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Old 01-17-2011, 05:10 PM
BRM
 
Default Microcode update AMD

----- Original Message ----

> I have two questions:
>
> 1) Do I have to enable microcode updates in the BIOS of my Crosshair
> IV Formula to activate microcodes push in the CPU by the module
> "microcode" ? (AMD Phenom X6 1090T)

Not sure about BIOS, but the Linux Kernel you are running will certainly need
support enabled too.

> 2) Does anyone know, what these microcodes do? They are fixes for...
> ...what?

The Intel and AMD processors are more abstract than physical now. With i486 and
earlier the processors were typically hard wired; hardware "bug" fixes could not
be pushed out.
Intel's Pentium (and I don't know which AMD) started using micro-code to program
the processor. This enabled them to push out "hardware" bug fixes for the
processors.

So what happens is the x86 instruction (e.g. mov ax, bx) gets translated to
micro-code first, then it gets processed, and the result translated back to the
expected instruction result - essentially, emulating the x86 instruction set in
the processor. That's the simple version.

So now when they discover a bug in the hardware they can push out a micro-code
update to either fix the "hardware" (microcode) bug or work around a hardware
(physical hardware) bug.

Ben
 
Old 01-17-2011, 05:34 PM
 
Default Microcode update AMD

BRM <bm_witness@yahoo.com> [11-01-17 19:16]:
> ----- Original Message ----
>
> > I have two questions:
> >
> > 1) Do I have to enable microcode updates in the BIOS of my Crosshair
> > IV Formula to activate microcodes push in the CPU by the module
> > "microcode" ? (AMD Phenom X6 1090T)
>
> Not sure about BIOS, but the Linux Kernel you are running will certainly need
> support enabled too.
>
> > 2) Does anyone know, what these microcodes do? They are fixes for...
> > ...what?
>
> The Intel and AMD processors are more abstract than physical now. With i486 and
> earlier the processors were typically hard wired; hardware "bug" fixes could not
> be pushed out.
> Intel's Pentium (and I don't know which AMD) started using micro-code to program
> the processor. This enabled them to push out "hardware" bug fixes for the
> processors.
>
> So what happens is the x86 instruction (e.g. mov ax, bx) gets translated to
> micro-code first, then it gets processed, and the result translated back to the
> expected instruction result - essentially, emulating the x86 instruction set in
> the processor. That's the simple version.
>
> So now when they discover a bug in the hardware they can push out a micro-code
> update to either fix the "hardware" (microcode) bug or work around a hardware
> (physical hardware) bug.
>
> Ben
>
>

Hi Ben,

thanks for your explanation...
I meant: What is fixed the uc-patches? Does "mov" only except "17" as
argument...or...
I searched AMD for a changelog or something like but I ound nothing...

Best regards,
mcc
 
Old 01-17-2011, 05:48 PM
Mark Knecht
 
Default Microcode update AMD

On Mon, Jan 17, 2011 at 10:10 AM, BRM <bm_witness@yahoo.com> wrote:
> ----- Original Message ----
>
>> I have two questions:
>>
>> *1) Do I have to enable microcode *updates in the BIOS of my Crosshair
>> * * IV Formula to activate *microcodes push in the CPU by the module
>> * * "microcode" ? (AMD *Phenom X6 1090T)
>
> Not sure about BIOS, but the Linux Kernel you are running will certainly need
> support enabled too.
>
>> *2) Does anyone know, what these microcodes do? They are *fixes for...
>> * * ...what?
>
> The Intel and AMD processors are more abstract than physical now. With i486 and
> earlier the processors were typically hard wired; hardware "bug" fixes could not
> be pushed out.
> Intel's Pentium (and I don't know which AMD) started using micro-code to program
> the processor. This enabled them to push out "hardware" bug fixes for the
> processors.
>
> So what happens is the x86 instruction (e.g. mov ax, bx) gets translated to
> micro-code first, then it gets processed, and the result translated back to the
> expected instruction result - essentially, emulating the x86 instruction set in
> the processor. That's the simple version.
>
> So now when they discover a bug in the hardware they can push out a micro-code
> update to either fix the "hardware" *(microcode) bug or work around a hardware
> (physical hardware) bug.
>
> Ben

Ben,
Do you know how security on these updates is handled? Seems to me
this is an area rife for exploitation so I've been very hesitant to
use them until I understood more.

Cheers,
Mark
 
Old 01-17-2011, 06:08 PM
Volker Armin Hemmann
 
Default Microcode update AMD

On Monday 17 January 2011 18:21:48 meino.cramer@gmx.de wrote:
> Hi,
>
> I have two questions:
>
> 1) Do I have to enable microcode updates in the BIOS of my Crosshair
> IV Formula to activate microcodes push in the CPU by the module
> "microcode" ? (AMD Phenom X6 1090T)
>

you ALWAYS have to activate that! This way the bios updates the microcode with
the latest version it is carrying around. Not activating that option is
really, really stupid. For many reasons. It is also (almost) completely
unrelated to that blob.

