On Wed, Nov 10, 2021 at 02:29:52PM -0800, Ben Gardon wrote:

When recursively clearing out disconnected pts, the range based TLB flush in handle_removed_tdp_mmu_page uses the wrong starting GFN, resulting in the flush mostly missing the affected range. Fix this by using base_gfn for the flush.

Fixes: a066e61f13cf ("KVM: x86/mmu: Factor out handling of removed page tables") CC: stable@vger.kernel.org

Signed-off-by: Ben Gardon bgardon@google.com

arch/x86/kvm/mmu/tdp_mmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index 7c5dd83e52de..866c2b191e1e 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -374,7 +374,7 @@ static void handle_removed_tdp_mmu_page(struct kvm *kvm, tdp_ptep_t pt, shared); }

• kvm_flush_remote_tlbs_with_address(kvm, gfn,

• kvm_flush_remote_tlbs_with_address(kvm, base_gfn,

Suggest pulling the definition of gfn into the for loop as well (along with sptep and old_child_spte for that matter) so that referencing it here isn't even possible.

			   KVM_PAGES_PER_HPAGE(level + 1));

call_rcu(&sp->rcu_head, tdp_mmu_free_sp_rcu_callback); -- 2.34.0.rc0.344.g81b53c2807-goog