Re: 2.6.14-rc3-rt2

[Andi Kleen]

On Thu, Oct 06, 2005 at 10:10:55AM +0200, Ingo Molnar wrote:
> 
> * Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
> 
> > Found the problem.  You're using a 64 bit machine and flags in the 
> > acpi code is defined as u32 and not unsigned long.  Ingo's tests put 
> > some checks in the flags at the MSBs and these are being truncated.
> 
> ahh ... I would not be surprised if this caused actual problems on x64 
> in the upstream kernel too: using save_flags() over u32 will corrupt a 
> word on the stack ...
> 
> Andi?

Yes it should be using unsigned long. The actual flag word is still
only 32bit, but the inline assembly expects 64bit. And save_flags 
might corrupt the target if it's too small.

Normally you should get a warning from warn_if_not_ulong() though.
You didn't get it in that case?  I don't remember any such warnings
from the ACPI code.

Which code does it exactly? 

-Andi
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