invala

Arun Sharma arun.sharma at intel.com
Wed May 12 18:48:12 PDT 2004


On 5/12/2004 4:28 PM, Marcel Moolenaar wrote:

> On Wed, May 12, 2004 at 03:09:38PM -0700, Arun Sharma wrote:
>> 
>> I noticed that the code in exception.S:TRAP() doesn't invalidate the ALAT 
>> on a register backing store switch. This could be a problem if the kernel 
>> starts using data speculation (say by using a different compiler). However, 
>> restorectx is doing the right thing by using invala.
> 
> Why would this be a problem?
> 

The kernel data speculation might introduce entries into the ALAT which might cause the user data speculation to think that the speculation (advanced load) succeeded, when in fact it has failed.
	
	-Arun



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