Message ID | 20200130123434.68129-2-frankja@linux.ibm.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | KVM: s390: Add new reset vcpu API | expand |
On 30.01.20 13:34, Janosch Frank wrote: > From: Christian Borntraeger <borntraeger@de.ibm.com> > > The initial CPU reset clobbers the userspace fpc and the store status > ioctl clobbers the guest acrs + fpr. As these calls are only done via > ioctl (and not via vcpu_run), no CPU context is loaded, so we can (and > must) act directly on the sync regs, not on the thread context. > > Cc: stable@kernel.org > Fixes: e1788bb995be ("KVM: s390: handle floating point registers in the run ioctl not in vcpu_put/load") > Fixes: 31d8b8d41a7e ("KVM: s390: handle access registers in the run ioctl not in vcpu_put/load") > Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> > --- > arch/s390/kvm/kvm-s390.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c > index c059b86aacd4..328dee666b24 100644 > --- a/arch/s390/kvm/kvm-s390.c > +++ b/arch/s390/kvm/kvm-s390.c > @@ -2824,8 +2824,7 @@ static void kvm_s390_vcpu_initial_reset(struct kvm_vcpu *vcpu) > vcpu->arch.sie_block->gcr[14] = CR14_UNUSED_32 | > CR14_UNUSED_33 | > CR14_EXTERNAL_DAMAGE_SUBMASK; > - /* make sure the new fpc will be lazily loaded */ > - save_fpu_regs(); > + vcpu->run->s.regs.fpc = 0; > current->thread.fpu.fpc = 0; > vcpu->arch.sie_block->gbea = 1; > vcpu->arch.sie_block->pp = 0; > @@ -4343,7 +4342,7 @@ long kvm_arch_vcpu_ioctl(struct file *filp, > switch (ioctl) { > case KVM_S390_STORE_STATUS: > idx = srcu_read_lock(&vcpu->kvm->srcu); > - r = kvm_s390_vcpu_store_status(vcpu, arg); > + r = kvm_s390_store_status_unloaded(vcpu, arg); > srcu_read_unlock(&vcpu->kvm->srcu, idx); > break; > case KVM_S390_SET_INITIAL_PSW: { > Reviewed-by: David Hildenbrand <david@redhat.com>
On Thu, 30 Jan 2020 07:34:29 -0500 Janosch Frank <frankja@linux.ibm.com> wrote: > From: Christian Borntraeger <borntraeger@de.ibm.com> > > The initial CPU reset clobbers the userspace fpc and the store status > ioctl clobbers the guest acrs + fpr. As these calls are only done via > ioctl (and not via vcpu_run), no CPU context is loaded, so we can (and > must) act directly on the sync regs, not on the thread context. > > Cc: stable@kernel.org > Fixes: e1788bb995be ("KVM: s390: handle floating point registers in the run ioctl not in vcpu_put/load") > Fixes: 31d8b8d41a7e ("KVM: s390: handle access registers in the run ioctl not in vcpu_put/load") > Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Add your s-o-b? > --- > arch/s390/kvm/kvm-s390.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) Reviewed-by: Cornelia Huck <cohuck@redhat.com>
On 30.01.20 13:34, Janosch Frank wrote: > From: Christian Borntraeger <borntraeger@de.ibm.com> > > The initial CPU reset clobbers the userspace fpc and the store status > ioctl clobbers the guest acrs + fpr. As these calls are only done via > ioctl (and not via vcpu_run), no CPU context is loaded, so we can (and > must) act directly on the sync regs, not on the thread context. > > Cc: stable@kernel.org > Fixes: e1788bb995be ("KVM: s390: handle floating point registers in the run ioctl not in vcpu_put/load") > Fixes: 31d8b8d41a7e ("KVM: s390: handle access registers in the run ioctl not in vcpu_put/load") > Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> > --- > arch/s390/kvm/kvm-s390.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c > index c059b86aacd4..328dee666b24 100644 > --- a/arch/s390/kvm/kvm-s390.c > +++ b/arch/s390/kvm/kvm-s390.c > @@ -2824,8 +2824,7 @@ static void kvm_s390_vcpu_initial_reset(struct kvm_vcpu *vcpu) > vcpu->arch.sie_block->gcr[14] = CR14_UNUSED_32 | > CR14_UNUSED_33 | > CR14_EXTERNAL_DAMAGE_SUBMASK; > - /* make sure the new fpc will be lazily loaded */ > - save_fpu_regs(); > + vcpu->run->s.regs.fpc = 0; > current->thread.fpu.fpc = 0; this needs to go out here as well. > vcpu->arch.sie_block->gbea = 1; > vcpu->arch.sie_block->pp = 0; > @@ -4343,7 +4342,7 @@ long kvm_arch_vcpu_ioctl(struct file *filp, > switch (ioctl) { > case KVM_S390_STORE_STATUS: > idx = srcu_read_lock(&vcpu->kvm->srcu); > - r = kvm_s390_vcpu_store_status(vcpu, arg); > + r = kvm_s390_store_status_unloaded(vcpu, arg); > srcu_read_unlock(&vcpu->kvm->srcu, idx); > break; > case KVM_S390_SET_INITIAL_PSW: { >
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index c059b86aacd4..328dee666b24 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -2824,8 +2824,7 @@ static void kvm_s390_vcpu_initial_reset(struct kvm_vcpu *vcpu) vcpu->arch.sie_block->gcr[14] = CR14_UNUSED_32 | CR14_UNUSED_33 | CR14_EXTERNAL_DAMAGE_SUBMASK; - /* make sure the new fpc will be lazily loaded */ - save_fpu_regs(); + vcpu->run->s.regs.fpc = 0; current->thread.fpu.fpc = 0; vcpu->arch.sie_block->gbea = 1; vcpu->arch.sie_block->pp = 0; @@ -4343,7 +4342,7 @@ long kvm_arch_vcpu_ioctl(struct file *filp, switch (ioctl) { case KVM_S390_STORE_STATUS: idx = srcu_read_lock(&vcpu->kvm->srcu); - r = kvm_s390_vcpu_store_status(vcpu, arg); + r = kvm_s390_store_status_unloaded(vcpu, arg); srcu_read_unlock(&vcpu->kvm->srcu, idx); break; case KVM_S390_SET_INITIAL_PSW: {