| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <be66fe05-f728-25b8-a786-4e7bf39965d1@linux.ibm.com>
Date: Wed, 7 Nov 2018 23:31:59 +0100
From: Pierre Morel <pmorel@...ux.ibm.com>
To: Tony Krowiak <akrowiak@...ux.ibm.com>, borntraeger@...ibm.com
Cc: alex.williamson@...hat.com, cohuck@...hat.com,
linux-kernel@...r.kernel.org, linux-s390@...r.kernel.org,
kvm@...r.kernel.org, frankja@...ux.ibm.com, pasic@...ux.ibm.com,
david@...hat.com, schwidefsky@...ibm.com,
heiko.carstens@...ibm.com, freude@...ux.ibm.com, mimu@...ux.ibm.com
Subject: Re: [PATCH v1 4/7] vfio: ap: AP Queue Interrupt Control VFIO ioctl
calls
On 06/11/2018 21:21, Tony Krowiak wrote:
> On 10/31/18 2:12 PM, Pierre Morel wrote:
>> This is the implementation of the VFIO ioctl calls to handle
>> the AQIC interception and use GISA to handle interrupts.
>>
>> Signed-off-by: Pierre Morel <pmorel@...ux.ibm.com>
>> ---
>> drivers/s390/crypto/vfio_ap_ops.c | 95 +++++++++++++++++++++++++++++++
>> 1 file changed, 95 insertions(+)
>>
>> diff --git a/drivers/s390/crypto/vfio_ap_ops.c
>> b/drivers/s390/crypto/vfio_ap_ops.c
>> index 272ef427dcc0..f68102163bf4 100644
>> --- a/drivers/s390/crypto/vfio_ap_ops.c
>> +++ b/drivers/s390/crypto/vfio_ap_ops.c
>> @@ -895,12 +895,107 @@ static int
>> vfio_ap_mdev_get_device_info(unsigned long arg)
>> return copy_to_user((void __user *)arg, &info, minsz);
>> }
>> +static int ap_ioctl_setirq(struct ap_matrix_mdev *matrix_mdev,
>
> In keeping with the other function names in this file, how about
> naming this function vfio_ap_mdev_setirq???
OK, agreed.
>
>> + struct vfio_ap_aqic *parm)
>> +{
>> + struct aqic_gisa aqic_gisa = reg2aqic(0);
>> + struct kvm_s390_gisa *gisa = matrix_mdev->kvm->arch.gisa;
>> + struct ap_status ap_status = reg2status(0);
>> + unsigned long p;
>> + int ret = -1;
>> + int apqn;
>> + uint32_t gd;
>> +
>> + 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;
>
> Can't you get this value from parm? I don't see any relationship
> between the mdev device and gisc, why store it there?
The idea is that we may want to report this value to the admin or as
debug information, so I wanted to keep track of it.
>
>> + aqic_gisa.isc = GAL_ISC;
>> + aqic_gisa.ir = 1;
>> + aqic_gisa.gisao = gisa->next_alert >> 4;
>> +
>> + p = (unsigned long) page_address(matrix_mdev->map->page);
>> + p += (matrix_mdev->map->guest_addr & 0x0fff);
>> +
>> + ret = ap_host_aqic((uint64_t)apqn, aqic2reg(aqic_gisa), p);
>> + parm->status = ret;
>> +
>> + ap_status = reg2status(ret);
>> + return (ap_status.rc) ? -EIO : 0;
>> +}
>> +
>> +static int ap_ioctl_clrirq(struct ap_matrix_mdev *matrix_mdev,
>> + struct vfio_ap_aqic *parm)
>
> In keeping with the other function names in this file, how about
> naming this function vfio_ap_mdev_clrirq, or better yet,
> vfio_ap_mdev_clear_irq???
agreed too.
