On Thu, May 04, 2017 at 01:44:28PM +0200, Eric Auger wrote: > GITS_CREADR needs to be restored so let's implement the associated > uaccess_write_its callback. The write only is allowed if the its > is disabled. > > Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx> > > --- > v5 -> v6: > - remove usage of update_64bit_reg and check alignment of cmd offset > > v4 -> v5: > - keep Stalled bit > - vgic_mmio_uaccess_write_its_creadr can now return an error > > v3 -> v4: > - REGISTER_ITS_DESC_UACCESS now introduced in this patch > - we now check the its is disabled > --- > virt/kvm/arm/vgic/vgic-its.c | 43 +++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 41 insertions(+), 2 deletions(-) > > diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c > index 222fad5..18588ef 100644 > --- a/virt/kvm/arm/vgic/vgic-its.c > +++ b/virt/kvm/arm/vgic/vgic-its.c > @@ -1213,6 +1213,34 @@ static unsigned long vgic_mmio_read_its_creadr(struct kvm *kvm, > return extract_bytes(its->creadr, addr & 0x7, len); > } > > +static int vgic_mmio_uaccess_write_its_creadr(struct kvm *kvm, > + struct vgic_its *its, > + gpa_t addr, unsigned int len, > + unsigned long val) > +{ > + u32 cmd_offset; > + int ret = 0; > + > + mutex_lock(&its->cmd_lock); > + > + if (its->enabled) { > + ret = -EBUSY; > + goto out; > + } > + > + cmd_offset = ITS_CMD_OFFSET(val); > + if ((cmd_offset >= ITS_CMD_BUFFER_SIZE(its->cbaser)) || > + (cmd_offset & 0x1F)) { > + ret = -EINVAL; > + goto out; > + } > + > + its->creadr = val; do we let userspace decide the stalled bit or should we use ITS_CMD_OFFSET() when assigning the field as well? > +out: > + mutex_unlock(&its->cmd_lock); > + return ret; > +} > + > #define BASER_INDEX(addr) (((addr) / sizeof(u64)) & 0x7) > static unsigned long vgic_mmio_read_its_baser(struct kvm *kvm, > struct vgic_its *its, > @@ -1317,6 +1345,16 @@ static void vgic_mmio_write_its_ctlr(struct kvm *kvm, struct vgic_its *its, > .its_write = wr, \ > } > > +#define REGISTER_ITS_DESC_UACCESS(off, rd, wr, uwr, length, acc)\ > +{ \ > + .reg_offset = off, \ > + .len = length, \ > + .access_flags = acc, \ > + .its_read = rd, \ > + .its_write = wr, \ > + .uaccess_its_write = uwr, \ > +} > + > static void its_mmio_write_wi(struct kvm *kvm, struct vgic_its *its, > gpa_t addr, unsigned int len, unsigned long val) > { > @@ -1339,8 +1377,9 @@ static struct vgic_register_region its_registers[] = { > REGISTER_ITS_DESC(GITS_CWRITER, > vgic_mmio_read_its_cwriter, vgic_mmio_write_its_cwriter, 8, > VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), > - REGISTER_ITS_DESC(GITS_CREADR, > - vgic_mmio_read_its_creadr, its_mmio_write_wi, 8, > + REGISTER_ITS_DESC_UACCESS(GITS_CREADR, > + vgic_mmio_read_its_creadr, its_mmio_write_wi, > + vgic_mmio_uaccess_write_its_creadr, 8, > VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), > REGISTER_ITS_DESC(GITS_BASER, > vgic_mmio_read_its_baser, vgic_mmio_write_its_baser, 0x40, > -- > 2.5.5 > Otherwise: Reviewed-by: Christoffer Dall <cdall@xxxxxxxxxx>