Re: [PATCH v2] hvf: Avoid mapping regions < PAGE_SIZE as ram

[Philippe Mathieu-Daudé]

On 10/25/21 15:21, Alexander Graf wrote:
> HVF has generic memory listener code that adds all RAM regions as HVF RAM
> regions. However, HVF can only handle page aligned, page granule regions.
> 
> So let's ignore regions that are not page aligned and sized. They will be
> trapped as MMIO instead.
> 
> Signed-off-by: Alexander Graf <agraf@csgraf.de>
> 
> ---
> 
> v1 -> v2:
> 
>   - Use QEMU_IS_ALIGNED()
> ---
>  accel/hvf/hvf-accel-ops.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/accel/hvf/hvf-accel-ops.c b/accel/hvf/hvf-accel-ops.c
> index 2b2c411076..54457c76c2 100644
> --- a/accel/hvf/hvf-accel-ops.c
> +++ b/accel/hvf/hvf-accel-ops.c
> @@ -122,6 +122,7 @@ static void hvf_set_phys_mem(MemoryRegionSection 
> *section, bool add)
>      MemoryRegion *area = section->mr;
>      bool writeable = !area->readonly && !area->rom_device;
>      hv_memory_flags_t flags;
> +    uint64_t page_size = qemu_real_host_page_size;
>  
>      if (!memory_region_is_ram(area)) {
>          if (writeable) {
> @@ -135,6 +136,12 @@ static void hvf_set_phys_mem(MemoryRegionSection 
> *section, bool add)
>          }
>      }
>  
> +    if (!QEMU_IS_ALIGNED(int128_get64(section->size), page_size) ||
> +        !QEMU_IS_ALIGNED(section->offset_within_address_space, page_size)) {
> +        /* Not page aligned, so we can not map as RAM */
> +        add = false;
> +    }
> +
>      mem = hvf_find_overlap_slot(
>              section->offset_within_address_space,
>              int128_get64(section->size));
> 

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>