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| author | James Hogan <james.hogan@imgtec.com> | 2016-08-19 16:09:47 +0200 |
|---|---|---|
| committer | James Hogan <james.hogan@imgtec.com> | 2016-09-08 19:29:54 +0200 |
| commit | d5888477d31c64dba9264fbb33cfa9b066f071d0 (patch) | |
| tree | fdc2e5eb025f4f977b78f78ef4e76e786781886d /arch | |
| parent | KVM: MIPS: Override HVA error values for EVA (diff) | |
| download | linux-d5888477d31c64dba9264fbb33cfa9b066f071d0.tar.xz linux-d5888477d31c64dba9264fbb33cfa9b066f071d0.zip | |
KVM: MIPS: Emulate MMIO via TLB miss for EVA
MIPS Enhanced Virtual Addressing (EVA) allows the virtual memory
segments to be rearranged such that the KSeg0/KSeg1 segments are
accessible TLB mapped to user mode, which would trigger a TLB Miss
exception (due to lack of TLB mappings) instead of an Address Error
exception.
Update the TLB Miss handling similar to Address Error handling for guest
MMIO emulation.
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
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/mips/kvm/trap_emul.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/arch/mips/kvm/trap_emul.c b/arch/mips/kvm/trap_emul.c index 091553942bcb..3a5484f9aa50 100644 --- a/arch/mips/kvm/trap_emul.c +++ b/arch/mips/kvm/trap_emul.c @@ -175,6 +175,24 @@ static int kvm_trap_emul_handle_tlb_miss(struct kvm_vcpu *vcpu, bool store) run->exit_reason = KVM_EXIT_INTERNAL_ERROR; ret = RESUME_HOST; } + } else if (KVM_GUEST_KERNEL_MODE(vcpu) + && (KSEGX(badvaddr) == CKSEG0 || KSEGX(badvaddr) == CKSEG1)) { + /* + * With EVA we may get a TLB exception instead of an address + * error when the guest performs MMIO to KSeg1 addresses. + */ + kvm_debug("Emulate %s MMIO space\n", + store ? "Store to" : "Load from"); + er = kvm_mips_emulate_inst(cause, opc, run, vcpu); + if (er == EMULATE_FAIL) { + kvm_err("Emulate %s MMIO space failed\n", + store ? "Store to" : "Load from"); + run->exit_reason = KVM_EXIT_INTERNAL_ERROR; + ret = RESUME_HOST; + } else { + run->exit_reason = KVM_EXIT_MMIO; + ret = RESUME_HOST; + } } else { kvm_err("Illegal TLB %s fault address , cause %#x, PC: %p, BadVaddr: %#lx\n", store ? "ST" : "LD", cause, opc, badvaddr); |