrWMreJSCJjlmVWj7ERl =+Sog -----END PGP SIGNATURE----- --------------enig68729D020F2947AB403F2414-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/