Subject: [PATCH 06/17] KVM: arm64: Kill write_fault from kvm_s2_fault

From: Marc Zyngier <[email-masked]>
Date: Mon, 16 Mar 2026 17:54:39 +0000

We already have kvm_is_write_fault() as a predicate indicating
a S2 fault on a write, and we're better off just using that instead
of duplicating the state.

Signed-off-by: Marc Zyngier <[email-masked]>
---
 arch/arm64/kvm/mmu.c | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 12c2f0aeaae4c..86950acbd7e6b 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -1711,7 +1711,6 @@ static short kvm_s2_resolve_vma_size(const struct kvm_s2_fault_desc *s2fd,
 }
 
 struct kvm_s2_fault {
-	bool write_fault;
 	bool exec_fault;
 	bool writable;
 	bool topup_memcache;
@@ -1799,7 +1798,7 @@ static int kvm_s2_fault_pin_pfn(const struct kvm_s2_fault_desc *s2fd,
 		return ret;
 
 	fault->pfn = __kvm_faultin_pfn(s2fd->memslot, get_canonical_gfn(s2fd, fault),
-				       fault->write_fault ? FOLL_WRITE : 0,
+				       kvm_is_write_fault(s2fd->vcpu) ? FOLL_WRITE : 0,
 				       &fault->writable, &fault->page);
 	if (unlikely(is_error_noslot_pfn(fault->pfn))) {
 		if (fault->pfn == KVM_PFN_ERR_HWPOISON) {
@@ -1850,7 +1849,7 @@ static int kvm_s2_fault_compute_prot(const struct kvm_s2_fault_desc *s2fd,
 			 */
 			fault->s2_force_noncacheable = true;
 		}
-	} else if (fault->logging_active && !fault->write_fault) {
+	} else if (fault->logging_active && !kvm_is_write_fault(s2fd->vcpu)) {
 		/*
 		 * Only actually map the page as writable if this was a write
 		 * fault.
@@ -1980,21 +1979,17 @@ static int kvm_s2_fault_map(const struct kvm_s2_fault_desc *s2fd,
 static int user_mem_abort(const struct kvm_s2_fault_desc *s2fd)
 {
 	bool perm_fault = kvm_vcpu_trap_is_permission_fault(s2fd->vcpu);
-	bool write_fault = kvm_is_write_fault(s2fd->vcpu);
 	bool logging_active = memslot_is_logging(s2fd->memslot);
 	struct kvm_s2_fault fault = {
 		.logging_active = logging_active,
 		.force_pte = logging_active,
 		.prot = KVM_PGTABLE_PROT_R,
-		.write_fault = write_fault,
 		.exec_fault = kvm_vcpu_trap_is_exec_fault(s2fd->vcpu),
-		.topup_memcache = !perm_fault || (logging_active && write_fault),
+		.topup_memcache = !perm_fault || (logging_active && kvm_is_write_fault(s2fd->vcpu)),
 	};
 	void *memcache;
 	int ret;
 
-	VM_WARN_ON_ONCE(fault.write_fault && fault.exec_fault);
-
 	/*
 	 * Permission faults just need to update the existing leaf entry,
 	 * and so normally don't require allocations from the memcache. The
-- 
2.47.3