Most machines don't allow sysbus devices like "kvmclock" to be
created from the command-line, but some of them do (the ones with
has_dynamic_sysbus=true). In those cases, it's possible to
manually create a kvmclock device without KVM being enabled,
making QEMU crash:
$ qemu-system-x86_64 -machine q35,accel=tcg -device kvmclock
Segmentation fault (core dumped)
This changes kvmclock's realize method to return an error if KVM
is disabled, to ensure it won't crash QEMU.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <
20170309185046.17555-1-ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
#include "kvm_i386.h"
#include "hw/sysbus.h"
#include "hw/kvm/clock.h"
+#include "qapi/error.h"
#include <linux/kvm.h>
#include <linux/kvm_para.h>
{
KVMClockState *s = KVM_CLOCK(dev);
+ if (!kvm_enabled()) {
+ error_setg(errp, "kvmclock device requires KVM");
+ return;
+ }
+
kvm_update_clock(s);
qemu_add_vm_change_state_handler(kvmclock_vm_state_change, s);