On Tue, Dec 16, 2025 at 02:20:29PM +0000, Anirudh Rayabharam wrote:
> From: Anirudh Rayabharam (Microsoft) <[email protected]>
>
> The mshv driver now uses movable pages for guests. For arm64 guests
> to be functional, handle gpa intercepts for arm64 too (the current
> code implements handling only for x86). Without this, arm64 guests are
> broken.
>
> Move some arch-agnostic functions out of #ifdefs so that they can be
> re-used.
>
> Signed-off-by: Anirudh Rayabharam (Microsoft) <[email protected]>
> ---
> drivers/hv/mshv_root_main.c | 38 ++++++++++++++++++++++++++++---------
> 1 file changed, 29 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/hv/mshv_root_main.c b/drivers/hv/mshv_root_main.c
> index 9cf28a3f12fe..882605349664 100644
> --- a/drivers/hv/mshv_root_main.c
> +++ b/drivers/hv/mshv_root_main.c
> @@ -608,7 +608,6 @@ mshv_partition_region_by_gfn(struct mshv_partition
> *partition, u64 gfn)
> return NULL;
> }
>
> -#ifdef CONFIG_X86_64
> static struct mshv_mem_region *
> mshv_partition_region_by_gfn_get(struct mshv_partition *p, u64 gfn)
> {
> @@ -625,6 +624,34 @@ mshv_partition_region_by_gfn_get(struct mshv_partition
> *p, u64 gfn)
> return region;
> }
>
> +#ifdef CONFIG_X86_64
> +static u64 mshv_get_gpa_intercept_gfn(struct mshv_vp *vp)
> +{
> + struct hv_x64_memory_intercept_message *msg;
> + u64 gfn;
> +
> + msg = (struct hv_x64_memory_intercept_message *)
> + vp->vp_intercept_msg_page->u.payload;
> +
> + gfn = HVPFN_DOWN(msg->guest_physical_address);
> +
> + return gfn;
> +}
> +#else /* CONFIG_X86_64 */
It's better to explicitly branch for ARM64 here for clarity as
hv_arm64_memory_intercept_message is defined only for ARM64.
> +static u64 mshv_get_gpa_intercept_gfn(struct mshv_vp *vp)
> +{
> + struct hv_arm64_memory_intercept_message *msg;
> + u64 gfn;
> +
> + msg = (struct hv_arm64_memory_intercept_message *)
> + vp->vp_intercept_msg_page->u.payload;
> +
> + gfn = HVPFN_DOWN(msg->guest_physical_address);
> +
> + return gfn;
> +}
> +#endif /* CONFIG_X86_64 */
> +
Are these functions really needed?
It would be clearer (and shorter) to branch directly in
mshv_handle_gpa_intercept.
Thanks,
Stanislav
> /**
> * mshv_handle_gpa_intercept - Handle GPA (Guest Physical Address)
> intercepts.
> * @vp: Pointer to the virtual processor structure.
> @@ -640,14 +667,10 @@ static bool mshv_handle_gpa_intercept(struct mshv_vp
> *vp)
> {
> struct mshv_partition *p = vp->vp_partition;
> struct mshv_mem_region *region;
> - struct hv_x64_memory_intercept_message *msg;
> bool ret;
> u64 gfn;
>
> - msg = (struct hv_x64_memory_intercept_message *)
> - vp->vp_intercept_msg_page->u.payload;
> -
> - gfn = HVPFN_DOWN(msg->guest_physical_address);
> + gfn = mshv_get_gpa_intercept_gfn(vp);
>
> region = mshv_partition_region_by_gfn_get(p, gfn);
> if (!region)
> @@ -663,9 +686,6 @@ static bool mshv_handle_gpa_intercept(struct mshv_vp *vp)
>
> return ret;
> }
> -#else /* CONFIG_X86_64 */
> -static bool mshv_handle_gpa_intercept(struct mshv_vp *vp) { return false; }
> -#endif /* CONFIG_X86_64 */
>
> static bool mshv_vp_handle_intercept(struct mshv_vp *vp)
> {
> --
> 2.34.1
>
