Implement KVM_CAP_MEMORY_FAULT_INFO for efaults generated by
direct_map().
Since direct_map() traverses multiple levels of the shadow page table, it
seems like there are actually two correct guest physical address ranges
which could be provided.
1. A smaller range, more specific range, which potentially only
corresponds to a part of what could not be mapped.
start = gfn_round_for_level(fault->gfn, fault->goal_level)
length = KVM_PAGES_PER_HPAGE(fault->goal_level)
2. The entire range which could not be mapped
start = gfn_round_for_level(fault->gfn, fault->goal_level)
length = KVM_PAGES_PER_HPAGE(fault->goal_level)
Take the first approach, although it's possible the second is actually
preferable.
Signed-off-by: Anish Moorthy <amoorthy@xxxxxxxxxx>
---
arch/x86/kvm/mmu/mmu.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 937329bee654e..a965c048edde8 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3192,8 +3192,13 @@ static int direct_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
fault->req_level >= it.level);
}
- if (WARN_ON_ONCE(it.level != fault->goal_level))
+ if (WARN_ON_ONCE(it.level != fault->goal_level)) {
+ gfn_t rounded_gfn = gfn_round_for_level(fault->gfn, fault->goal_level);
+ uint64_t len = KVM_PAGES_PER_HPAGE(fault->goal_level);
+
+ kvm_populate_efault_info(vcpu, rounded_gfn, len);
return -EFAULT;
+ }
ret = mmu_set_spte(vcpu, fault->slot, it.sptep, ACC_ALL,
base_gfn, fault->pfn, fault);
--
2.40.0.577.gac1e443424-goog
