Rob Bradford 06dc708515 vmm: Only return from reset driven I/O once event received ... The reset system is asynchronous with an I/O event (PIO or MMIO) for ACPI/i8042/CMOS triggering a write to the reset_evt event handler. The VMM thread will pick up this event on the VMM main loop and then trigger a shutdown in the CpuManager. However since there is some delay between the CPU threads being marked to be killed (through the CpuManager::cpus_kill_signalled bool) it is possible for the guest vCPU that triggered the exit to be re-entered when the vCPU KVM_RUN is called after the I/O exit is completed. This is undesirable and in particular the Linux kernel will attempt to jump to real mode after a CMOS based exit - this is unsupported in nested KVM on AMD on Azure and will trigger an error in KVM_RUN. Solve this problem by spinning in the device that has triggered the reset until the vcpus_kill_signalled boolean has been updated indicating that the VMM thread has received the event and called CpuManager::shutdown(). In particular if this bool is set then the vCPU threads will not re-enter the guest. Signed-off-by: Rob Bradford <rbradford@rivosinc.com>		2023-08-04 09:57:25 +08:00
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src	vmm: Only return from reset driven I/O once event received	2023-08-04 09:57:25 +08:00
Cargo.toml	devices: pvpanic: Add pci configuration for pvpanic device	2023-07-06 11:14:54 +01:00