• make minimalistic driver that requests IRQ on load and release it on unload;
• pass IRQ no. as a module parameter;
• (variation) make ISR lock spinlock and not release it; see how it looks;
• (extra) modify qemu to allow emitting IRQ from monitor;

TBD

• initramfs is fun: bzImage holds rootfs and re-builds it even if kernel code is not changed;
• spinlock re-acquisition locks up hard;
• qemu internal hardware objects are not that easily navigable – to be continued;