KVM: s390: pfmf: fix end address calculation
The current calculation is wrong if absolute != real address. Let's just
calculate the start address for 4k frames upfront. Otherwise, the
calculated end address will be wrong, resulting in wrong memory
location/storage keys getting touched.
To keep low-address protection working (using the effective address),
we have to move the check.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.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 c6deed7..bfba983 100644
--- a/arch/s390/kvm/priv.c
+++ b/arch/s390/kvm/priv.c
@@ -682,8 +682,15 @@
start = vcpu->run->s.regs.gprs[reg2] & PAGE_MASK;
start = kvm_s390_logical_to_effective(vcpu, start);
+ if (vcpu->run->s.regs.gprs[reg1] & PFMF_CF) {
+ if (kvm_s390_check_low_addr_prot_real(vcpu, start))
+ return kvm_s390_inject_prog_irq(vcpu, &vcpu->arch.pgm);
+ }
+
switch (vcpu->run->s.regs.gprs[reg1] & PFMF_FSC) {
case 0x00000000:
+ /* only 4k frames specify a real address */
+ start = kvm_s390_real_to_abs(vcpu, start);
end = (start + (1UL << 12)) & ~((1UL << 12) - 1);
break;
case 0x00001000:
@@ -701,20 +708,11 @@
return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
}
- if (vcpu->run->s.regs.gprs[reg1] & PFMF_CF) {
- if (kvm_s390_check_low_addr_prot_real(vcpu, start))
- return kvm_s390_inject_prog_irq(vcpu, &vcpu->arch.pgm);
- }
-
while (start < end) {
- unsigned long useraddr, abs_addr;
+ unsigned long useraddr;
/* Translate guest address to host address */
- if ((vcpu->run->s.regs.gprs[reg1] & PFMF_FSC) == 0)
- abs_addr = kvm_s390_real_to_abs(vcpu, start);
- else
- abs_addr = start;
- useraddr = gfn_to_hva(vcpu->kvm, gpa_to_gfn(abs_addr));
+ useraddr = gfn_to_hva(vcpu->kvm, gpa_to_gfn(start));
if (kvm_is_error_hva(useraddr))
return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);