[lkml]   [2012]   [Jun]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH] perf/x86: check ucode before disabling PEBS on SandyBridge
On Tue, Jun 12, 2012 at 01:28:55PM -0700, H. Peter Anvin wrote:
> On 06/12/2012 12:49 PM, Borislav Petkov wrote:
> >
> > Also, I'd assume we need some of the current functionality to be able to
> > load ucode without rebooting the box.
> >
> Yes, the basic idea is that we'll keep the ucode around anyway so we can
> feed it to hotplug CPUs or S3 resume. If the ucode is updated from
> userspace we'd replace the in-memory copy and load it into the CPUs.

You say CPUs, i.e. plural. What is your take on loading ucode on a
single core, i.e. the /sys/devices/system/cpu/cpuX/microcode/reload
interface? Do you guys need to load ucode only system-wide or can you
stomach per-core loads?

I want to disable it (or even remove it, modulo the whole userspace
compat blah blah) on AMD.

Also, if we do system-wide, can we have a single sysfs node where we
give the new ucode from userspace instead of per-cpu files?


Advanced Micro Devices GmbH
Einsteinring 24, 85609 Dornach
GM: Alberto Bozzo
Reg: Dornach, Landkreis Muenchen
HRB Nr. 43632 WEEE Registernr: 129 19551

 \ /
  Last update: 2012-06-13 00:04    [W:0.280 / U:0.620 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site