On Tue, 6 Aug 2024 at 08:10, Daniel Wagner [off-list ref] wrote:

The only stall I was able to trigger
reliable was with qemu's PCI emulation. It looks like when a CPU is
offlined, the PCI affinity is reprogrammed but qemu still routes IRQs to
an offline CPU instead to newly programmed destination CPU. All worked
fine on real hardware.

Hi Daniel,
Please file a QEMU bug report here (or just reply to this emails with
details on how to reproduce the issue and I'll file the issue on your
behalf):
https://gitlab.com/qemu-project/qemu/-/issues

We can also wait until your Linux patches have landed if that makes it
easier to reproduce the bug.

Thanks!

Stefan