KVM: Fix missing smp tlb flush in invlpg
When kvm emulates an invlpg instruction, it can drop a shadow pte, but leaves the guest tlbs intact. This can cause memory corruption when swapping out. Without this the other cpu can still write to a freed host physical page. tlb smp flush must happen if rmap_remove is called always before mmu_lock is released because the VM will take the mmu_lock before it can finally add the page to the freelist after swapout. mmu notifier makes it safe to flush the tlb after freeing the page (otherwise it would never be safe) so we can do a single flush for multiple sptes invalidated. Cc: stable@kernel.org Signed-off-by:Andrea Arcangeli <aarcange@redhat.com> Acked-by:
Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by:
Avi Kivity <avi@redhat.com>
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