| Message ID | 1499352359-5401-1-git-send-email-borntraeger@de.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 07/06/2017 04:45 PM, Christian Borntraeger wrote: > we access the memslots array via srcu. Mark it as such and > use the right access functions also for the freeing of > memory slots. > > Found by sparse: > ./include/linux/kvm_host.h:565:16: error: incompatible types in > comparison expression (different address spaces) > > Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> > --- > include/linux/kvm_host.h | 2 +- > virt/kvm/kvm_main.c | 4 ++-- > 2 files changed, 3 insertions(+), 3 deletions(-) > > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h > index bcd37b8..7c32905 100644 > --- a/include/linux/kvm_host.h > +++ b/include/linux/kvm_host.h > @@ -390,7 +390,7 @@ struct kvm { > spinlock_t mmu_lock; > struct mutex slots_lock; > struct mm_struct *mm; /* userspace tied to this vm */ > - struct kvm_memslots *memslots[KVM_ADDRESS_SPACE_NUM]; > + struct kvm_memslots __rcu *memslots[KVM_ADDRESS_SPACE_NUM]; > struct kvm_vcpu *vcpus[KVM_MAX_VCPUS]; > > /* > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index fc2d583..d4418fa 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -707,7 +707,7 @@ static struct kvm *kvm_create_vm(unsigned long type) > for (i = 0; i < KVM_NR_BUSES; i++) > kfree(kvm->buses[i]); > for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) > - kvm_free_memslots(kvm, kvm->memslots[i]); > + kvm_free_memslots(kvm, rcu_access_pointer(kvm->memslots[i])); should these rather be rcu_dereference_protected ? > kvm_arch_free_vm(kvm); > mmdrop(current->mm); > return ERR_PTR(r); > @@ -753,7 +753,7 @@ static void kvm_destroy_vm(struct kvm *kvm) > kvm_arch_destroy_vm(kvm); > kvm_destroy_devices(kvm); > for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) > - kvm_free_memslots(kvm, kvm->memslots[i]); > + kvm_free_memslots(kvm, rcu_access_pointer(kvm->memslots[i])); > cleanup_srcu_struct(&kvm->irq_srcu); > cleanup_srcu_struct(&kvm->srcu); > kvm_arch_free_vm(kvm); >
On 06/07/2017 16:55, Christian Borntraeger wrote: > On 07/06/2017 04:45 PM, Christian Borntraeger wrote: >> we access the memslots array via srcu. Mark it as such and >> use the right access functions also for the freeing of >> memory slots. >> >> Found by sparse: >> ./include/linux/kvm_host.h:565:16: error: incompatible types in >> comparison expression (different address spaces) >> >> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> >> --- >> include/linux/kvm_host.h | 2 +- >> virt/kvm/kvm_main.c | 4 ++-- >> 2 files changed, 3 insertions(+), 3 deletions(-) >> >> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h >> index bcd37b8..7c32905 100644 >> --- a/include/linux/kvm_host.h >> +++ b/include/linux/kvm_host.h >> @@ -390,7 +390,7 @@ struct kvm { >> spinlock_t mmu_lock; >> struct mutex slots_lock; >> struct mm_struct *mm; /* userspace tied to this vm */ >> - struct kvm_memslots *memslots[KVM_ADDRESS_SPACE_NUM]; >> + struct kvm_memslots __rcu *memslots[KVM_ADDRESS_SPACE_NUM]; >> struct kvm_vcpu *vcpus[KVM_MAX_VCPUS]; >> >> /* >> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c >> index fc2d583..d4418fa 100644 >> --- a/virt/kvm/kvm_main.c >> +++ b/virt/kvm/kvm_main.c >> @@ -707,7 +707,7 @@ static struct kvm *kvm_create_vm(unsigned long type) >> for (i = 0; i < KVM_NR_BUSES; i++) >> kfree(kvm->buses[i]); >> for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) >> - kvm_free_memslots(kvm, kvm->memslots[i]); >> + kvm_free_memslots(kvm, rcu_access_pointer(kvm->memslots[i])); > > should these rather be rcu_dereference_protected ? Yes, I think so. Paolo >> kvm_arch_free_vm(kvm); >> mmdrop(current->mm); >> return ERR_PTR(r); >> @@ -753,7 +753,7 @@ static void kvm_destroy_vm(struct kvm *kvm) >> kvm_arch_destroy_vm(kvm); >> kvm_destroy_devices(kvm); >> for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) >> - kvm_free_memslots(kvm, kvm->memslots[i]); >> + kvm_free_memslots(kvm, rcu_access_pointer(kvm->memslots[i])); >> cleanup_srcu_struct(&kvm->irq_srcu); >> cleanup_srcu_struct(&kvm->srcu); >> kvm_arch_free_vm(kvm); >> >
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index bcd37b8..7c32905 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -390,7 +390,7 @@ struct kvm { spinlock_t mmu_lock; struct mutex slots_lock; struct mm_struct *mm; /* userspace tied to this vm */ - struct kvm_memslots *memslots[KVM_ADDRESS_SPACE_NUM]; + struct kvm_memslots __rcu *memslots[KVM_ADDRESS_SPACE_NUM]; struct kvm_vcpu *vcpus[KVM_MAX_VCPUS]; /* diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index fc2d583..d4418fa 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -707,7 +707,7 @@ static struct kvm *kvm_create_vm(unsigned long type) for (i = 0; i < KVM_NR_BUSES; i++) kfree(kvm->buses[i]); for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) - kvm_free_memslots(kvm, kvm->memslots[i]); + kvm_free_memslots(kvm, rcu_access_pointer(kvm->memslots[i])); kvm_arch_free_vm(kvm); mmdrop(current->mm); return ERR_PTR(r); @@ -753,7 +753,7 @@ static void kvm_destroy_vm(struct kvm *kvm) kvm_arch_destroy_vm(kvm); kvm_destroy_devices(kvm); for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) - kvm_free_memslots(kvm, kvm->memslots[i]); + kvm_free_memslots(kvm, rcu_access_pointer(kvm->memslots[i])); cleanup_srcu_struct(&kvm->irq_srcu); cleanup_srcu_struct(&kvm->srcu); kvm_arch_free_vm(kvm);
we access the memslots array via srcu. Mark it as such and use the right access functions also for the freeing of memory slots. Found by sparse: ./include/linux/kvm_host.h:565:16: error: incompatible types in comparison expression (different address spaces) Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> --- include/linux/kvm_host.h | 2 +- virt/kvm/kvm_main.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-)