From 189e7d876e48d7c791fe1c9c01516f70f5621a9f Mon Sep 17 00:00:00 2001 From: Matthew Rosato Date: Tue, 20 Sep 2022 15:30:25 -0400 Subject: [PATCH] KVM: s390: pci: register pci hooks without interpretation The kvm registration hooks must be registered even if the facilities necessary for zPCI interpretation are unavailable, as vfio-pci-zdev will expect to use the hooks regardless. This fixes an issue where vfio-pci-zdev will fail its open function because of a missing kvm_register when running on hardware that does not support zPCI interpretation. Fixes: ca922fecda6c ("KVM: s390: pci: Hook to access KVM lowlevel from VFIO") Signed-off-by: Matthew Rosato Reviewed-by: Pierre Morel Link: https://lore.kernel.org/r/20220920193025.135655-1-mjrosato@linux.ibm.com Message-Id: <20220920193025.135655-1-mjrosato@linux.ibm.com> Signed-off-by: Janosch Frank --- arch/s390/kvm/kvm-s390.c | 4 ++-- arch/s390/kvm/pci.c | 14 +++++++++++--- 2 files changed, 13 insertions(+), 5 deletions(-) diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index edfd4bbd0cbae..b7ef0b71014df 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -505,7 +505,7 @@ int kvm_arch_init(void *opaque) goto out; } - if (kvm_s390_pci_interp_allowed()) { + if (IS_ENABLED(CONFIG_VFIO_PCI_ZDEV_KVM)) { rc = kvm_s390_pci_init(); if (rc) { pr_err("Unable to allocate AIFT for PCI\n"); @@ -527,7 +527,7 @@ out: void kvm_arch_exit(void) { kvm_s390_gib_destroy(); - if (kvm_s390_pci_interp_allowed()) + if (IS_ENABLED(CONFIG_VFIO_PCI_ZDEV_KVM)) kvm_s390_pci_exit(); debug_unregister(kvm_s390_dbf); debug_unregister(kvm_s390_dbf_uv); diff --git a/arch/s390/kvm/pci.c b/arch/s390/kvm/pci.c index 90aaba80696a4..c50c1645c0aec 100644 --- a/arch/s390/kvm/pci.c +++ b/arch/s390/kvm/pci.c @@ -672,23 +672,31 @@ out: int kvm_s390_pci_init(void) { + zpci_kvm_hook.kvm_register = kvm_s390_pci_register_kvm; + zpci_kvm_hook.kvm_unregister = kvm_s390_pci_unregister_kvm; + + if (!kvm_s390_pci_interp_allowed()) + return 0; + aift = kzalloc(sizeof(struct zpci_aift), GFP_KERNEL); if (!aift) return -ENOMEM; spin_lock_init(&aift->gait_lock); mutex_init(&aift->aift_lock); - zpci_kvm_hook.kvm_register = kvm_s390_pci_register_kvm; - zpci_kvm_hook.kvm_unregister = kvm_s390_pci_unregister_kvm; return 0; } void kvm_s390_pci_exit(void) { - mutex_destroy(&aift->aift_lock); zpci_kvm_hook.kvm_register = NULL; zpci_kvm_hook.kvm_unregister = NULL; + if (!kvm_s390_pci_interp_allowed()) + return; + + mutex_destroy(&aift->aift_lock); + kfree(aift); } -- 2.30.2