From ae41d7dbaeb4f79134136cd65ad7015cf9ccf78a Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Fri, 26 Jul 2024 16:51:10 -0700 Subject: [PATCH] KVM: arm64: Release pfn, i.e. put page, if copying MTE tags hits ZONE_DEVICE Put the page reference acquired by gfn_to_pfn_prot() if kvm_vm_ioctl_mte_copy_tags() runs into ZONE_DEVICE memory. KVM's less- than-stellar heuristics for dealing with pfn-mapped memory means that KVM can get a page reference to ZONE_DEVICE memory. Fixes: f0376edb1ddc ("KVM: arm64: Add ioctl to fetch/store tags in a guest") Signed-off-by: Sean Christopherson Reviewed-by: Steven Price Reviewed-by: Catalin Marinas Link: https://lore.kernel.org/r/20240726235234.228822-2-seanjc@google.com Signed-off-by: Marc Zyngier --- arch/arm64/kvm/guest.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index 11098eb7eb44a..e1f0ff08836a3 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -1059,6 +1059,7 @@ int kvm_vm_ioctl_mte_copy_tags(struct kvm *kvm, page = pfn_to_online_page(pfn); if (!page) { /* Reject ZONE_DEVICE memory */ + kvm_release_pfn_clean(pfn); ret = -EFAULT; goto out; } -- 2.47.2