Hi Eric, just fast-forwarded to the end and noticed this one:
On 06/03/17 11:34, Eric Auger wrote: > Save and restore the pending tables. > > Pending table restore obviously requires the pendbaser to be > already set. > > Signed-off-by: Eric Auger <[email protected]> > > --- > > v1 -> v2: > - do not care about the 1st KB which should be zeroed according to > the spec. > --- > virt/kvm/arm/vgic/vgic-its.c | 71 > ++++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 69 insertions(+), 2 deletions(-) > > diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c > index 27ebabd..24824be 100644 > --- a/virt/kvm/arm/vgic/vgic-its.c > +++ b/virt/kvm/arm/vgic/vgic-its.c > @@ -1736,7 +1736,48 @@ static int lookup_table(struct vgic_its *its, gpa_t > base, int size, int esz, > */ > static int vgic_its_flush_pending_tables(struct vgic_its *its) > { > - return -ENXIO; > + struct kvm *kvm = its->dev->kvm; > + struct vgic_dist *dist = &kvm->arch.vgic; > + struct vgic_irq *irq; > + int ret; > + > + /** > + * we do not take the dist->lpi_list_lock since we have a garantee > + * the LPI list is not touched while the its lock is held Can you elaborate on what gives us this guarantee? I see that we have a locking *order*, but that doesn't mean we can avoid taking the lock. So to me it looks like we need to take the lpi_list_lock spinlock here, which unfortunately breaks the kvm_read_guest() calls below. If you agree on this, you can take a look at the INVALL implementation, where I faced the same issue. The solution we came up with is vgic_copy_lpi_list(), which you can call under the lock to create a (private) copy of the LPI list, which you can later iterate without holding the lock - and thus are free to call sleeping functions. Cheers, Andre. > + */ > + list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) { > + struct kvm_vcpu *vcpu; > + gpa_t pendbase, ptr; > + bool stored; > + u8 val; > + > + vcpu = irq->target_vcpu; > + if (!vcpu) > + return -EINVAL; > + > + pendbase = PENDBASER_ADDRESS(vcpu->arch.vgic_cpu.pendbaser); > + > + ptr = pendbase + (irq->intid / BITS_PER_BYTE); > + > + ret = kvm_read_guest(kvm, (gpa_t)ptr, &val, 1); > + if (ret) > + return ret; > + > + stored = val & (irq->intid % BITS_PER_BYTE); > + if (stored == irq->pending_latch) > + continue; > + > + if (irq->pending_latch) > + val |= 1 << (irq->intid % BITS_PER_BYTE); > + else > + val &= ~(1 << (irq->intid % BITS_PER_BYTE)); > + > + ret = kvm_write_guest(kvm, (gpa_t)ptr, &val, 1); > + if (ret) > + return ret; > + } > + > + return 0; > } > > /** > @@ -1745,7 +1786,33 @@ static int vgic_its_flush_pending_tables(struct > vgic_its *its) > */ > static int vgic_its_restore_pending_tables(struct vgic_its *its) > { > - return -ENXIO; > + struct vgic_irq *irq; > + struct kvm *kvm = its->dev->kvm; > + struct vgic_dist *dist = &kvm->arch.vgic; > + int ret; > + > + list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) { > + struct kvm_vcpu *vcpu; > + gpa_t pendbase, ptr; > + u8 val; > + > + vcpu = irq->target_vcpu; > + if (!vcpu) > + return -EINVAL; > + > + if (!(vcpu->arch.vgic_cpu.pendbaser & GICR_PENDBASER_PTZ)) > + return 0; > + > + pendbase = PENDBASER_ADDRESS(vcpu->arch.vgic_cpu.pendbaser); > + > + ptr = pendbase + (irq->intid / BITS_PER_BYTE); > + > + ret = kvm_read_guest(kvm, (gpa_t)ptr, &val, 1); > + if (ret) > + return ret; > + irq->pending_latch = val & (1 << (irq->intid % BITS_PER_BYTE)); > + } > + return 0; > } > > static int vgic_its_flush_ite(struct vgic_its *its, struct its_device *dev, > _______________________________________________ kvmarm mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
