Messages in this thread | | | Subject | Re: [PATCH v3 7/9] s390: ap: implement PAPQ AQIC interception in kernel | From | Pierre Morel <> | Date | Thu, 21 Feb 2019 13:50:26 +0100 |
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On 20/02/2019 12:54, Halil Pasic wrote: > On Thu, 14 Feb 2019 14:51:07 +0100 > Pierre Morel <pmorel@linux.ibm.com> wrote: > >> We register the AP PQAP instruction hook during the open >> of the mediated device. And unregister it on release. >> >> In the AP PQAP instruction hook, if we receive a demand to >> enable IRQs, >> - we retrieve the vfio_ap_queue based on the APQN we receive >> in REG1, >> - we retrieve the page of the guest address, (NIB), from >> register REG2 >> - we the mediated device to use the VFIO pinning infratrsucture >> to pin the page of the guest address, >> - we retrieve the pointer to KVM to register the guest ISC >> and retrieve the host ISC >> - finaly we activate GISA >> >> If we receive a demand to disable IRQs, >> - we deactivate GISA >> - unregister from the GIB >> - unping the NIB >> >> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> >> --- > > [..] > >> +static int handle_pqap(struct kvm_vcpu *vcpu) >> +{ >> + uint64_t status; >> + uint16_t apqn; >> + struct vfio_ap_queue *q; >> + struct ap_queue_status qstatus = {}; >> + struct ap_matrix_mdev *matrix_mdev; >> + >> + /* If we do not use the AIV facility just go to userland */ >> + if (!(vcpu->arch.sie_block->eca & ECA_AIV)) >> + return -EOPNOTSUPP; >> + >> + apqn = vcpu->run->s.regs.gprs[0] & 0xffff; >> + q = vfio_ap_get_queue(apqn); >> + if (!q) { >> + qstatus.response_code = AP_RESPONSE_Q_NOT_AVAIL; >> + goto out; >> + } >> + >> + /* Check if the queue is associated with a guest matrix */ >> + matrix_mdev = q->matrix; >> + if (!matrix_mdev || !matrix_mdev->kvm) { >> + qstatus.response_code = AP_RESPONSE_DECONFIGURED; >> + goto out; >> + } >> + >> + status = vcpu->run->s.regs.gprs[1]; >> + >> + /* If IR bit(16) is set we enable the interrupt */ >> + if ((status >> (63 - 16)) & 0x01) { >> + q->isc = status & 0x07; >> + q->nib = vcpu->run->s.regs.gprs[2]; > > Careful! You may already have q->nib set (may or may not be a 0x07 > scenario). You should unpin the old nib if set interruption controls > works out, if we get 0x07 response then you unpin the new one.
You are right. We already had this discussion and the corrected patch. It seems I misunderstood what we wanted to do by sending this patch series out.
I will make this right.
regards, Pierre
-- Pierre Morel Linux/KVM/QEMU in Böblingen - Germany
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