qemu-system-ppc64: ../system/memory.c:2666: memory_region_add_subregion_common: Assertion `!subregion->container' failed.

[Michal Suchánek]

Hello,

reportedly since the inclusion of Linux patch
6aa989ab2bd0d37540c812b4270006ff794662e7 powerpc/pseries/iommu: memory
notifier incorrectly adds TCEs for pmemory

qemu fails to reboot VM. When running Linux with this patch inside VM
qemu crashes due to assertion failure:

KVM: Failed to create TCE64 table for liobn 0x80000001
qemu-system-ppc64: ../system/memory.c:2666:
memory_region_add_subregion_common: Assertion `!subregion->container'
failed.
Aborted (core dumped)

This only happens for VMs with a PCI device.

qemu-system-ppc64 --enable-kvm -m 4096 -smp 8 -hda SLE15.qcow -vga none
-nographic

reboots fine but

qemu-system-ppc64 --enable-kvm -m 4096 -smp 8 -hda SLE15.qcow -vga none
-nographic -device qemu-xhci

This has been reproduced with qemu 8.2 and 9.2

It seems failry easy to reproduce but I can provide specific kernel
configuration or kernel binaries if needed.

Thanks

Michal