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| author | James Hogan <james.hogan@imgtec.com> | 2016-07-08 13:53:22 +0300 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2016-08-01 19:42:22 +0300 |
| commit | 28cc5bd568745a58bb06291ac336d06b66c66dff (patch) | |
| tree | d8c1dd5dd137177910f127f125e0e402be3ffded /arch/mips/kvm/mmu.c | |
| parent | cfacaced0cce20859de25b61d672edeb9789a1e9 (diff) | |
| download | linux-28cc5bd568745a58bb06291ac336d06b66c66dff.tar.xz | |
MIPS: KVM: Use kmap instead of CKSEG0ADDR()
There are several unportable uses of CKSEG0ADDR() in MIPS KVM, which
implicitly assume that a host physical address will be in the low 512MB
of the physical address space (accessible in KSeg0). These assumptions
don't hold for highmem or on 64-bit kernels.
When interpreting the guest physical address when reading or overwriting
a trapping instruction, use kmap_atomic() to get a usable virtual
address to access guest memory, which is portable to 64-bit and highmem
kernels.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/mips/kvm/mmu.c')
| -rw-r--r-- | arch/mips/kvm/mmu.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/arch/mips/kvm/mmu.c b/arch/mips/kvm/mmu.c index ecead748de04..57319ee57c4f 100644 --- a/arch/mips/kvm/mmu.c +++ b/arch/mips/kvm/mmu.c @@ -9,6 +9,7 @@ * Authors: Sanjay Lal <sanjayl@kymasys.com> */ +#include <linux/highmem.h> #include <linux/kvm_host.h> #include <asm/mmu_context.h> @@ -330,6 +331,7 @@ u32 kvm_get_inst(u32 *opc, struct kvm_vcpu *vcpu) struct mips_coproc *cop0 = vcpu->arch.cop0; unsigned long paddr, flags, vpn2, asid; unsigned long va = (unsigned long)opc; + void *vaddr; u32 inst; int index; @@ -360,7 +362,10 @@ u32 kvm_get_inst(u32 *opc, struct kvm_vcpu *vcpu) local_irq_restore(flags); } else if (KVM_GUEST_KSEGX(va) == KVM_GUEST_KSEG0) { paddr = kvm_mips_translate_guest_kseg0_to_hpa(vcpu, va); - inst = *(u32 *) CKSEG0ADDR(paddr); + vaddr = kmap_atomic(pfn_to_page(PHYS_PFN(paddr))); + vaddr += paddr & ~PAGE_MASK; + inst = *(u32 *)vaddr; + kunmap_atomic(vaddr); } else { kvm_err("%s: illegal address: %p\n", __func__, opc); return KVM_INVALID_INST; |