# Re: \[PATCH v3\] x86/Hyper-V: Support for free page reporting

- From: Wei Liu \<wei.liu@kernel.org\>
- Date: 2021-01-27 00:28:09 
- List: linux-hyperv
- Page: https://ratatoskr.run/linux-hyperv/2021/01/6248542
- Thread: https://ratatoskr.run/linux-hyperv/2021/01/6225977/t.md

```text
On Wed, Jan 06, 2021 at 11:20:33PM +0000, Sunil Muthuswamy wrote:
> Linux has support for free page reporting now (36e66c554b5c) for
> virtualized environment. On Hyper-V when virtually backed VMs are
> configured, Hyper-V will advertise cold memory discard capability,
> when supported. This patch adds the support to hook into the free
> page reporting infrastructure and leverage the Hyper-V cold memory
> discard hint hypercall to report/free these pages back to the host.
> 
> Signed-off-by: Sunil Muthuswamy <redacted>
> Tested-by: Matheus Castello <matheus@castello.eng.br>

Reviewed-by: Wei Liu <wei.liu@kernel.org>
```