| Message ID | 1458281388-14452-3-git-send-email-Suravee.Suthikulpanit@amd.com |
|---|---|
| State | New |
| Headers | show |
Hi Paolo, On 3/18/16 17:11, Paolo Bonzini wrote: > > On 18/03/2016 07:09, Suravee Suthikulpanit wrote: >> >Adding function pointers in struct kvm_x86_ops for processor-specific >> >layer to provide hooks for when KVM initialize and un-initialize VM. > This is not the only thing your patch is doing, and the "other" change > definitely needs a lot more explanation about why you did it and how you > audited the code to ensure that it is safe. > > Paolo > Sorry, for not mentioning this earlier. I am moving the kvm_arch_init_vm() call mainly to go after mutex_init(&kvm->slots_lock) since I am calling the x86_set_memory_region() (which uses slots_lock) in the vm_init() hooks (for AVIC initialization). Lemme re-check if this would be safe for other code. Thanks, Suravee
Hi, On 03/29/2016 05:21 PM, Paolo Bonzini wrote: > > > On 29/03/2016 07:27, Suravee Suthikulpanit wrote: >>> >>>>> Adding function pointers in struct kvm_x86_ops for processor-specific >>>>> layer to provide hooks for when KVM initialize and un-initialize VM. >>> This is not the only thing your patch is doing, and the "other" change >>> definitely needs a lot more explanation about why you did it and how you >>> audited the code to ensure that it is safe. >>> >>> Paolo >>> >> >> Sorry, for not mentioning this earlier. I am moving the >> kvm_arch_init_vm() call mainly to go after mutex_init(&kvm->slots_lock) >> since I am calling the x86_set_memory_region() (which uses slots_lock) >> in the vm_init() hooks (for AVIC initialization). >> >> Lemme re-check if this would be safe for other code. > > No problem. In the meanwhile a patch got in ("KVM: fix spin_lock_init > order on x86") that should help you. > > Thanks, > > Paolo > Right.... that's just what I need :) I'll re-base to the latest tip then. Thanks, Suravee
Hi Paolo, On 3/29/16 18:47, Suravee Suthikulpanit wrote: > Hi, > > On 03/29/2016 05:21 PM, Paolo Bonzini wrote: >> >> >> On 29/03/2016 07:27, Suravee Suthikulpanit wrote: >>>> >>>>>> Adding function pointers in struct kvm_x86_ops for processor-specific >>>>>> layer to provide hooks for when KVM initialize and un-initialize VM. >>>> This is not the only thing your patch is doing, and the "other" change >>>> definitely needs a lot more explanation about why you did it and how >>>> you >>>> audited the code to ensure that it is safe. >>>> >>>> Paolo >>>> >>> >>> Sorry, for not mentioning this earlier. I am moving the >>> kvm_arch_init_vm() call mainly to go after mutex_init(&kvm->slots_lock) >>> since I am calling the x86_set_memory_region() (which uses slots_lock) >>> in the vm_init() hooks (for AVIC initialization). >>> >>> Lemme re-check if this would be safe for other code. >> >> No problem. In the meanwhile a patch got in ("KVM: fix spin_lock_init >> order on x86") that should help you. >> >> Thanks, >> >> Paolo >> > > Right.... that's just what I need :) I'll re-base to the latest tip then. Actually, in the file virt/kvm/kvm_main.c, I still need to move the kvm_arch_init_vm() to some place after the call to kvm_alloc_memslots() since I am calling x86_set_memory_region() in the vm_init hook. r = -ENOMEM; for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) { kvm->memslots[i] = kvm_alloc_memslots(); if (!kvm->memslots[i]) goto out_err_no_srcu; } if (init_srcu_struct(&kvm->srcu)) goto out_err_no_srcu; if (init_srcu_struct(&kvm->irq_srcu)) goto out_err_no_irq_srcu; for (i = 0; i < KVM_NR_BUSES; i++) { kvm->buses[i] = kzalloc(sizeof(struct kvm_io_bus), GFP_KERNEL); if (!kvm->buses[i]) goto out_err; } //HERE r = kvm_arch_init_vm(kvm, type); if (r) goto out_err; Do you think that would be a problem? Thanks, Suravee
