From 4879f241720cda3e6c18a1713bf9b2ed2de14ee4 Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Mon, 19 Nov 2012 23:01:34 +0000 Subject: KVM: PPC: Book3S HV: Fix bug causing loss of page dirty state This fixes a bug where adding a new guest HPT entry via the H_ENTER hcall would lose the "changed" bit in the reverse map information for the guest physical page being mapped. The result was that the KVM_GET_DIRTY_LOG could return a zero bit for the page even though the page had been modified by the guest. This fixes it by only modifying the index and present bits in the reverse map entry, thus preserving the reference and change bits. We were also unnecessarily setting the reference bit, and this fixes that too. Signed-off-by: Paul Mackerras Signed-off-by: Alexander Graf --- arch/powerpc/kvm/book3s_hv_rm_mmu.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch') diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c index 362dffe4db10..ff2da5ce475c 100644 --- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c +++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c @@ -59,10 +59,10 @@ void kvmppc_add_revmap_chain(struct kvm *kvm, struct revmap_entry *rev, head->back = pte_index; } else { rev->forw = rev->back = pte_index; - i = pte_index; + *rmap = (*rmap & ~KVMPPC_RMAP_INDEX) | + pte_index | KVMPPC_RMAP_PRESENT; } - smp_wmb(); - *rmap = i | KVMPPC_RMAP_REFERENCED | KVMPPC_RMAP_PRESENT; /* unlock */ + unlock_rmap(rmap); } EXPORT_SYMBOL_GPL(kvmppc_add_revmap_chain); -- cgit v1.2.3