[Crash-utility] [PATCH] s390x: Add 2GB frame support for page table walker

[Dave Anderson]

----- Original Message -----
> Hi Dave,
> 
> On s390 the new zEC12 machines support 2GB frames. In order to walk page tables
> correctly add support to the page table walker function so it detects 2GB frames.
> 
> Michael

Queued for crash-6.1.1.

Thanks,
  Dave

> 
> Signed-off-by: Heiko Carstens <heiko.carstens at de.ibm.com>
> Signed-off-by: Michael Holzheu <holzheu at linux.vnet.ibm.com>
> ---
>  s390x.c |    8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> --- a/s390x.c
> +++ b/s390x.c
> @@ -643,6 +643,13 @@ int s390x_vtop(ulong table, ulong vaddr,
>  		if (!entry)
>  			return FALSE;
>  		table = entry & ~0xfffULL;
> +		/* Check if this a 2GB page */
> +		if ((entry & 0x400ULL) && (level == 1)) {
> +			/* Add the 2GB frame offset & return the final value. */
> +			table &= ~0x7fffffffULL;
> +			*phys_addr = table + (vaddr & 0x7fffffffULL);
> +			return TRUE;
> +		}
>  		len = entry & 0x3ULL;
>  		level--;
>  	}
> @@ -650,6 +657,7 @@ int s390x_vtop(ulong table, ulong vaddr,
>  	/* Check if this is a large page. */
>  	if (entry & 0x400ULL) {
>  		/* Add the 1MB page offset and return the final value. */
> +		table &= ~0xfffffULL;
>  		*phys_addr = table + (vaddr & 0xfffffULL);
>  		return TRUE;
>  	}
>