On 23 November 2012 10:18, Jens Freimann <jf...@linux.vnet.ibm.com> wrote:
> + /* The initial reset call is needed here to reset in-kernel
> + * vcpu data that we can't access directly from QEMU.
If there's in-kernel vcpu data we can't access from QEMU,
doesn't this cause problems for migration?
> Before
> + * this ioctl cpu_synchronize_state() is called in common kvm
> + * code (kvm-all). What remains is clearing registers and psw
> + * in QEMU cpu state */
> + if (kvm_vcpu_ioctl(env, KVM_S390_INITIAL_RESET, NULL)) {
> + perror("Can't reset vcpu\n");
> + }
Doesn't this mean we're now out-of-sync again, since the
kernel state will be whatever INITIAL_RESET says it should
be but the QEMU state won't have been changed?
Generally, I think an arch-independent 'reset vcpu' ioctl
would be useful. At the moment for ARM you have to pull
everything out and back in again via the GET/SET_REG interface,
which works [you can keep all the state around to write back
on vcpu reset] but is ugly.
-- PMM
