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Subject: Re: TLB miss handlers
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On Friday 28 January 2005 11:53, Christian Hildner wrote:
> Hi,
>
> looking at entry 0x0400 of the interrupt table I am wondering about
> the following lines:
>
> IVT_ENTRY(Instruction_TLB, 0x0400)
>     mov r16=cr.ifa
>     mov r17=pr
>     ;;
>     thash   r18=r16
>     ttag    r19=r16
>     ;;
>     add r21=16,r18      // tag
>     add r20=24,r18      // collision chain
>     ;;
>     ld8 r21=[r21]       // check VHPT tag
>     ^^^^^^^^^^
> Are you sure you cannot enter a nested TLB miss fault here on IA64
> implementations that do not have the VHPT walker implemented? You
> wouldn't get fault 0x0000 since there is no walker that throws that
> fault.

When I wrote this originally, I had the VHPT mapped by a TR. I believe 
this is still the case.