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Commit f22166dc authored by Thomas Huth's avatar Thomas Huth Committed by Christian Borntraeger
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KVM: s390: Improved MVPG partial execution handler 



Use the new helper function kvm_arch_fault_in_page() for faulting-in
the guest pages and only inject addressing errors when we've really
hit a bad address (and return other error codes to userspace instead).

Signed-off-by: default avatarThomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
parent fa576c58

arch/s390/kvm/intercept.c

+9 −16
Original line number Diff line number Diff line
@@ -292,33 +292,26 @@ static int handle_external_interrupt(struct kvm_vcpu *vcpu) 
 */

static int handle_mvpg_pei(struct kvm_vcpu *vcpu)

{

	unsigned long hostaddr, srcaddr, dstaddr;

	psw_t *psw = &vcpu->arch.sie_block->gpsw;

	struct mm_struct *mm = current->mm;

	unsigned long srcaddr, dstaddr;

	int reg1, reg2, rc;



	kvm_s390_get_regs_rre(vcpu, &reg1, &reg2);

	srcaddr = kvm_s390_real_to_abs(vcpu, vcpu->run->s.regs.gprs[reg2]);

	dstaddr = kvm_s390_real_to_abs(vcpu, vcpu->run->s.regs.gprs[reg1]);



	/* Make sure that the source is paged-in */

	hostaddr = gmap_fault(srcaddr, vcpu->arch.gmap);

	if (IS_ERR_VALUE(hostaddr))

	srcaddr = kvm_s390_real_to_abs(vcpu, vcpu->run->s.regs.gprs[reg2]);

	if (kvm_is_error_gpa(vcpu->kvm, srcaddr))

		return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);

	down_read(&mm->mmap_sem);

	rc = get_user_pages(current, mm, hostaddr, 1, 0, 0, NULL, NULL);

	up_read(&mm->mmap_sem);

	if (rc < 0)

	rc = kvm_arch_fault_in_page(vcpu, srcaddr, 0);

	if (rc != 0)

		return rc;



	/* Make sure that the destination is paged-in */

	hostaddr = gmap_fault(dstaddr, vcpu->arch.gmap);

	if (IS_ERR_VALUE(hostaddr))

	dstaddr = kvm_s390_real_to_abs(vcpu, vcpu->run->s.regs.gprs[reg1]);

	if (kvm_is_error_gpa(vcpu->kvm, dstaddr))

		return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);

	down_read(&mm->mmap_sem);

	rc = get_user_pages(current, mm, hostaddr, 1, 1, 0, NULL, NULL);

	up_read(&mm->mmap_sem);

	if (rc < 0)

	rc = kvm_arch_fault_in_page(vcpu, dstaddr, 1);

	if (rc != 0)

		return rc;



	psw->addr = __rewind_psw(*psw, 4);