log_start might be called by memory.c just before registering the section. So we can actually get a log_start without a region_add, which we can silently ignore.
This makes current KVM code trigger an assertion ("kvm_section_update_flags: error finding slot"). Also, if we want to trap every access to a section, we might not have a slot. So let's just tolerate if we don't have a slot. Fixes: 343562e8fa22 ("kvm: kvm_log_start/stop are only called with known sections") Reported-by: Thomas Huth <th...@redhat.com> Signed-off-by: David Hildenbrand <da...@redhat.com> --- accel/kvm/kvm-all.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index 90c88b517d..64de8461e0 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -394,8 +394,11 @@ static int kvm_section_update_flags(KVMMemoryListener *kml, mem = kvm_lookup_matching_slot(kml, start_addr, size); if (!mem) { - fprintf(stderr, "%s: error finding slot\n", __func__); - abort(); + /* + * log_start() might be called before region_add(), and sometimes + * we don't have a slot as we want to trap every access. + */ + return 0; } return kvm_slot_update_flags(kml, mem, section->mr); -- 2.13.5