linux-kernel - Re: [PATCH V5 3/4] x86/PCI: Stop enabling ECS for AMD CPUs after Fam16h

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <537FBF4F.4050406@amd.com>
Date:	Fri, 23 May 2014 16:36:15 -0500
From:	Suravee Suthikulanit <suravee.suthikulpanit@....com>
To:	Robert Richter <rric@...nel.org>,
	Bjorn Helgaas <bhelgaas@...gle.com>
CC:	Borislav Petkov <bp@...en8.de>,
	Daniel J Blueman <daniel@...ascale.com>,
	Andreas Herrmann <herrmann.der.user@...glemail.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"Aravind Gopalakrishnan" <Aravind.Gopalakrishnan@....com>,
	"linux-pci@...r.kernel.org" <linux-pci@...r.kernel.org>,
	Borislav Petkov <bp@...e.de>,
	Myron Stowe <myron.stowe@...hat.com>
Subject: Re: [PATCH V5 3/4] x86/PCI: Stop enabling ECS for AMD CPUs after
 Fam16h

On 5/23/2014 6:56 AM, Robert Richter wrote:
> On 22.05.14 20:54:54, Bjorn Helgaas wrote:
>> I'm going to go out on a limb and guess that Windows does not enable
>> ECS, so it probably uses ECAM.  Therefore, I suspect Linux's parsing
>> of MCFG is broken in some way, and we probably *could* use ECAM in all
>> these cases I'm seeing.
>
> Even if ECS is not enabled the system should be fine anyway, as ECS is
> only used to enable certain features. For family 10h this was
> originally the IBS EILVT (extended interrupt local vector table,
> needed for hw profiling) setup which need to be set by the OS which
> the BIOS didn't right. This should be fixed now and properly set by
> the BIOS on 15h+ systems.
>
> I don't remember what was added to 16h where ECS was needed, I think
> there was one (Suravee?). Not sure if this is essential.

I am not aware of anything specific in the family16h which require 
IO_ECS to be enabled.

Suravee

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/