https://bugzilla.kernel.org/show_bug.cgi?id=215964 Bug ID: 215964 Summary: nVMX: KVM(L0) does not perform a platform reboot when guest(L2) trigger a reboot event through IO-Port-0xCF9 Product: Virtualization Version: unspecified Kernel Version: 5.10+ Hardware: Intel OS: Linux Tree: Mainline Status: NEW Severity: high Priority: P1 Component: kvm Assignee: virtualization_kvm@xxxxxxxxxxxxxxxxxxxx Reporter: yadong.qi@xxxxxxxxx Regression: No Background: We have a lightweight Hypervisor(iKGT) which aims to monitor very limited resources and passthrough most resources to its guest. The IO-Port:0x3F9 is also passthrough to its guest, so when guest tries to trigger a reboot event(through IO-port:0x3F9), the hardware will do the platform reset directly. We ported it to running under KVM, then it becomes nested virtualization architecture: KVM(L0), iKGT(L1), Guest(L2). Reproduce Steps: Guest(L2) write 0xCF9 to trigger a platform reboot. Expected result: KVM perform a virtual platform reset and reboot guest. Current result: It seems KVM only reset part of the vCPU(L2), but it does not clear the nVMX state, it still tries to emulate VMExit to iKGT(L1). We still can observe VMExit from iKGT(L1) and the exit reason is not expected. -- You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.