That blob is for the OS so you can upload an even more recent version of
microcode. In case your bios sucks. For example.

> 2) Does anyone know, what these microcodes do? They are fixes for...
> ...what?

the CPU. All CPUs use microcode. For decades. Google, or go straight to
wikipedia.
http://en.wikipedia.org/wiki/Microcode
 
Old 01-17-2011, 06:12 PM
Volker Armin Hemmann
 
Default Microcode update AMD

On Monday 17 January 2011 10:48:36 Mark Knecht wrote:
> On Mon, Jan 17, 2011 at 10:10 AM, BRM <bm_witness@yahoo.com> wrote:
> > ----- Original Message ----
> >
> >> I have two questions:
> >>
> >> 1) Do I have to enable microcode updates in the BIOS of my Crosshair
> >> IV Formula to activate microcodes push in the CPU by the module
> >> "microcode" ? (AMD Phenom X6 1090T)
> >
> > Not sure about BIOS, but the Linux Kernel you are running will certainly
> > need support enabled too.
> >
> >> 2) Does anyone know, what these microcodes do? They are fixes for...
> >> ...what?
> >
> > The Intel and AMD processors are more abstract than physical now. With
> > i486 and earlier the processors were typically hard wired; hardware
> > "bug" fixes could not be pushed out.
> > Intel's Pentium (and I don't know which AMD) started using micro-code to
> > program the processor. This enabled them to push out "hardware" bug
> > fixes for the processors.
> >
> > So what happens is the x86 instruction (e.g. mov ax, bx) gets translated
> > to micro-code first, then it gets processed, and the result translated
> > back to the expected instruction result - essentially, emulating the
> > x86 instruction set in the processor. That's the simple version.
> >
> > So now when they discover a bug in the hardware they can push out a
> > micro-code update to either fix the "hardware" (microcode) bug or work
> > around a hardware (physical hardware) bug.
> >
> > Ben
>
> Ben,
> Do you know how security on these updates is handled? Seems to me
> this is an area rife for exploitation so I've been very hesitant to
> use them until I understood more.

you can not not use them because alsmost all bios load the microcode
automatically.
 
Old 01-17-2011, 06:14 PM
Volker Armin Hemmann
 
Default Microcode update AMD

On Monday 17 January 2011 19:34:08 meino.cramer@gmx.de wrote:
> BRM <bm_witness@yahoo.com> [11-01-17 19:16]:
> > ----- Original Message ----
> >
> > > I have two questions:
> > > 1) Do I have to enable microcode updates in the BIOS of my
> > > Crosshair
> > >
> > > IV Formula to activate microcodes push in the CPU by the
> > > module
> > > "microcode" ? (AMD Phenom X6 1090T)
> >
> > Not sure about BIOS, but the Linux Kernel you are running will certainly
> > need support enabled too.
> >
> > > 2) Does anyone know, what these microcodes do? They are fixes
> > > for...
> > >
> > > ...what?
> >
> > The Intel and AMD processors are more abstract than physical now. With
> > i486 and earlier the processors were typically hard wired; hardware
> > "bug" fixes could not be pushed out.

even the 68000 used microcode...

> > Intel's Pentium (and I don't know which AMD) started using micro-code to
> > program the processor. This enabled them to push out "hardware" bug
> > fixes for the processors

sure that microcode was not introduced to x86 a lot earlier?

> >
> > So what happens is the x86 instruction (e.g. mov ax, bx) gets translated
> > to micro-code first, then it gets processed, and the result translated
> > back to the expected instruction result - essentially, emulating the
> > x86 instruction set in the processor. That's the simple version.
> >
> > So now when they discover a bug in the hardware they can push out a
> > micro-code update to either fix the "hardware" (microcode) bug or work
> > around a hardware (physical hardware) bug.
> >
> > Ben
>
> Hi Ben,
>
> thanks for your explanation...
> I meant: What is fixed the uc-patches? Does "mov" only except "17" as
> argument...or...
> I searched AMD for a changelog or something like but I ound nothing...

they never publish changelogs for microcode.
 
Old 01-17-2011, 06:19 PM
 
Default Microcode update AMD

Volker Armin Hemmann <volkerarmin@googlemail.com> [11-01-17 20:16]:
> On Monday 17 January 2011 18:21:48 meino.cramer@gmx.de wrote:
> > Hi,
> >
> > I have two questions:
> >
> > 1) Do I have to enable microcode updates in the BIOS of my Crosshair
> > IV Formula to activate microcodes push in the CPU by the module
> > "microcode" ? (AMD Phenom X6 1090T)
> >
>
> you ALWAYS have to activate that! This way the bios updates the microcode with
> the latest version it is carrying around. Not activating that option is
> really, really stupid. For many reasons. It is also (almost) completely
> unrelated to that blob.
>
> That blob is for the OS so you can upload an even more recent version of
> microcode. In case your bios sucks. For example.
>
> > 2) Does anyone know, what these microcodes do? They are fixes for...
> > ...what?
>
> the CPU. All CPUs use microcode. For decades. Google, or go straight to
> wikipedia.
> http://en.wikipedia.org/wiki/Microcode
>

Cool down. I know for waht microcodes are good for.

