Commit 5f9df945 authored by Claudio Imbrenda's avatar Claudio Imbrenda Committed by Janosch Frank
Browse files

KVM: s390: Fix FOLL_*/FAULT_FLAG_* confusion 



Pass the right type of flag to vcpu_dat_fault_handler(); it expects a
FOLL_* flag (in particular FOLL_WRITE), but FAULT_FLAG_WRITE is passed
instead.

This still works because they happen to have the same integer value,
but it's a mistake, thus the fix.

Signed-off-by: default avatarClaudio Imbrenda <imbrenda@linux.ibm.com>
Fixes: 05066caf ("s390/mm/fault: Handle guest-related program interrupts in KVM")
Acked-by: default avatarChristian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: default avatarDavid Hildenbrand <david@redhat.com>
Reviewed-by: default avatarSteffen Eiden <seiden@linux.ibm.com>
Reviewed-by: default avatarChristoph Schlameuss <schlameuss@linux.ibm.com>
Signed-off-by: default avatarJanosch Frank <frankja@linux.ibm.com>
parent 185d9030

arch/s390/kvm/kvm-s390.c

+12 −12
Original line number Diff line number Diff line
@@ -4864,12 +4864,12 @@ static void kvm_s390_assert_primary_as(struct kvm_vcpu *vcpu) 
 * @vcpu: the vCPU whose gmap is to be fixed up

 * @gfn: the guest frame number used for memslots (including fake memslots)

 * @gaddr: the gmap address, does not have to match @gfn for ucontrol gmaps

 * @flags: FOLL_* flags

 * @foll: FOLL_* flags

 *

 * Return: 0 on success, < 0 in case of error.

 * Context: The mm lock must not be held before calling. May sleep.

 */

int __kvm_s390_handle_dat_fault(struct kvm_vcpu *vcpu, gfn_t gfn, gpa_t gaddr, unsigned int flags)

int __kvm_s390_handle_dat_fault(struct kvm_vcpu *vcpu, gfn_t gfn, gpa_t gaddr, unsigned int foll)

{

	struct kvm_memory_slot *slot;

	unsigned int fault_flags;
@@ -4883,13 +4883,13 @@ int __kvm_s390_handle_dat_fault(struct kvm_vcpu *vcpu, gfn_t gfn, gpa_t gaddr, u 
	if (!slot || slot->flags & KVM_MEMSLOT_INVALID)

		return vcpu_post_run_addressing_exception(vcpu);



	fault_flags = flags & FOLL_WRITE ? FAULT_FLAG_WRITE : 0;

	fault_flags = foll & FOLL_WRITE ? FAULT_FLAG_WRITE : 0;

	if (vcpu->arch.gmap->pfault_enabled)

		flags |= FOLL_NOWAIT;

		foll |= FOLL_NOWAIT;

	vmaddr = __gfn_to_hva_memslot(slot, gfn);



try_again:

	pfn = __kvm_faultin_pfn(slot, gfn, flags, &writable, &page);

	pfn = __kvm_faultin_pfn(slot, gfn, foll, &writable, &page);



	/* Access outside memory, inject addressing exception */

	if (is_noslot_pfn(pfn))
@@ -4905,7 +4905,7 @@ int __kvm_s390_handle_dat_fault(struct kvm_vcpu *vcpu, gfn_t gfn, gpa_t gaddr, u 
			return 0;

		vcpu->stat.pfault_sync++;

		/* Could not setup async pfault, try again synchronously */

		flags &= ~FOLL_NOWAIT;

		foll &= ~FOLL_NOWAIT;

		goto try_again;

	}

	/* Any other error */
@@ -4925,7 +4925,7 @@ int __kvm_s390_handle_dat_fault(struct kvm_vcpu *vcpu, gfn_t gfn, gpa_t gaddr, u 
	return rc;

}



static int vcpu_dat_fault_handler(struct kvm_vcpu *vcpu, unsigned long gaddr, unsigned int flags)

static int vcpu_dat_fault_handler(struct kvm_vcpu *vcpu, unsigned long gaddr, unsigned int foll)

{

	unsigned long gaddr_tmp;

	gfn_t gfn;
@@ -4950,18 +4950,18 @@ static int vcpu_dat_fault_handler(struct kvm_vcpu *vcpu, unsigned long gaddr, un 
		}

		gfn = gpa_to_gfn(gaddr_tmp);

	}

	return __kvm_s390_handle_dat_fault(vcpu, gfn, gaddr, flags);

	return __kvm_s390_handle_dat_fault(vcpu, gfn, gaddr, foll);

}



static int vcpu_post_run_handle_fault(struct kvm_vcpu *vcpu)

{

	unsigned int flags = 0;

	unsigned int foll = 0;

	unsigned long gaddr;

	int rc;



	gaddr = current->thread.gmap_teid.addr * PAGE_SIZE;

	if (kvm_s390_cur_gmap_fault_is_write())

		flags = FAULT_FLAG_WRITE;

		foll = FOLL_WRITE;



	switch (current->thread.gmap_int_code & PGM_INT_CODE_MASK) {

	case 0:
@@ -5003,7 +5003,7 @@ static int vcpu_post_run_handle_fault(struct kvm_vcpu *vcpu) 
			send_sig(SIGSEGV, current, 0);

		if (rc != -ENXIO)

			break;

		flags = FAULT_FLAG_WRITE;

		foll = FOLL_WRITE;

		fallthrough;

	case PGM_PROTECTION:

	case PGM_SEGMENT_TRANSLATION:
@@ -5013,7 +5013,7 @@ static int vcpu_post_run_handle_fault(struct kvm_vcpu *vcpu) 
	case PGM_REGION_SECOND_TRANS:

	case PGM_REGION_THIRD_TRANS:

		kvm_s390_assert_primary_as(vcpu);

		return vcpu_dat_fault_handler(vcpu, gaddr, flags);

		return vcpu_dat_fault_handler(vcpu, gaddr, foll);

	default:

		KVM_BUG(1, vcpu->kvm, "Unexpected program interrupt 0x%x, TEID 0x%016lx",

			current->thread.gmap_int_code, current->thread.gmap_teid.val);