[PATCH 3.12 53/63] arm/arm64: kvm: drop inappropriate use of kvm_is_mmio_pfn()

From: Jiri Slaby
Date: Thu Apr 30 2015 - 08:18:33 EST


From: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

commit 07a9748c78cfc39b54f06125a216b67b9c8f09ed upstream.

Instead of using kvm_is_mmio_pfn() to decide whether a host region
should be stage 2 mapped with device attributes, add a new static
function kvm_is_device_pfn() that disregards RAM pages with the
reserved bit set, as those should usually not be mapped as device
memory.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Signed-off-by: Shannon Zhao <shannon.zhao@xxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
arch/arm/kvm/mmu.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 90422a536083..5c31e3fff597 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -644,6 +644,11 @@ static bool kvm_is_write_fault(struct kvm_vcpu *vcpu)
return kvm_vcpu_dabt_iswrite(vcpu);
}

+static bool kvm_is_device_pfn(unsigned long pfn)
+{
+ return !pfn_valid(pfn);
+}
+
static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
gfn_t gfn, struct kvm_memory_slot *memslot,
unsigned long fault_status)
@@ -684,7 +689,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
if (is_error_pfn(pfn))
return -EFAULT;

- if (kvm_is_mmio_pfn(pfn))
+ if (kvm_is_device_pfn(pfn))
mem_type = PAGE_S2_DEVICE;

new_pte = pfn_pte(pfn, mem_type);
--
2.3.5

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