KVM: arm64: Remove stage 2 read fault check

In the non-NV case, read permission is always granted when mapping
stage-2, so checking for it doesn't bring much. On the other hand,
shadow stage-2 for NV guests could potentially have non-readable
mappings when we align the permissions with those that L1 set for L2, we
shouldn't be checking for read faults in this case either.

So just remove this check.

Suggested-by: Oliver Upton <oliver.upton@linux.dev>
Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Wei-Lin Chang <r09922117@csie.ntu.edu.tw>
Link: https://lore.kernel.org/r/20250908064806.4093081-1-r09922117@csie.ntu.edu.tw
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

Author: rhythm16

arch/arm64/kvm/mmu.c

@@ -1545,11 +1545,6 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
 	exec_fault = kvm_vcpu_trap_is_exec_fault(vcpu);
 	VM_BUG_ON(write_fault && exec_fault);
 
-	if (fault_is_perm && !write_fault && !exec_fault) {
-		kvm_err("Unexpected L2 read permission error\n");
-		return -EFAULT;
-	}
-
 	if (!is_protected_kvm_enabled())
 		memcache = &vcpu->arch.mmu_page_cache;
 	else