Re: [PATCH v3 1/4] tpm: mark correct memory region range dirty when clearing RAM

[David Hildenbrand <david@redhat.com>]

On 26.07.21 18:57, Peter Xu wrote:
> On Mon, Jul 26, 2021 at 06:03:43PM +0200, David Hildenbrand wrote:
>> We might not start at the beginning of the memory region. Let's
>> calculate the offset into the memory region via the difference in the
>> host addresses.
>>
>> Acked-by: Stefan Berger <stefanb@linux.ibm.com>
>> 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: Eduardo Habkost <ehabkost@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 | 5 ++++-
>>   1 file changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/hw/tpm/tpm_ppi.c b/hw/tpm/tpm_ppi.c
>> index 362edcc5c9..f243d9d0f6 100644
>> --- a/hw/tpm/tpm_ppi.c
>> +++ b/hw/tpm/tpm_ppi.c
>> @@ -30,11 +30,14 @@ 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) {
>> +            hwaddr mr_offs = (uint8_t *)memory_region_get_ram_ptr(block->mr) -
>> +                             block->host_addr;
> 
> Didn't look closely previous - should it be reversed instead?
> 
>    block->host_addr - memory_region_get_ram_ptr(block->mr)

Of course it should :(

Thanks! :)

-- 
Thanks,

David / dhildenb