On Fri, 13 Sep 2019 17:26:52 -0400
Tony Krowiak <akrow...@linux.ibm.com> wrote:
> +static void vfio_ap_mdev_get_crycb_matrix(struct ap_matrix_mdev *matrix_mdev)
> +{
> + unsigned long apid, apqi;
> + unsigned long masksz = BITS_TO_LONGS(AP_DEVICES) *
> + sizeof(unsigned long);
> +
> + memset(matrix_mdev->crycb.apm, 0, masksz);
> + memset(matrix_mdev->crycb.apm, 0, masksz);
> + memcpy(matrix_mdev->crycb.adm, matrix_mdev->matrix.adm, masksz);
> +
> + for_each_set_bit_inv(apid, matrix_mdev->matrix.apm,
> + matrix_mdev->matrix.apm_max + 1) {
> + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm,
> + matrix_mdev->matrix.aqm_max + 1) {
> + if (vfio_ap_find_queue(AP_MKQID(apid, apqi))) {
> + if (!test_bit_inv(apid, matrix_mdev->crycb.apm))
> + set_bit_inv(apid,
> + matrix_mdev->crycb.apm);
> + if (!test_bit_inv(apqi, matrix_mdev->crycb.aqm))
> + set_bit_inv(apqi,
> + matrix_mdev->crycb.aqm);
> + }
> + }
> + }
> +}
Even with the discussed typo fixed (zero crycb.aqm) this procedure does
not make sense to me. :(
If in doubt please consider the following example:
matrix_mdev->matrix.apm and matrix_mdev->matrix.aqm have both just bits
0 and 1 set (i.e. first byte 0xC0 the rest of the bytes 0x0). Queues
bound to the vfio_ap driver (0,0), (0,1), (1,0); not bound to vfio_ap is
however (1,1). If I read this correctly this filtering logic would grant
access to (1,1) which seems to contradict with the stated intention.
Regards,
Halil
