Re: [PATCH v2 0/5] xen: grant table interface v2 support
From: Boris Ostrovsky
Date: Mon Nov 06 2017 - 15:45:55 EST
On 11/02/2017 05:19 AM, Juergen Gross wrote:
> In order to support Linux to run as a pv guest on machines with huge
> memory (>16TB) or as a hvm guest with more than 16TB of memory the
> kernel has to support grant table interface v2, as v1 is limited to
> 32 bit frame numbers.
>
> This series re-adds that support (it has been removed in 2015) and
> restricts usage of v2 to the features of v1 in order to support
> migration to hosts which only support v1.
>
> V2 is selected only in the following cases:
> - the user has specified v2 via module parameter
> - in a pv guest if the maximum possible memory address of the host is
> above 16TB (memory hotplug taken into account)
> - in a hvm guest if the maximum guest memory address is above 16TB
> (again with memory hotplug taken into account)
>
> Changes in V2:
> - patch 2: remove update_trans_entry() from gnttab_ops (Boris Ostrovsky)
> - added new patch 4
> - patch 5: use cpuid on pv and max_possible_pfn on hvm for version select
>
> Juergen Gross (5):
> xen: re-introduce support for grant v2 interface
> xen: limit grant v2 interface to the v1 functionality
> xen: add grant interface version dependent constants to gnttab_ops
> xen: update arch/x86/include/asm/xen/cpuid.h
> xen: select grant interface version
>
> arch/arm/xen/grant-table.c | 9 +-
> arch/x86/include/asm/xen/cpuid.h | 42 +++++--
> arch/x86/xen/grant-table.c | 60 +++++++++-
> drivers/xen/grant-table.c | 244 +++++++++++++++++++++++++++++++++++----
> include/xen/grant_table.h | 5 +-
> 5 files changed, 318 insertions(+), 42 deletions(-)
>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>