>
>> +{
>> + struct aqic_gisa aqic_gisa = reg2aqic(0);
>> + struct ap_status ap_status = reg2status(0) > + int apqn;
>> + int retval;
>> + uint32_t gd;
>> +
>> + apqn = (int)(parm->cmd & 0xffff);
>> +
>> + gd = matrix_mdev->kvm->vcpus[0]->arch.sie_block->gd;
>> + if (gd & 0x01)
>> + aqic_gisa.f = 1;
>> + aqic_gisa.ir = 0;
>> +
>> + retval = ap_host_aqic((uint64_t)apqn, aqic2reg(aqic_gisa), 0);
>> + parm->status = retval;
>> +
>> + ap_status = reg2status(retval);
>> + return (ap_status.rc) ? -EIO : 0;
>> +}
>> +
>> static ssize_t vfio_ap_mdev_ioctl(struct mdev_device *mdev,
>> unsigned int cmd, unsigned long arg)
>> {
>> int ret;
>> + struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev);
>> + struct s390_io_adapter *adapter;
>> + struct vfio_ap_aqic parm;
>> + struct s390_map_info *map;
>> + int apqn, found = 0;
>> switch (cmd) {
>> + case VFIO_AP_SET_IRQ:
>> + if (copy_from_user(&parm, (void __user *)arg, sizeof(parm)))
>> + return -EFAULT;
>> + apqn = (int)(parm.cmd & 0xffff);
>> + parm.status &= 0x00000000ffffffffUL;
>> + matrix_mdev->gisc = parm.status & 0x07;
>
> It seems that the only reason for the 'gisc' field in matrix_mdev
> is to pass the value to the ap_ioctl_setirq() function. Since the
> gisc has nothing to do with the mdev device and the 'parm' is being
> passed to ap_ioctl_setirq(), why not just eliminate the
> matrix_mdev->gisc field and get it from the 'parm' parameter in
> ap_ioctl_setirq()?
OK, seems better.
>
>> + /* find the adapter */ap_ioctl_setirq()
>> + adapter = matrix_mdev->kvm->arch.adapters[parm.adapter_id];
>> + if (!adapter)
>> + return -ENOENT;
>> + down_write(&adapter->maps_lock);
>> + list_for_each_entry(map, &adapter->maps, list) {
>> + if (map->guest_addr == parm.nib) {
>> + found = 1;
>> + break;
>> + }
>> + }
>> + up_write(&adapter->maps_lock);
>> +
>> + if (!found)
>> + return -EINVAL;
>> +
>> + matrix_mdev->map = map;
>
> See my comment above about matrix_mdev->gisc. Can't we just get rid
> of the matrix_mdev->map field and pass the map into the
> ap_ioctl_setirq() function?
or calculate it from parm... as we give parm as argument to this function
>
>> + ret = ap_ioctl_setirq(matrix_mdev, &parm);
>> + parm.status &= 0x00000000ffffffffUL;
>> + if (copy_to_user((void __user *)arg, &parm, sizeof(parm)))
>> + return -EFAULT;
>> +
>> + break;
>
> IMHO, the case statements should only determine which ioctl is being
> invoked and call the appropriate function to handle it. All of the above
> code could be in an intermediate function called from this case
> statement, thus reducing the case to calling the intermediate function.
OK, I can do so, however I would like to let the __user access here.
>
>> + case VFIO_AP_CLEAR_IRQ:
>> + if (copy_from_user(&parm, (void __user *)arg, sizeof(parm)))
>> + return -EFAULT;
>> + ret = ap_ioctl_clrirq(matrix_mdev, &parm);
>> + if (copy_to_user((void __user *)arg, &parm, sizeof(parm)))
>> + return -EFAULT;
>> + break;
>> case VFIO_DEVICE_GET_INFO:
>> ret = vfio_ap_mdev_get_device_info(arg);
>> break;
>>
>
Thanks
Pierre
--
Pierre Morel
Linux/KVM/QEMU in Böblingen - Germany
Powered by blists - more mailing lists