| Message ID | 20201017210102.26036-1-eafanasova@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | accel/kvm: add PIO ioeventfds only in case kvm_eventfds_allowed is true | expand |
On Sat, Oct 17, 2020 at 02:01:01PM -0700, Elena Afanasova wrote: > Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> > Signed-off-by: Elena Afanasova <eafanasova@gmail.com> > --- > accel/kvm/kvm-all.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) Additional information for the commit description: MMIO eventfd_add/del are only registered when kvm_eventfds_allowed is true but for PIO they are registered unconditionally. This is a bug because kvm.ko ioeventfd should not be used if kvm_eventfds_allowed is false. This issue is a latent bug because ioeventfd is usually available when KVM is enabled. > > diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c > index 9ef5daf4c5..baaa54249d 100644 > --- a/accel/kvm/kvm-all.c > +++ b/accel/kvm/kvm-all.c > @@ -2239,8 +2239,10 @@ static int kvm_init(MachineState *ms) > > kvm_memory_listener_register(s, &s->memory_listener, > &address_space_memory, 0); > - memory_listener_register(&kvm_io_listener, > - &address_space_io); > + if (kvm_eventfds_allowed) { > + memory_listener_register(&kvm_io_listener, > + &address_space_io); > + } > memory_listener_register(&kvm_coalesced_pio_listener, > &address_space_io); > > -- > 2.25.1 >
On Sat, Oct 17, 2020 at 02:01:01PM -0700, Elena Afanasova wrote: > Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> > Signed-off-by: Elena Afanasova <eafanasova@gmail.com> > --- > accel/kvm/kvm-all.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) Thanks, applied just this patch to my block-next tree: https://github.com/stefanha/qemu/commits/block-next Stefan
diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index 9ef5daf4c5..baaa54249d 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -2239,8 +2239,10 @@ static int kvm_init(MachineState *ms) kvm_memory_listener_register(s, &s->memory_listener, &address_space_memory, 0); - memory_listener_register(&kvm_io_listener, - &address_space_io); + if (kvm_eventfds_allowed) { + memory_listener_register(&kvm_io_listener, + &address_space_io); + } memory_listener_register(&kvm_coalesced_pio_listener, &address_space_io);