Host system crashes on qemu with DMA remapping

[TuniTunes]

Hy,

the host system crashes completely, when i try to pass an physical device without boot option intel_iommu=on set. In older kernel versions you didn't have to pass that option.

I wonder if this can be easily checked by asking iommu state, avoiding a crash of the complete system.

My data:
cpu model: Intel(R) Core(TM) i7 CPU
qemu version: 2.4.1-r2
kernel version: 4.1.2 x86_64
command line:
qemu-system-x86_64 -enable-kvm -drive file=/vms/prod/fw/fw.iso,if=virtio,format=raw -drive file=/vms/prod/fw/swap,if=virtio,format=raw -drive file=/vms/prod/fw/fwdata.iso,if=virtio,format=raw -m 512 -nographic -kernel /data/kernels/vmlinuz-2.6.36-gentoo-r8 -append "root=/dev/vda console=ttyS0 earlyprintk=serial" -net nic,model=virtio,macaddr=DE:AD:BE:EF:2D:AD -net tap,ifname=tapfw0,script=/etc/qemu/qemu-ifup -device pci-assign,host=03:00.0

There are also more detailed informations (if needed) here:
https://forums.gentoo.org/viewtopic-p-7923976.html

Thanks,
Antonios.

[TuniTunes (antonios-dimtsoudis)]

Sorry, i have to cancel this report.

The problem seems to be somewhere else. After some reboots the same issue came up again.

[Thomas Huth (th-huth)]

Triaging old bug tickets ... Can you still reproduce the issue with the latest version of QEMU and the kernel, or could we close this bug nowadays?

[Launchpad Janitor (janitor)]

[Expired for QEMU because there has been no activity for 60 days.]