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Peter Anvin" , Tony Krowiak , Halil Pasic , Harald Freudenberger , Holger Dengler , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Alex Williamson , Matthew Rosato , Farhan Ali , Eric Farman , Claudio Imbrenda , Janosch Frank Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, Jason Gunthorpe References: <20260812-vfio-v1-1-5cfe0b1fa4e7@linux.ibm.com> Content-Language: en-US From: "Jason J. Herne" In-Reply-To: <20260812-vfio-v1-1-5cfe0b1fa4e7@linux.ibm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Authority-Analysis: v=2.4 cv=TfimcxQh c=1 sm=1 tr=0 ts=6a8c53ef cx=c_pps a=5BHTudwdYE3Te8bg5FgnPg==:117 a=5BHTudwdYE3Te8bg5FgnPg==:17 a=IkcTkHD0fZMA:10 a=Sv0fKeRqtYgA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=V8glGbnc2Ofi9Qvn3v5h:22 a=VnNF1IyMAAAA:8 a=q4V7ugTeKHCNkP7_hREA:9 a=QEXdDO2ut3YA:10 X-Proofpoint-Spam-Info: AW1haW4tMjYwODI0MDExOCBTYWx0ZWRfX4m5m08DmkbiX gbMU4QsKK1cEalTNwAq4gZLosj4RCSndbRN6pnF/M54xTngLe2s4AYQVxB7vHQG7yn+/bKigdhC dH5TGSWSmhBAtxkRspQaJS8B6+ZBebo= X-Proofpoint-GUID: G53-uqxfYbz00oQYLLfDZ1HnxDcd7Frq X-Proofpoint-ORIG-GUID: 77H8t3_eqQ7HFMsIA0_yR1OfHczPiFnx X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwODI0MDExOCBTYWx0ZWRfXxyKrNOqzoY2R t0WGlJA0s7/tkKqu5dzebG7fKIo4z3yUxFzvoEryqFv0zTWQlLnUchkC+MFciIej/BkB5wJXY7b 0AdCTBEvEDS24LzXgoms5wMHjZkk5GQIxU2udF6L6WVoImW5CvnJU67bANpQkgBBG6twTAm8lLk vdaVdyQLah4XHYb+ECmeArPpL5ZpDzaEVZR9Qb3wPIReYrIbPDuBC6LxhBP/r11yL4l9VQ2VxcT 3Pv7DhJLwALOuGrs4egskNDBKinqzP6FOXDslb5gq4862+MA3soeEEKF9KLpxfh0oXPgmhCE0DY BP82FbJZq9ovSFTGed9YReeNaXPeiyiQR5AvPviARq6WHpLr52DNDO4W1pqw1e3wcFib8VyGrPf tBwhmRjADZEJaytU5EE36Rok95j8JsAcWPEvRUvB3XcvzVvaby+EcR4uFA3Ue/l81V4qaDZEkmS TXCK+rkXkbE15SbGK9w== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1176,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-08-24_04,2026-08-24_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 spamscore=0 bulkscore=0 malwarescore=0 priorityscore=1501 lowpriorityscore=0 clxscore=1011 phishscore=0 impostorscore=0 adultscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2608240118 On 8/12/26 2:55 PM, Steffen Eiden wrote: > ... > diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c > index 99a0efd999ef..42d331c84e66 100644 > --- a/drivers/s390/crypto/vfio_ap_ops.c > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -1817,17 +1817,27 @@ static const struct attribute_group *vfio_ap_mdev_attr_groups[] = { > > /** > * vfio_ap_mdev_set_kvm - sets all data for @matrix_mdev that are needed > - * to manage AP resources for the guest whose state is represented by @kvm > + * to manage AP resources for the guest whose state is represented by > + * @kvm_file > * > * @matrix_mdev: a mediated matrix device > - * @kvm: reference to KVM instance > + * @kvm_file: the KVM VM file this vfio device is associated with > * > - * Return: 0 if no other mediated matrix device has a reference to @kvm; > + * Return: 0 if no other mediated matrix device has a reference to the VM; > * otherwise, returns an -EPERM. > */ > static int vfio_ap_mdev_set_kvm(struct ap_matrix_mdev *matrix_mdev, > - struct kvm *kvm) > + struct file *kvm_file) > { > + struct kvm *kvm; > + > + if (!kvm_file) > + return -ENOENT; > + > + kvm = kvm_file->private_data; > + if (!kvm) > + return -ENOENT; > + > if (kvm->arch.crypto.crycbd) { > get_update_locks_for_kvm(kvm); > if (kvm->arch.crypto.pqap_hook) { > @@ -1836,7 +1846,6 @@ static int vfio_ap_mdev_set_kvm(struct ap_matrix_mdev *matrix_mdev, > } > kvm->arch.crypto.pqap_hook = &matrix_mdev->pqap_hook; > > - kvm_get_kvm(kvm); > matrix_mdev->kvm = kvm; > vfio_ap_mdev_update_guest_apcb(matrix_mdev); > release_update_locks_for_kvm(kvm); > @@ -1889,7 +1898,6 @@ static void vfio_ap_mdev_unset_kvm(struct ap_matrix_mdev *matrix_mdev) > matrix_mdev->kvm = NULL; > > release_update_locks_for_kvm(kvm); > - kvm_put_kvm(kvm); > } > } Reviewed-by: Jason J. Herne