On Dec 14, 7:02 pm, Yousuf Khan <bbb...@[EMAIL PROTECTED]
> wrote:
> Robert Myers wrote:
> > A number of assertions have been made here about the AMD TLB L3 Bug:
>
> > 1. Only affects virtualization.
>
> > 2. Is fixed in 64-bit Linux without a significant performance hit.
>
> > 1. TRUTH: AMD, which knew about the bug before the chip was released,
> > falsely made this claim. The bug apparently affects all workloads,
> > potentially resulting in a system freeze.
>
> The truth actually is that it only affects virtualized workloads,
> because the problem occurs when nested page tables are used. Nested page
> tables only are used in virtualization, no other times. AMD never made
> the claim it only affects virtualization, it is actually trying to keep
> that hushed up: I assume because it does not want a virtualization bug
> to be associated with its products since that kind of a reputation would
> be hard to shake off, even if fixed.
>
Discussing AMD with you can be an interesting undertaking:
"In order to better understand this problem, TR spoke with Michael
Saucier, Desktop Product Marketing Manager at AMD. Saucier confirmed
that the TLB erratum can cause the system to hang when the chip is
experiencing high utilization. AMD has stated previously that
virtualization workloads can lead to this problem, but Saucier
clarified that other workloads can trigger system hangs, as well. He
characterized the issue as a race condition in the TLB logic "where
the other guy wins who isn't supposed to win," and said the likelihood
of the erratum causing a system hang is extremely rare."
The re****t could be factually incorrect, but since I cited something
other than my own impression to sup****t my statement, I'd expect you
to do the same.
You know that I'm not an admirer of AMD, so you won't be surprised
that I think AMD may be mortally wounded. Between the ATI fiasco and
this, AMD is a company with products that no one is going to want to
buy and seems unlikely to survive until it will have products that
someone does want to buy. That AMD is publicly whining about the
pounding its stock price has taken should tell you something. Vendors
who *finally* took a chance on AMD after years of hanging back have
been fried. First there was the lame roadmap. Now this.
What's the difference between this and Intel's botched FDIV bug?
Very, very simple. At the time of the FDIV bug, x86 was for
"peecees," and no one cared if Intel made mistakes that IBM (or DEC or
Sun) never would. Now they do.
> > 2. TRUTH: A fix is available under NDA for RHEL 4 and not otherwise
> > apparently.
>
> >http://techre****t.com/discussions.x/13721
>
> >http://techre****t.com/discussions.x/13724
>
> How secret can it be if it's open-source?
>
How is part of SUSE kept proprietary?
Robert.
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