diff options
Diffstat (limited to 'pkg/sentry/platform/kvm/bluepill_unsafe.go')
| -rw-r--r-- | pkg/sentry/platform/kvm/bluepill_unsafe.go | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/pkg/sentry/platform/kvm/bluepill_unsafe.go b/pkg/sentry/platform/kvm/bluepill_unsafe.go index 2c1e098d7..216d4b4b6 100644 --- a/pkg/sentry/platform/kvm/bluepill_unsafe.go +++ b/pkg/sentry/platform/kvm/bluepill_unsafe.go @@ -61,8 +61,9 @@ func bluepillHandler(context unsafe.Pointer) { } for { - _, _, errno := syscall.RawSyscall(syscall.SYS_IOCTL, uintptr(c.fd), _KVM_RUN, 0) - if errno == syscall.EINTR { + switch _, _, errno := syscall.RawSyscall(syscall.SYS_IOCTL, uintptr(c.fd), _KVM_RUN, 0); errno { + case 0: // Expected case. + case syscall.EINTR: // First, we process whatever pending signal // interrupted KVM. Since we're in a signal handler // currently, all signals are masked and the signal @@ -93,7 +94,20 @@ func bluepillHandler(context unsafe.Pointer) { // Force injection below; the vCPU is ready. c.runData.exitReason = _KVM_EXIT_IRQ_WINDOW_OPEN } - } else if errno != 0 { + case syscall.EFAULT: + // If a fault is not serviceable due to the host + // backing pages having page permissions, instead of an + // MMIO exit we receive EFAULT from the run ioctl. We + // always inject an NMI here since we may be in kernel + // mode and have interrupts disabled. + if _, _, errno := syscall.RawSyscall( + syscall.SYS_IOCTL, + uintptr(c.fd), + _KVM_NMI, 0); errno != 0 { + throw("NMI injection failed") + } + continue // Rerun vCPU. + default: throw("run failed") } |