From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pierre Morel Subject: Re: [PATCH v1 6/7] vfio: ap: register guest ISC with GISA and GIB Date: Wed, 7 Nov 2018 23:40:42 +0100 Message-ID: <5a1f9900-e90a-541d-7801-e7fcfd9f48a3@linux.ibm.com> References: <1541009577-29656-1-git-send-email-pmorel@linux.ibm.com> <1541009577-29656-7-git-send-email-pmorel@linux.ibm.com> <382fe325-e12d-8be8-7f30-c3c64bd37505@linux.ibm.com> Reply-To: pmorel@linux.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Cc: alex.williamson@redhat.com, cohuck@redhat.com, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, kvm@vger.kernel.org, frankja@linux.ibm.com, pasic@linux.ibm.com, david@redhat.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, freude@linux.ibm.com, mimu@linux.ibm.com To: Tony Krowiak , borntraeger@de.ibm.com Return-path: In-Reply-To: <382fe325-e12d-8be8-7f30-c3c64bd37505@linux.ibm.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 06/11/2018 21:21, Tony Krowiak wrote: > On 10/31/18 2:12 PM, Pierre Morel wrote: >> Register to the GIB Alert list and retrieve the GAL_ISC >> to pass to the GISA registration. >> >> Unregister on error and when clearing the interrupt. >> >> Signed-off-by: Pierre Morel >> Signed-off-by: Michael Mueller >> --- >>   drivers/s390/crypto/vfio_ap_ops.c | 16 +++++++++++++--- >>   1 file changed, 13 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/s390/crypto/vfio_ap_ops.c >> b/drivers/s390/crypto/vfio_ap_ops.c >> index f68102163bf4..232168797fb8 100644 >> --- a/drivers/s390/crypto/vfio_ap_ops.c >> +++ b/drivers/s390/crypto/vfio_ap_ops.c >> @@ -903,16 +903,20 @@ static int ap_ioctl_setirq(struct ap_matrix_mdev >> *matrix_mdev, >>       struct ap_status ap_status = reg2status(0); >>       unsigned long p; >>       int ret = -1; >> -    int apqn; >> +    int apqn, gal_isc; >>       uint32_t gd; >> +    gal_isc = kvm_s390_gisc_register(matrix_mdev->kvm, >> matrix_mdev->gisc); >> +    if (gal_isc < 0) >> +        return -EIO; >> + >>       apqn = (int)(parm->cmd & 0xffff); >>       gd = matrix_mdev->kvm->vcpus[0]->arch.sie_block->gd; >>       if (gd & 0x01) >>           aqic_gisa.f = 1; >>       aqic_gisa.gisc = matrix_mdev->gisc; >> -    aqic_gisa.isc = GAL_ISC; >> +    aqic_gisa.isc = gal_isc; >>       aqic_gisa.ir = 1; >>       aqic_gisa.gisao = gisa->next_alert >> 4; >> @@ -923,7 +927,11 @@ static int ap_ioctl_setirq(struct ap_matrix_mdev >> *matrix_mdev, >>       parm->status = ret; >>       ap_status = reg2status(ret); >> -    return (ap_status.rc) ? -EIO : 0; >> +    if (ap_status.rc) { >> +        kvm_s390_gisc_unregister(matrix_mdev->kvm, matrix_mdev->gisc); >> +        return -EIO; >> +    } >> +    return 0; >>   } >>   static int ap_ioctl_clrirq(struct ap_matrix_mdev *matrix_mdev, >> @@ -946,6 +954,8 @@ static int ap_ioctl_clrirq(struct ap_matrix_mdev >> *matrix_mdev, >>       parm->status = retval; >>       ap_status = reg2status(retval); >> +    /* unregister the IAM from the GIB anyway! */ >> +    kvm_s390_gisc_unregister(matrix_mdev->kvm, matrix_mdev->gisc); > > The case statement in patch 4 does not set mdev->gisc, so the > presumption here is that VFIO_AP_SET_IRQ has been previously called and > has set the value for matrix_mdev->gisc. Is it possible for > VFIO_AP_CLEAR_IRQ to get invoked without a prior call to right, I will check this. However if the IRQ is not registered there is no problem as we will get an error when unregistering the IRQ and unregistering the gisc 0 which was not registered will fail too. But I think we better check before in case these functions change. > VFIO_AP_SET_IRQ? In any case, shouldn't the GISC value be taken from > bits 61-63 of 'parm'? No this is not possible, the ISC field is not relevant when clearing interrupts. > >>       return (ap_status.rc) ? -EIO : 0; >>   } >> > -- Pierre Morel Linux/KVM/QEMU in Böblingen - Germany