On 3/24/21 8:24 AM, Roger Pau Monne wrote:
> Hello,
>
> This is a proposal for an alternative fix for XSA-369 that instead of
> special casing XEN_UNPOPULATED_ALLOC to size the p2m relies on making
> XEN_BALLOON_MEMORY_HOTPLUG_LIMIT depend on the generic MEMORY_HOTPLUG
> option rather than XEN_BALLOON_MEMORY_HOTPLUG.
>
> I think this is safer, as we don't want to be special casing any option
> that pulls in generic MEMORY_HOTPLUG without XEN_BALLOON_MEMORY_HOTPLUG.
> Without this we would also need to at least special case ZONE_DEVICE
> which also relies on MEMORY_HOTPLUG, and is what pulls the generic
> MEMORY_HOTPLUG option even when XEN_BALLOON_MEMORY_HOTPLUG is disabled
> with XEN_UNPOPULATED_ALLOC.
>
> Thanks, Roger.
>
> Roger Pau Monne (2):
> xen/x86: make XEN_BALLOON_MEMORY_HOTPLUG_LIMIT depend on
> MEMORY_HOTPLUG
> Revert "xen: fix p2m size in dom0 for disabled memory hotplug case"
>
> arch/x86/include/asm/xen/page.h | 12 ------------
> arch/x86/xen/p2m.c | 7 ++-----
> arch/x86/xen/setup.c | 16 ++++++++++++++--
> drivers/xen/Kconfig | 4 ++--
> 4 files changed, 18 insertions(+), 21 deletions(-)
Reviewed-by: Boris Ostrovsky <[email protected]>
On 3/24/21 7:09 PM, Boris Ostrovsky wrote:
> On 3/24/21 8:24 AM, Roger Pau Monne wrote:
>> Hello,
>>
>> This is a proposal for an alternative fix for XSA-369 that instead of
>> special casing XEN_UNPOPULATED_ALLOC to size the p2m relies on making
>> XEN_BALLOON_MEMORY_HOTPLUG_LIMIT depend on the generic MEMORY_HOTPLUG
>> option rather than XEN_BALLOON_MEMORY_HOTPLUG.
>>
>> I think this is safer, as we don't want to be special casing any option
>> that pulls in generic MEMORY_HOTPLUG without XEN_BALLOON_MEMORY_HOTPLUG.
>> Without this we would also need to at least special case ZONE_DEVICE
>> which also relies on MEMORY_HOTPLUG, and is what pulls the generic
>> MEMORY_HOTPLUG option even when XEN_BALLOON_MEMORY_HOTPLUG is disabled
>> with XEN_UNPOPULATED_ALLOC.
>>
>> Thanks, Roger.
>>
>> Roger Pau Monne (2):
>> xen/x86: make XEN_BALLOON_MEMORY_HOTPLUG_LIMIT depend on
>> MEMORY_HOTPLUG
>> Revert "xen: fix p2m size in dom0 for disabled memory hotplug case"
>>
>> arch/x86/include/asm/xen/page.h | 12 ------------
>> arch/x86/xen/p2m.c | 7 ++-----
>> arch/x86/xen/setup.c | 16 ++++++++++++++--
>> drivers/xen/Kconfig | 4 ++--
>> 4 files changed, 18 insertions(+), 21 deletions(-)
>
> Reviewed-by: Boris Ostrovsky <[email protected]>
Applied to for-linus-5.12b.
-boris