KVM: s390: Fix low-address protection for real addresses

The kvm_s390_check_low_addr_protection() function is used only with real
addresses. According to the POP (the "Low-Address Protection"
paragraph in chapter 3), if the effective address is real or absolute,
the low-address protection procedure should raise a PROTECTION exception
only when the low-address protection is enabled in the control register
0 and the address is low.
This patch removes ASCE checks from the function and renames it to
better reflect its behavior.

Cc: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
This commit is contained in:
Alexander Yarygin 2015-03-03 14:26:14 +03:00 committed by Christian Borntraeger
parent 40f5b735e8
commit dd9e5b7bdb
3 changed files with 9 additions and 8 deletions

View file

@ -697,28 +697,29 @@ int guest_translate_address(struct kvm_vcpu *vcpu, unsigned long gva,
}
/**
* kvm_s390_check_low_addr_protection - check for low-address protection
* @ga: Guest address
* kvm_s390_check_low_addr_prot_real - check for low-address protection
* @gra: Guest real address
*
* Checks whether an address is subject to low-address protection and set
* up vcpu->arch.pgm accordingly if necessary.
*
* Return: 0 if no protection exception, or PGM_PROTECTION if protected.
*/
int kvm_s390_check_low_addr_protection(struct kvm_vcpu *vcpu, unsigned long ga)
int kvm_s390_check_low_addr_prot_real(struct kvm_vcpu *vcpu, unsigned long gra)
{
struct kvm_s390_pgm_info *pgm = &vcpu->arch.pgm;
psw_t *psw = &vcpu->arch.sie_block->gpsw;
struct trans_exc_code_bits *tec_bits;
union ctlreg0 ctlreg0 = {.val = vcpu->arch.sie_block->gcr[0]};
if (!is_low_address(ga) || !low_address_protection_enabled(vcpu))
if (!ctlreg0.lap || !is_low_address(gra))
return 0;
memset(pgm, 0, sizeof(*pgm));
tec_bits = (struct trans_exc_code_bits *)&pgm->trans_exc_code;
tec_bits->fsi = FSI_STORE;
tec_bits->as = psw_bits(*psw).as;
tec_bits->addr = ga >> PAGE_SHIFT;
tec_bits->addr = gra >> PAGE_SHIFT;
pgm->code = PGM_PROTECTION;
return pgm->code;

View file

@ -330,6 +330,6 @@ int read_guest_real(struct kvm_vcpu *vcpu, unsigned long gra, void *data,
void ipte_lock(struct kvm_vcpu *vcpu);
void ipte_unlock(struct kvm_vcpu *vcpu);
int ipte_lock_held(struct kvm_vcpu *vcpu);
int kvm_s390_check_low_addr_protection(struct kvm_vcpu *vcpu, unsigned long ga);
int kvm_s390_check_low_addr_prot_real(struct kvm_vcpu *vcpu, unsigned long gra);
#endif /* __KVM_S390_GACCESS_H */

View file

@ -207,7 +207,7 @@ static int handle_test_block(struct kvm_vcpu *vcpu)
kvm_s390_get_regs_rre(vcpu, NULL, &reg2);
addr = vcpu->run->s.regs.gprs[reg2] & PAGE_MASK;
addr = kvm_s390_logical_to_effective(vcpu, addr);
if (kvm_s390_check_low_addr_protection(vcpu, addr))
if (kvm_s390_check_low_addr_prot_real(vcpu, addr))
return kvm_s390_inject_prog_irq(vcpu, &vcpu->arch.pgm);
addr = kvm_s390_real_to_abs(vcpu, addr);
@ -680,7 +680,7 @@ static int handle_pfmf(struct kvm_vcpu *vcpu)
}
if (vcpu->run->s.regs.gprs[reg1] & PFMF_CF) {
if (kvm_s390_check_low_addr_protection(vcpu, start))
if (kvm_s390_check_low_addr_prot_real(vcpu, start))
return kvm_s390_inject_prog_irq(vcpu, &vcpu->arch.pgm);
}