[PATCH 0/3] KVM: MMU: fix kvm_is_mmio_pfn()

From: Haozhong Zhang
Date: Thu Oct 26 2017 - 22:25:53 EST


[I just copy the commit message from patch 3]

By default, KVM treats a reserved page as for MMIO purpose, and maps
it to guest with UC memory type. However, some reserved pages are not
for MMIO, such as pages of DAX device (e.g., /dev/daxX.Y). Mapping
them with UC memory type will harm the performance. In order to
exclude those cases, we check the host cache mode in addition and only
treat UC/UC- pages as MMIO.

Haozhong Zhang (3):
x86/mm: expose track_pfn_insert()
KVM: add converters between pfn_t and kvm_pfn_t
KVM: MMU: consider host cache type in MMIO pfn check

arch/x86/kvm/mmu.c | 32 +++++++++++++++++++++++++++++---
arch/x86/mm/pat.c | 1 +
include/linux/kvm_host.h | 3 +++
3 files changed, 33 insertions(+), 3 deletions(-)

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2.14.1