Hi Paolo, On 3/30/16 19:07, Paolo Bonzini wrote: > > > On 30/03/2016 12:00, Suravee Suthikulpanit wrote: >> Hi Paolo, >> >> On 3/29/16 18:47, Suravee Suthikulpanit wrote: >>> Hi, >>> >>> On 03/29/2016 05:21 PM, Paolo Bonzini wrote: >>>> >>>> >>>> On 29/03/2016 07:27, Suravee Suthikulpanit wrote: >>>>>> >>>>>>>> Adding function pointers in struct kvm_x86_ops for >>>>>>>> processor-specific >>>>>>>> layer to provide hooks for when KVM initialize and un-initialize VM. >>>>>> This is not the only thing your patch is doing, and the "other" change >>>>>> definitely needs a lot more explanation about why you did it and how >>>>>> you >>>>>> audited the code to ensure that it is safe. >>>>>> >>>>>> Paolo >>>>>> >>>>> >>>>> Sorry, for not mentioning this earlier. I am moving the >>>>> kvm_arch_init_vm() call mainly to go after mutex_init(&kvm->slots_lock) >>>>> since I am calling the x86_set_memory_region() (which uses slots_lock) >>>>> in the vm_init() hooks (for AVIC initialization). >>>>> >>>>> Lemme re-check if this would be safe for other code. >>>> >>>> No problem. In the meanwhile a patch got in ("KVM: fix spin_lock_init >>>> order on x86") that should help you. >>>> >>>> Thanks, >>>> >>>> Paolo >>>> >>> >>> Right.... that's just what I need :) I'll re-base to the latest tip then. >> >> Actually, in the file virt/kvm/kvm_main.c, I still need to move the >> kvm_arch_init_vm() to some place after the call to kvm_alloc_memslots() >> since I am calling x86_set_memory_region() in the vm_init hook. >> >> r = -ENOMEM; >> for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) { >> kvm->memslots[i] = kvm_alloc_memslots(); >> if (!kvm->memslots[i]) >> goto out_err_no_srcu; >> } >> >> if (init_srcu_struct(&kvm->srcu)) >> goto out_err_no_srcu; >> if (init_srcu_struct(&kvm->irq_srcu)) >> goto out_err_no_irq_srcu; >> for (i = 0; i < KVM_NR_BUSES; i++) { >> kvm->buses[i] = kzalloc(sizeof(struct kvm_io_bus), >> GFP_KERNEL); >> if (!kvm->buses[i]) >> goto out_err; >> } >> //HERE >> r = kvm_arch_init_vm(kvm, type); >> if (r) >> goto out_err; >> >> Do you think that would be a problem? > > Can you delay that to after the creation of the first VCPU? Sure, I can. That's what I was doing originally before we introduce the vm_init hook. I just thought that this would make a nice place. > Allocating AVIC data structures is not required if userspace has not > called KVM_CREATE_IRQCHIP or enabled KVM_CAP_SPLIT_IRQCHIP. > > Paolo > Okay. Thanks, Suravee
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 44adbb8..4b0dd0f 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -828,6 +828,9 @@ struct kvm_x86_ops { bool (*cpu_has_high_real_mode_segbase)(void); void (*cpuid_update)(struct kvm_vcpu *vcpu); + int (*vm_init)(struct kvm *kvm); + void (*vm_uninit)(struct kvm *kvm); + /* Create, but do not attach this VCPU */ struct kvm_vcpu *(*vcpu_create)(struct kvm *kvm, unsigned id); void (*vcpu_free)(struct kvm_vcpu *vcpu); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 429c3f5..4d2961d 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -7700,6 +7700,8 @@ void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) { + int ret = 0; + if (type) return -EINVAL; @@ -7724,7 +7726,10 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) INIT_DELAYED_WORK(&kvm->arch.kvmclock_update_work, kvmclock_update_fn); INIT_DELAYED_WORK(&kvm->arch.kvmclock_sync_work, kvmclock_sync_fn); - return 0; + if (kvm_x86_ops->vm_init) + ret = kvm_x86_ops->vm_init(kvm); + + return ret; } static void kvm_unload_vcpu_mmu(struct kvm_vcpu *vcpu) @@ -7751,6 +7756,9 @@ static void kvm_free_vcpus(struct kvm *kvm) kvm_for_each_vcpu(i, vcpu, kvm) kvm_arch_vcpu_free(vcpu); + if (kvm_x86_ops->vm_uninit) + kvm_x86_ops->vm_uninit(kvm); + mutex_lock(&kvm->lock); for (i = 0; i < atomic_read(&kvm->online_vcpus); i++) kvm->vcpus[i] = NULL; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 1ca0258..5460325 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -536,10 +536,6 @@ static struct kvm *kvm_create_vm(unsigned long type) if (!kvm) return ERR_PTR(-ENOMEM); - r = kvm_arch_init_vm(kvm, type); - if (r) - goto out_err_no_disable; - r = hardware_enable_all(); if (r) goto out_err_no_disable; @@ -578,6 +574,10 @@ static struct kvm *kvm_create_vm(unsigned long type) atomic_set(&kvm->users_count, 1); INIT_LIST_HEAD(&kvm->devices); + r = kvm_arch_init_vm(kvm, type); + if (r) + goto out_err; + r = kvm_init_mmu_notifier(kvm); if (r) goto out_err;
Adding function pointers in struct kvm_x86_ops for processor-specific layer to provide hooks for when KVM initialize and un-initialize VM. Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> --- arch/x86/include/asm/kvm_host.h | 3 +++ arch/x86/kvm/x86.c | 10 +++++++++- virt/kvm/kvm_main.c | 8 ++++---- 3 files changed, 16 insertions(+), 5 deletions(-) -- 1.9.1