KVM: s390: Fix pfmf and conditional skey emulation

We should not return with a lock.
We also have to increase the address when we do page clearing.

Fixes: d83705f660a2 ("KVM: s390: Add skey emulation fault handling")
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Message-Id: <20180830081355.59234-1-frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
index d68f10441a164f2c22236adaa143edf6b1d0f7d0..8679bd74d337a583a3dde940d0cef1f427373a4b 100644 (file)
--- a/arch/s390/kvm/priv.c
+++ b/arch/s390/kvm/priv.c
@@ -280,9 +280,11 @@ retry:
                        goto retry;
                }
        }
-       if (rc)
-               return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
        up_read(&current->mm->mmap_sem);
+       if (rc == -EFAULT)
+               return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
+       if (rc < 0)
+               return rc;
        vcpu->run->s.regs.gprs[reg1] &= ~0xff;
        vcpu->run->s.regs.gprs[reg1] |= key;
        return 0;
@@ -324,9 +326,11 @@ retry:
                        goto retry;
                }
        }
-       if (rc < 0)
-               return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
        up_read(&current->mm->mmap_sem);
+       if (rc == -EFAULT)
+               return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
+       if (rc < 0)
+               return rc;
        kvm_s390_set_psw_cc(vcpu, rc);
        return 0;
 }
@@ -390,12 +394,12 @@ static int handle_sske(struct kvm_vcpu *vcpu)
                                              FAULT_FLAG_WRITE, &unlocked);
                        rc = !rc ? -EAGAIN : rc;
                }
+               up_read(&current->mm->mmap_sem);
                if (rc == -EFAULT)
                        return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
-
-               up_read(&current->mm->mmap_sem);
-               if (rc >= 0)
-                       start += PAGE_SIZE;
+               if (rc < 0)
+                       return rc;
+               start += PAGE_SIZE;
        }
 
        if (m3 & (SSKE_MC | SSKE_MR)) {
@@ -1002,13 +1006,15 @@ static int handle_pfmf(struct kvm_vcpu *vcpu)
                                                      FAULT_FLAG_WRITE, &unlocked);
                                rc = !rc ? -EAGAIN : rc;
                        }
+                       up_read(&current->mm->mmap_sem);
                        if (rc == -EFAULT)
                                return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
-
-                       up_read(&current->mm->mmap_sem);
-                       if (rc >= 0)
-                               start += PAGE_SIZE;
+                       if (rc == -EAGAIN)
+                               continue;
+                       if (rc < 0)
+                               return rc;
                }
+               start += PAGE_SIZE;
        }
        if (vcpu->run->s.regs.gprs[reg1] & PFMF_FSC) {
                if (psw_bits(vcpu->arch.sie_block->gpsw).eaba == PSW_BITS_AMODE_64BIT) {