Re: [XENBUS PATCH v2 1/2] Use Windows 10 APIs to inflate/deflate balloon

[Paul Durrant <xadimgnik@xxxxxxxxx>]

On 11/06/2025 13:36, Tu Dinh wrote:
> Currently the balloon driver allocates pages as normal memory, which
> causes Windows to report the ballooned memory as kernel-allocated
> instead of unavailable.
>
> Windows 10 provides MM_ALLOCATE_AND_HOT_REMOVE to remove pages from
> the physical memory pool. The removed pages can be added back with
> MmAddPhysicalMemory.
>
> Using this feature, the real VM memory capacity will be correctly
> reported in Task Manager.
>
> Balloon deflation is implemented using calls to MmAddPhysicalMemory on
> contiguous PFN ranges.
>
> Signed-off-by: Tu Dinh <ngoc-tu.dinh@xxxxxxxxxx>
> ---
> v2: Updated commit message to say what the patch does. No code change.
> ---
>   src/xenbus/balloon.c | 38 ++++++++++++++++++++++++++++++++++++--
>   1 file changed, 36 insertions(+), 2 deletions(-)
Reviewed-by: Paul Durrant <paul@xxxxxxx>