Commit b3cefd6b authored by Janis Schoetterl-Glausch's avatar Janis Schoetterl-Glausch Committed by Janosch Frank
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KVM: s390: Pass initialized arg even if unused 



This silences smatch warnings reported by kbuild bot:
arch/s390/kvm/gaccess.c:859 guest_range_to_gpas() error: uninitialized symbol 'prot'.
arch/s390/kvm/gaccess.c:1064 access_guest_with_key() error: uninitialized symbol 'prot'.

This is because it cannot tell that the value is not used in this case.
The trans_exc* only examine prot if code is PGM_PROTECTION.
Pass a dummy value for other codes.

Reported-by: default avatarkernel test robot <lkp@intel.com>
Reported-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: default avatarJanis Schoetterl-Glausch <scgl@linux.ibm.com>
Reviewed-by: default avatarClaudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20220825192540.1560559-1-scgl@linux.ibm.com


Signed-off-by: default avatarChristian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: default avatarJanosch Frank <frankja@linux.ibm.com>
parent e8c924a4

arch/s390/kvm/gaccess.c

+13 −3
Original line number Diff line number Diff line
@@ -489,6 +489,8 @@ enum prot_type { 
	PROT_TYPE_ALC  = 2,

	PROT_TYPE_DAT  = 3,

	PROT_TYPE_IEP  = 4,

	/* Dummy value for passing an initialized value when code != PGM_PROTECTION */

	PROT_NONE,

};



static int trans_exc_ending(struct kvm_vcpu *vcpu, int code, unsigned long gva, u8 ar,
@@ -504,6 +506,10 @@ static int trans_exc_ending(struct kvm_vcpu *vcpu, int code, unsigned long gva, 
	switch (code) {

	case PGM_PROTECTION:

		switch (prot) {

		case PROT_NONE:

			/* We should never get here, acts like termination */

			WARN_ON_ONCE(1);

			break;

		case PROT_TYPE_IEP:

			tec->b61 = 1;

			fallthrough;
@@ -968,8 +974,10 @@ static int guest_range_to_gpas(struct kvm_vcpu *vcpu, unsigned long ga, u8 ar, 
				return rc;

		} else {

			gpa = kvm_s390_real_to_abs(vcpu, ga);

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

			if (kvm_is_error_gpa(vcpu->kvm, gpa)) {

				rc = PGM_ADDRESSING;

				prot = PROT_NONE;

			}

		}

		if (rc)

			return trans_exc(vcpu, rc, ga, ar, mode, prot);
@@ -1112,8 +1120,6 @@ int access_guest_with_key(struct kvm_vcpu *vcpu, unsigned long ga, u8 ar, 
		if (rc == PGM_PROTECTION && try_storage_prot_override)

			rc = access_guest_page_with_key(vcpu->kvm, mode, gpas[idx],

							data, fragment_len, PAGE_SPO_ACC);

		if (rc == PGM_PROTECTION)

			prot = PROT_TYPE_KEYC;

		if (rc)

			break;

		len -= fragment_len;
@@ -1123,6 +1129,10 @@ int access_guest_with_key(struct kvm_vcpu *vcpu, unsigned long ga, u8 ar, 
	if (rc > 0) {

		bool terminate = (mode == GACC_STORE) && (idx > 0);



		if (rc == PGM_PROTECTION)

			prot = PROT_TYPE_KEYC;

		else

			prot = PROT_NONE;

		rc = trans_exc_ending(vcpu, rc, ga, ar, mode, prot, terminate);

	}

out_unlock: