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General Category => General => Topic started by: Jeremy Collake on March 07, 2012, 08:27:23 AM

Title: NEWS: AMD CPU Hardware bug can lead to stack corruption -not related to our soft
Post by: Jeremy Collake on March 07, 2012, 08:27:23 AM
This has nothing to do with our software, though is big news just announced.

Please see: https://plus.google.com/b/111452122533164797807/111452122533164797807/posts/eYYUEo1AFAo

Details: http://thread.gmane.org/gmane.os.dragonfly-bsd.kernel/14471

AMD confirmation: http://article.gmane.org/gmane.os.dragonfly-bsd.kernel/14518
Title: Re: NEWS: AMD CPU Hardware bug can lead to stack corruption -not related to our soft
Post by: Hotrod on March 07, 2012, 03:26:17 PM
Can ya dumb it down a lil for us challenged ones?  :o ;)
Title: Re: NEWS: AMD CPU Hardware bug can lead to stack corruption -not related to our soft
Post by: edkiefer on March 07, 2012, 07:36:00 PM
the way I read it (I don't understand all terminology either) is this guy found a bug in Hardware under a certain condition the out data gets corrupted (at memory address ? ) .
He then mad a more simple test to show AMD what it takes to reproduce it fast .

AFAIK , CPU and its micro code sometimes does have erratic errors but many times there work around to them or there in trouble  :)

What was interesting is this happened in a simple single threaded run , I am not sure what app he was running or if he was compiling code when this happened originally so not sure how rare this is, probably pretty rare .
Title: Re: NEWS: AMD CPU Hardware bug can lead to stack corruption -not related to our soft
Post by: Jeremy Collake on March 07, 2012, 08:59:14 PM
Yes, it is an extremely rare condition. None-the-less, in these conditions, corruption of the stack pointer can occur, causing (most often) a crash of the immediate process. If it occurred in a kernel mode component, it would be a BSOD. Fortunately, the frequency of these occurrences is surely so rare that none of us have ever seen it.
Title: Re: NEWS: AMD CPU Hardware bug can lead to stack corruption -not related to our soft
Post by: Jeremy Collake on March 08, 2012, 11:40:22 AM
The funny thing is that tech media on the web is too busy writing for their advertisers to report on real news these days, lol.
Title: Re: NEWS: AMD CPU Hardware bug can lead to stack corruption -not related to our soft
Post by: Hotrod on March 08, 2012, 01:49:39 PM
Quote[â€"] (http://www.reddit.com/r/ReverseEngineering/comments/qjzkf/amd_cpu_bug_causing_stack_pointer_corruption/#)DasWood (http://www.reddit.com/user/DasWood) 7 points 1 day agoThe tested and affected CPUs are
AMD Opteron(tm) Processor 6168 (1900.01-MHz K8-class CPU)
AMD Phenom(tm) II X4 820 Processor (2799.92-MHz K8-class CPU)
 

       
  • permalink (http://www.reddit.com/r/ReverseEngineering/comments/qjzkf/amd_cpu_bug_causing_stack_pointer_corruption/c3y6ylh)


I have one of the Sempron 3100+ , hope it doesn't go back that far.  :(
Title: Re: NEWS: AMD CPU Hardware bug can lead to stack corruption -not related to our soft
Post by: Jeremy Collake on March 08, 2012, 02:01:48 PM
Dunno. It goes back a long way, but nobody knows how far yet I think. It would be interesting to get the code sample together. For accuracy, it may require a USB key and micro-OS to replicate reliably though, as so many variables are involved.
Title: Re: NEWS: AMD CPU Hardware bug can lead to stack corruption -not related to our soft
Post by: edkiefer on March 08, 2012, 03:50:06 PM
http://en.wikipedia.org/wiki/List_of_AMD_Sempron_microprocessors

Sempron 3100+ was released 2005 and is 754 socket which is like 3 -4 sockets back from K8 series so it could be in it but that is a lot different cpu .

http://products.amd.com/en-us/DesktopCPUResult.aspx

As Jeremy said it would need testing to make sure .