Hi all, after migrating a Jailhouse VM to a newer host platform with shadow VMCS support I found a bug. As you may know, Jailhouse doesn't intercept interrupts, thus also never requests an interrupt window. Nevertheless: qemu-system-x86-5777 [001] 74970.625324: kvm_mmio: mmio write len 4 gpa 0xfebf5008 val 0x20 qemu-system-x86-5777 [001] 74970.625325: kvm_userspace_exit: reason KVM_EXIT_MMIO (6) qemu-system-x86-5777 [001] 74970.625330: kvm_entry: vcpu 1 qemu-system-x86-5777 [001] 74970.625333: kvm_exit: reason PENDING_INTERRUPT rip 0xffffffff81043e54 info 0 0 qemu-system-x86-5777 [001] 74970.625333: kvm_nested_vmexit: rip: 0xffffffff81043e54 reason: PENDING_INTERRUPT ext_inf1: 0x0000000000000000 ext_inf2: 0x0000000000000000 ext_int: 0x00000000 ext_int_err: 0x00000000 qemu-system-x86-5777 [001] 74970.625334: kvm_nested_vmexit_inject: reason: PENDING_INTERRUPT ext_inf1: 0x0000000000000000 ext_inf2: 0x0000000000000000 ext_int: 0x00000000 ext_int_err: 0x00000000 qemu-system-x86-5777 [001] 74970.625339: kvm_entry: vcpu 1 qemu-system-x86-5777 [001] 74970.625341: kvm_exit: reason EPT_MISCONFIG rip 0xfffffffff0002307 info 0 0 qemu-system-x86-5777 [001] 74970.625343: kvm_emulate_insn: 0:fffffffff0002307:8b 40 20 (prot64) And then Jailhouse crashes (which is also interesting to understand why - L1 host state is corrupt). Anyway, the point is that we leak CPU_BASED_VIRTUAL_INTR_PENDING from L0 into vmcs12. L0 sets it before entering L2, and then we transfer it from the hardware state to vmc12 on exit because that VMCS field is shadowed. The crash disappears when disabling VMCS shadowing. Can we simply stop shadowing CPU_BASED_VM_EXEC_CONTROL when CPU_BASED_VIRTUAL_INTR_PENDING is injected to L2? Jan -- Siemens AG, Corporate Technology, CT RTC ITP SES-DE Corporate Competence Center Embedded Linux -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
