Re: Did the latest QEMU emulated SMMUv3 not support "smmu sva" function ?

[Eric Auger <eric.auger@redhat.com>]

Hi,

On 10/10/25 2:01 AM, tugouxp wrote:
> Hi folks:
>   i start my aacrh64 qemu platforms with command:
> "qemu-system-aarch64 -m 512M -smp 4 -cpu cortex-a57 -machine
> virt,*iommu=smmuv3* -kernel arch/arm64/boot/Image -append
> "rdinit=/linuxrc nokaslr console=ttyAMA0 loglevel=8" -nographic"
> and found it does not work normally with MULT substream(PASID), after
> review the qemu smmuv3.c i made some discovery,  the smmu IDR1
> register  SSIDSIZE did not initialized for the default value of
> emulated "SSIDSIZE" in SMMU IDR1 is 0, which means only support one
> sub stream(pasid), so that is why does not work.
I confirm PASIDs are not yet supported by the vSMMU.
>
> so here i want to get a information is that, did the latest qemu did
> not support SVA mechanis about IOMMU ? and did all the others platfrom
> like arm on this function?  thanks for your kindly help.
vSVA is not yet supported either. This is under work in [PATCH v4 00/27]
hw/arm/virt: Add support for user-creatable accelerated SMMUv3

Thanks

Eric

>
>  
> BRs
> zlcao