On 7/23/25 06:18, Jan Beulich wrote:
> On 13.06.2025 17:17, Stewart Hildebrand wrote:
>> --- a/xen/arch/arm/Kconfig
>> +++ b/xen/arch/arm/Kconfig
>> @@ -8,6 +8,8 @@ config ARM_64
>> depends on !ARM_32
>> select 64BIT
>> select HAS_FAST_MULTIPLY
>> + select HAS_VPCI_GUEST_SUPPORT if PCI_PASSTHROUGH
>> + select HAS_PASSTHROUGH if PCI_PASSTHROUGH
>
> As I just learned, this change (or maybe it was the "select HAS_PCI"
> further down) has exposed the quarantining Kconfig option prompt, which
> (aiui) is entirely meaningless on Arm. IOW I think further adjustments
> are necessary.
>
> Jan
Not entirely meaningless - the choice between "none" and "basic" still
seems relevant. Just "scratch page" quarantining hasn't been implemented
in any of the Arm iommu drivers.
Perhaps just the IOMMU_QUARANTINE_SCRATCH_PAGE option should be hidden
on Arm (or only exposed on x86)? E.g.:
diff --git a/xen/drivers/passthrough/Kconfig b/xen/drivers/passthrough/Kconfig
index 561f9694b2a6..51c54ed530b0 100644
--- a/xen/drivers/passthrough/Kconfig
+++ b/xen/drivers/passthrough/Kconfig
@@ -90,4 +90,5 @@ choice
bool "basic"
config IOMMU_QUARANTINE_SCRATCH_PAGE
bool "scratch page"
+ depends on X86
endchoice
