Re: [PATCH v9 23/24] KVM: s390: arm64: Implement basic page fault handler

["Arnd Bergmann" <arnd@arndb.de>]

> +		/*
> +		 * Check for a cache maintenance operation. Assume the guest is
> +		 * cautious and skip instruction
> +		 */
> +		if (kvm_is_error_hva(hva) && kvm_vcpu_dabt_is_cm(vcpu)) {
> +			kvm_incr_pc(vcpu);
> +			ret = 1;
> +			goto out_unlock;

Hi Steffen,

[Adding Lorenzo Stoakes to Cc]

I see this function fails to build on top of linux-next, as the 
kvm_vcpu_dabt_is_cm() function was removed by commit 18b94675b1fb
("KVM: arm64: Use ESR helpers in guest abort handling").

I used this patch to make it build, but I'm not sure if this is
the correct fix:

diff --git a/arch/s390/kvm/arm64/mmu.c b/arch/s390/kvm/arm64/mmu.c
index 3c1c8a2def73..7ee157c61d70 100644
--- a/arch/s390/kvm/arm64/mmu.c
+++ b/arch/s390/kvm/arm64/mmu.c
@@ -119,6 +119,7 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu)
 	hva = gfn_to_hva_memslot_prot(memslot, gfn, &writable);
 	write_fault = kvm_s390_cur_gmap_fault_is_write(vcpu);
 	if (kvm_is_error_hva(hva) || (write_fault && !writable)) {
+		unsigned long esr = kvm_vcpu_get_esr(vcpu);
 		ret = -ENOEXEC;
 		/*
 		 * The guest has put either its instructions or its page-tables
@@ -143,7 +144,7 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu)
 		 * Check for a cache maintenance operation. Assume the guest is
 		 * cautious and skip instruction
 		 */
-		if (kvm_is_error_hva(hva) && kvm_vcpu_dabt_is_cm(vcpu)) {
+		if (kvm_is_error_hva(hva) && esr_dabt_is_cm(esr)) {
 			kvm_incr_pc(vcpu);
 			ret = 1;
 			goto out_unlock;


      Arnd