Kernel Update To 6.2 Stable Causes Dell PowerEdge 1750 (SMP) To Freeze On Boot

Robert Watson rwatson at
Fri Feb 23 15:42:29 UTC 2007

On Thu, 22 Feb 2007, Sean Benoit wrote:

> Last fall, while updating a 6.1 Stable kernel to 6.2 Pre-Release, I noted 
> that the then new kernel caused all our previously functioning Dell 
> PowerEdge 1750s (dual processor) to freeze on boot at the point in the boot 
> process where the second processor was being detected. Disabling the second 
> processor in the BIOS served as a temporary workaround and enabled the 
> systems to boot successfully.
> At that time I submitted a PR via the website and a patch was issued within 
> a few hours. The patch resolved the problem. I didn't keep that original 
> correspondence because I assumed that all was well moving forward.
> Last weekend I attempted to update the same systems for the first time since 
> last fall from the patched 6.2 Pre-Release kernel to the new 6.2 Stable 
> kernel. I was alarmed to see that the EXACT same issue had reappeared. The 
> symptoms are exactly the same - as is the workaround (disable the second 
> processor in the BIOS).
> I have once again submitted a PR (109267) via the website (details at 
>; however, I have been 
> advised that I should post the issue to this mailing list instead/prior.
> Not sure what to do from here...

Does this relate to PR 103697 which seems to be a similar correspondence:

Are you using the ULE scheduler?

Robert N M Watson
Computer Laboratory
University of Cambridge

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