On Mon, Aug 05, 2024, Oliver Upton wrote:

quoted

quoted

---
 arch/arm64/kvm/mmu.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 22ee37360c4e..ce13c3d884d5 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c

@@ -1685,15 +1685,17 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
 	}
 
 out_unlock:
+	if (writable && !ret)
+		kvm_set_pfn_dirty(pfn);

I'm guessing you meant kvm_release_pfn_dirty() here, because this leaks
a reference.

Doh, I did indeed.  Alternatively, this could be:

	if (writable && !ret)
		kvm_set_pfn_dirty(pfn);

	kvm_release_pfn_clean(pfn);

It won't matter in the end, because this just becomes:

	kvm_release_faultin_page(kvm, page, !!ret, writable);

So I guess the question is if you prefer to make the switch to an if-else in this
path, or more implicitly in the conversion to kvm_release_faultin_page().

I made the same goof for RISC-V, perhaps to prove that I too can copy+paste arm64's
MMU code ;-)