Split irqchip works based on the fact that we kept the first 24 gsi routing entries inside KVM for userspace ioapic's use. When system boot, we'll reserve these MSI routing entries before hand. However, after migration, we forgot to re-configure it up in the destination side. The result is, we'll get invalid gsi routing entries after migration (all empty), and we get interrupts with vector=0, then strange things happen, like keyboard hang.
The solution is simple - we update them after migration, which is a one line fix in patch 3. The first two patches are things I used for debugging this issue. Though it might not be directly related, I still think it's something good to have in case we encounter similar interrupt issues in the future. Please review, thanks, Peter Xu (3): x86: ioapic: add traces for ioapic x86: ioapic: dump version for "info ioapic" x86: ioapic: fix fail migration when irqchip=split hw/intc/ioapic.c | 22 ++++++++++++++++++++-- hw/intc/ioapic_common.c | 3 ++- hw/intc/trace-events | 7 +++++++ 3 files changed, 29 insertions(+), 3 deletions(-) -- 2.7.4
