[Qemu-discuss] DMAR not present in guest

[Pradeep Kiruvale]

Hi All,

I am using linux 4.0 kernel on host side and 3.19 on guest side.

I have enabled the iommu and nested virtualization on host.

The DMAR is visible in the host side and when I start a VM using qemu-kvm, the same DMAR not visible on the guest side. But it says IOMMU is enabled when I look at dmesg.

The qemu verion I am using is 2.3.94

The cli is as below

sudo qemu-system-x86_64 -machine q35 -m 3G -enable-kvm -smp 4  \

 -cpu kvm64,-kvm_pv_eoi,-kvm_steal_time,-kvm_asyncpf,-kvmclock,+vmx,+x2apic \

 -net nic,macaddr=52:54:00:37:4d:10 \

 -net tap,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown \

 -drive file=ubuntu_15.qcow,id=disk,if=none \

 -device ide-hd,drive=disk -serial stdio -serial vc \

 -device intel-hda,addr=1b.0 -device hda-duplex

Please let me know  am I missing something here?  how can I resolve this.

Thanks & Regards,

Pradeep