Re: [Qemu-ppc] [Qemu-devel] [PATCH] target-ppc: Use right page size with hash table lookup

[David Gibson]

On Mon, Jan 26, 2015 at 07:51:58PM +0530, Aneesh Kumar K.V wrote:
> We look at two sizes specified in ISA (4K, 64K). If not found matching,
> we consider it 16MB.
> 
> Without this patch we would fail to lookup address above 16MB range.
> Below 16MB happened to work before because the kernel have a liner
> mapping and we always looked up hash for 0xc000000000000000. The
> actual real address was computed by using the 16MB offset
> with the real address found with the above hash.
> 
> Without Fix:
> (gdb) x/16x 0xc000000001000000
> 0xc000000001000000 <list_entries+453208>:       Cannot access memory at 
> address 0xc000000001000000
> (gdb)
> 
> With Fix:
> (gdb)  x/16x 0xc000000001000000
> 0xc000000001000000 <list_entries+453208>:       0x00000000      0x00000000    
>   0x00000000      0x00000000
> 0xc000000001000010 <list_entries+453224>:       0x00000000      0x00000000    
>   0x00000000      0x00000000
> 0xc000000001000020 <list_entries+453240>:       0x00000000      0x00000000    
>   0x00000000      0x00000000
> 0xc000000001000030 <list_entries+453256>:       0x00000000      0x00000000    
>   0x00000000      0x00000000
> 
> Signed-off-by: Aneesh Kumar K.V <address@hidden>

This doesn't fully implement the sllp page size encodings, but it's
certainly better than what's there now.

Reviewed-by: David Gibson <address@hidden>

-- 
David Gibson                    | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au  | minimalist, thank you.  NOT _the_ _other_
                                | _way_ _around_!
http://www.ozlabs.org/~dgibson

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