My question means: What specific bugs/features of my CPU get fixed,
when I use the microcde included in the recent microcode update???
 
Old 01-17-2011, 06:46 PM
Volker Armin Hemmann
 
Default Microcode update AMD

On Monday 17 January 2011 20:19:04 meino.cramer@gmx.de wrote:
> Volker Armin Hemmann <volkerarmin@googlemail.com> [11-01-17 20:16]:
> > On Monday 17 January 2011 18:21:48 meino.cramer@gmx.de wrote:
> > > Hi,
> > >
> > > I have two questions:
> > > 1) Do I have to enable microcode updates in the BIOS of my
> > > Crosshair
> > >
> > > IV Formula to activate microcodes push in the CPU by the
> > > module
> > > "microcode" ? (AMD Phenom X6 1090T)
> >
> > you ALWAYS have to activate that! This way the bios updates the
> > microcode with the latest version it is carrying around. Not activating
> > that option is really, really stupid. For many reasons. It is also
> > (almost) completely unrelated to that blob.
> >
> > That blob is for the OS so you can upload an even more recent version of
> > microcode. In case your bios sucks. For example.
> >
> > > 2) Does anyone know, what these microcodes do? They are fixes
> > > for...
> > >
> > > ...what?
> >
> > the CPU. All CPUs use microcode. For decades. Google, or go straight to
> > wikipedia.
> > http://en.wikipedia.org/wiki/Microcode
>
> Cool down. I know for waht microcodes are good for.
>
> My question means: What specific bugs/features of my CPU get fixed,
> when I use the microcde included in the recent microcode update???

nobody knows.
 
Old 01-17-2011, 06:57 PM
 
Default Microcode update AMD

Volker Armin Hemmann <volkerarmin@googlemail.com> [11-01-17 20:52]:
> On Monday 17 January 2011 20:19:04 meino.cramer@gmx.de wrote:
> > Volker Armin Hemmann <volkerarmin@googlemail.com> [11-01-17 20:16]:
> > > On Monday 17 January 2011 18:21:48 meino.cramer@gmx.de wrote:
> > > > Hi,
> > > >
> > > > I have two questions:
> > > > 1) Do I have to enable microcode updates in the BIOS of my
> > > > Crosshair
> > > >
> > > > IV Formula to activate microcodes push in the CPU by the
> > > > module
> > > > "microcode" ? (AMD Phenom X6 1090T)
> > >
> > > you ALWAYS have to activate that! This way the bios updates the
> > > microcode with the latest version it is carrying around. Not activating
> > > that option is really, really stupid. For many reasons. It is also
> > > (almost) completely unrelated to that blob.
> > >
> > > That blob is for the OS so you can upload an even more recent version of
> > > microcode. In case your bios sucks. For example.
> > >
> > > > 2) Does anyone know, what these microcodes do? They are fixes
> > > > for...
> > > >
> > > > ...what?
> > >
> > > the CPU. All CPUs use microcode. For decades. Google, or go straight to
> > > wikipedia.
> > > http://en.wikipedia.org/wiki/Microcode
> >
> > Cool down. I know for waht microcodes are good for.
> >
> > My question means: What specific bugs/features of my CPU get fixed,
> > when I use the microcde included in the recent microcode update???
>
> nobody knows.
>

So...why should I try unknown code patched into my CPU.

It looks like "install this virus" from the security point
of view, doesn't ist?
 
Old 01-17-2011, 07:12 PM
Mark Knecht
 
Default Microcode update AMD

On Mon, Jan 17, 2011 at 11:57 AM, <meino.cramer@gmx.de> wrote:
<SNIP>
> So...why should I try unknown code patched into my CPU.
>
> It looks like "install this virus" from the security point
> of view, doesn't ist?

That was my point.

I think the idea Volker is suggesting is the micro-code updates go
from AMD (who understands what the issue is with their processor) to
the BIOS manufacturer (Phoenix or whoever did yous) and get
incorporated in a secure way. They are 'known good' in the BIOS update
we receive and write into a Flash drive. It's just a choice whether
you want to use that part of BOIS or now.

After all, _any_ BIOS update represents an opportunity for someone to
really mess you machine up. Doesn't matter if it's micro-code or
something else.

That's my reading of this so far....

- Mark
 

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