On Monday 06 December 2010 20:58:10 Avi Kivity wrote: > On 12/06/2010 10:44 AM, Sheng Yang wrote: > > Seems we missed it. > > > > Signed-off-by: Sheng Yang<sheng@xxxxxxxxxxxxxxx> > > --- > > Do we need this, or slot_lock covered this? > > > > virt/kvm/kvm_main.c | 24 ++++++++++++++++-------- > > 1 files changed, 16 insertions(+), 8 deletions(-) > > > > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > > index c4ee364..3e71b91 100644 > > --- a/virt/kvm/kvm_main.c > > +++ b/virt/kvm/kvm_main.c > > @@ -2228,28 +2228,36 @@ static void kvm_io_bus_destroy(struct kvm_io_bus > > *bus) > > > > int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr, > > > > int len, const void *val) > > > > { > > > > - int i; > > + int i, idx, r = -EOPNOTSUPP; > > > > struct kvm_io_bus *bus; > > > > + idx = srcu_read_lock(&kvm->srcu); > > > > bus = srcu_dereference(kvm->buses[bus_idx],&kvm->srcu); > > for (i = 0; i< bus->dev_count; i++) > > > > - if (!kvm_iodevice_write(bus->devs[i], addr, len, val)) > > - return 0; > > - return -EOPNOTSUPP; > > + if (!kvm_iodevice_write(bus->devs[i], addr, len, val)) { > > + r = 0; > > + break; > > + } > > + srcu_read_unlock(&kvm->srcu, idx); > > + return r; > > > > } > > Isn't this already taken care of by srcu_read_lock() in > vcpu_enter_guest(), just before calling ->handle_exit()? Yes, finally found it. So big reading critical region... -- regards Yang, Sheng -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html