If we run with an old kernel that does not support KVM_CAP_IRQ_ROUTING, we don't have to do anything in the ->register_io_adapter and ->io_adapter_map callbacks and therefore should return 0 instead of -ENOSYS (just as the non-kvm flic does).
This fixes using adapter interrupts when running under an older kernel, which broke with "s390x: add I/O adapter registration". Reported-by: Christian Borntraeger <borntrae...@de.ibm.com> Signed-off-by: Cornelia Huck <cornelia.h...@de.ibm.com> --- hw/intc/s390_flic_kvm.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/hw/intc/s390_flic_kvm.c b/hw/intc/s390_flic_kvm.c index 46c9e61..a734094 100644 --- a/hw/intc/s390_flic_kvm.c +++ b/hw/intc/s390_flic_kvm.c @@ -170,7 +170,8 @@ static int kvm_s390_register_io_adapter(S390FLICState *fs, uint32_t id, }; if (!kvm_check_extension(kvm_state, KVM_CAP_IRQ_ROUTING)) { - return -ENOSYS; + /* nothing to do */ + return 0; } r = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr); @@ -195,7 +196,8 @@ static int kvm_s390_io_adapter_map(S390FLICState *fs, uint32_t id, int r; if (!kvm_check_extension(kvm_state, KVM_CAP_IRQ_ROUTING)) { - return -ENOSYS; + /* nothing to do */ + return 0; } r = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr); -- 1.7.9.5