[v13,38/85] KVM: x86/mmu: Put direct prefetched pages via kvm_release_page_clean()

Commit Message

Sean Christopherson Oct. 10, 2024, 6:23 p.m. UTC

Use kvm_release_page_clean() to put prefeteched pages instead of calling
put_page() directly.  This will allow de-duplicating the prefetch code
between indirect and direct MMUs.

Note, there's a small functional change as kvm_release_page_clean() marks
the page/folio as accessed.  While it's not strictly guaranteed that the
guest will access the page, KVM won't intercept guest accesses, i.e. won't
mark the page accessed if it _is_ accessed by the guest (unless A/D bits
are disabled, but running without A/D bits is effectively limited to
pre-HSW Intel CPUs).

Tested-by: Alex Bennée <[e-mail]>
Signed-off-by: Sean Christopherson <[e-mail]>
---
 arch/x86/kvm/mmu/mmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Patch

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index e451e1b9a55a..62924f95a398 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -2965,7 +2965,7 @@  static int direct_pte_prefetch_many(struct kvm_vcpu *vcpu,
 	for (i = 0; i < ret; i++, gfn++, start++) {
 		mmu_set_spte(vcpu, slot, start, access, gfn,
 			     page_to_pfn(pages[i]), NULL);
-		put_page(pages[i]);
+		kvm_release_page_clean(pages[i]);
 	}
 
 	return 0;