Re: [PATCH v1 1/5] tpm: mark correct memory region range dirty when clearing RAM

[Stefan Berger <stefanb@linux.ibm.com>]

On 2/10/21 12:15 PM, David Hildenbrand wrote:
> We might not start at the beginning of the memory region. We could also
> calculate via the difference in the host address; however,
> memory_region_set_dirty() also relies on memory_region_get_ram_addr()
> internally, so let's just use that.
>
> Fixes: ffab1be70692 ("tpm: clear RAM when "memory overwrite" requested")
> Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Cc: "Michael S. Tsirkin" <mst@redhat.com>
> Cc: Alex Williamson <alex.williamson@redhat.com>
> Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
> Cc: Igor Mammedov <imammedo@redhat.com>
> Cc: Claudio Fontana <cfontana@suse.de>
> Cc: Thomas Huth <thuth@redhat.com>
> Cc: "Alex Bennée" <alex.bennee@linaro.org>
> Cc: Peter Xu <peterx@redhat.com>
> Cc: Laurent Vivier <lvivier@redhat.com>
> Cc: Stefan Berger <stefanb@linux.vnet.ibm.com>
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
>   hw/tpm/tpm_ppi.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/hw/tpm/tpm_ppi.c b/hw/tpm/tpm_ppi.c
> index 72d7a3d926..e0e2d2c8e1 100644
> --- a/hw/tpm/tpm_ppi.c
> +++ b/hw/tpm/tpm_ppi.c
> @@ -30,11 +30,13 @@ void tpm_ppi_reset(TPMPPI *tpmppi)
>           guest_phys_blocks_init(&guest_phys_blocks);
>           guest_phys_blocks_append(&guest_phys_blocks);
>           QTAILQ_FOREACH(block, &guest_phys_blocks.head, next) {
> +            ram_addr_t mr_start = memory_region_get_ram_addr(block->mr);
> +
>               trace_tpm_ppi_memset(block->host_addr,
>                                    block->target_end - block->target_start);
>               memset(block->host_addr, 0,
>                      block->target_end - block->target_start);
> -            memory_region_set_dirty(block->mr, 0,
> +            memory_region_set_dirty(block->mr, block->target_start - mr_start,
>                                       block->target_end - block->target_start);
>           }
>           guest_phys_blocks_free(&guest_phys_blocks);

Acked-by: Stefan Berger <stefanb@linux.ibm.com>