s390/kvm,tprot: use new gmap_translate() function (59a1fa2d) · Commits · 戴 / test

When out-of-memory the tprot code incorrectly injected a program check for the guest which reported an addressing exception even if the guest address was valid. Let's use the new gmap_translate() which translates a guest address to a user space address whithout the chance of running into an out-of-memory situation. Also make it more explicit that for -EFAULT we won't find a vma. Signed-off-by:

Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by:

Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by:

Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by:

Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by:

Marcelo Tosatti <mtosatti@redhat.com>

arch/s390/kvm/priv.c

+9 −12

Original line number	Diff line number	Diff line
		@@ -575,20 +575,13 @@ static int handle_tprot(struct kvm_vcpu *vcpu)
		if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_DAT)
		return -EOPNOTSUPP;


		/* we must resolve the address without holding the mmap semaphore.
		* This is ok since the userspace hypervisor is not supposed to change
		* the mapping while the guest queries the memory. Otherwise the guest
		* might crash or get wrong info anyway. */
		user_address = (unsigned long) __guestaddr_to_user(vcpu, address1);

		down_read(&current->mm->mmap_sem);
		user_address = __gmap_translate(address1, vcpu->arch.gmap);
		if (IS_ERR_VALUE(user_address))
		goto out_inject;
		vma = find_vma(current->mm, user_address);
		if (!vma) {
		up_read(&current->mm->mmap_sem);
		return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
		}

		if (!vma)
		goto out_inject;
		vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
		if (!(vma->vm_flags & VM_WRITE) && (vma->vm_flags & VM_READ))
		vcpu->arch.sie_block->gpsw.mask \|= (1ul << 44);
		@@ -597,6 +590,10 @@ static int handle_tprot(struct kvm_vcpu *vcpu)

		up_read(&current->mm->mmap_sem);
		return 0;

		out_inject:
		up_read(&current->mm->mmap_sem);
		return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
		}

		int kvm_s390_handle_e5(struct kvm_vcpu *vcpu)

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