On 18.07.2022 13:35, Marek Marczykowski-Górecki wrote:
> On Thu, Jul 14, 2022 at 12:22:36PM +0200, Jan Beulich wrote:
>> On 06.07.2022 17:32, Marek Marczykowski-Górecki wrote:
>>> --- a/xen/drivers/passthrough/amd/iommu_acpi.c
>>> +++ b/xen/drivers/passthrough/amd/iommu_acpi.c
>>> @@ -1078,6 +1078,20 @@ static inline bool_t is_ivmd_block(u8 type)
>>> type == ACPI_IVRS_TYPE_MEMORY_IOMMU);
>>> }
>>>
>>> +static int __init cf_check add_one_extra_ivmd(xen_pfn_t start, xen_ulong_t
>>> nr, u32 id, void *ctxt)
>>> +{
>>> + struct acpi_ivrs_memory ivmd;
>>> +
>>> + ivmd.start_address = start << PAGE_SHIFT;
>>> + ivmd.memory_length = nr << PAGE_SHIFT;
>>
>> Aren't these at risk of truncation on 32-bit architectures? We have
>> suitable wrappers for such conversions, avoiding such issues.
>
> Well, this (and the vtd equivalent) is x86-only, so it's always 64-bit.
Nevertheless writing things cleanly everywhere will reduce the risk of
somebody cloning this code on the assumption that it's correct.
> Anyway, what are those wrappers?
pfn_to_paddr()
Jan
