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authorRadim Krčmář <rkrcmar@redhat.com>2016-09-29 17:26:52 +0300
committerRadim Krčmář <rkrcmar@redhat.com>2016-09-29 17:26:52 +0300
commitd9ab710b85310e4ba9295f2b494eda54cf1a355a (patch)
tree439f5b76e1e85e792d6913056c7edf6923ba1b76 /arch/mips
parent40a6d2208481b1d57c80b33110dbf78f271be5a6 (diff)
parentbf18db4e7bd99f3a65bcc43225790b16af733321 (diff)
downloadlinux-d9ab710b85310e4ba9295f2b494eda54cf1a355a.tar.xz
Merge tag 'kvm_mips_4.9_1' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/kvm-mips into next
MIPS KVM updates for v4.9 - A couple of fixes in preparation for supporting MIPS EVA host kernels. - MIPS SMP host & TLB invalidation fixes.
Diffstat (limited to 'arch/mips')
-rw-r--r--arch/mips/include/asm/kvm_host.h17
-rw-r--r--arch/mips/kvm/emulate.c78
-rw-r--r--arch/mips/kvm/mips.c30
-rw-r--r--arch/mips/kvm/mmu.c16
-rw-r--r--arch/mips/kvm/trap_emul.c18
5 files changed, 143 insertions, 16 deletions
diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h
index 5f488dc8a7d5..07f58cfc1ab9 100644
--- a/arch/mips/include/asm/kvm_host.h
+++ b/arch/mips/include/asm/kvm_host.h
@@ -107,6 +107,20 @@
#define KVM_INVALID_INST 0xdeadbeef
#define KVM_INVALID_ADDR 0xdeadbeef
+/*
+ * EVA has overlapping user & kernel address spaces, so user VAs may be >
+ * PAGE_OFFSET. For this reason we can't use the default KVM_HVA_ERR_BAD of
+ * PAGE_OFFSET.
+ */
+
+#define KVM_HVA_ERR_BAD (-1UL)
+#define KVM_HVA_ERR_RO_BAD (-2UL)
+
+static inline bool kvm_is_error_hva(unsigned long addr)
+{
+ return IS_ERR_VALUE(addr);
+}
+
extern atomic_t kvm_mips_instance;
struct kvm_vm_stat {
@@ -314,6 +328,9 @@ struct kvm_vcpu_arch {
u32 guest_kernel_asid[NR_CPUS];
struct mm_struct guest_kernel_mm, guest_user_mm;
+ /* Guest ASID of last user mode execution */
+ unsigned int last_user_gasid;
+
int last_sched_cpu;
/* WAIT executed */
diff --git a/arch/mips/kvm/emulate.c b/arch/mips/kvm/emulate.c
index e788515f766b..4db4c0370859 100644
--- a/arch/mips/kvm/emulate.c
+++ b/arch/mips/kvm/emulate.c
@@ -846,6 +846,47 @@ enum emulation_result kvm_mips_emul_tlbr(struct kvm_vcpu *vcpu)
return EMULATE_FAIL;
}
+/**
+ * kvm_mips_invalidate_guest_tlb() - Indicates a change in guest MMU map.
+ * @vcpu: VCPU with changed mappings.
+ * @tlb: TLB entry being removed.
+ *
+ * This is called to indicate a single change in guest MMU mappings, so that we
+ * can arrange TLB flushes on this and other CPUs.
+ */
+static void kvm_mips_invalidate_guest_tlb(struct kvm_vcpu *vcpu,
+ struct kvm_mips_tlb *tlb)
+{
+ int cpu, i;
+ bool user;
+
+ /* No need to flush for entries which are already invalid */
+ if (!((tlb->tlb_lo[0] | tlb->tlb_lo[1]) & ENTRYLO_V))
+ return;
+ /* User address space doesn't need flushing for KSeg2/3 changes */
+ user = tlb->tlb_hi < KVM_GUEST_KSEG0;
+
+ preempt_disable();
+
+ /*
+ * Probe the shadow host TLB for the entry being overwritten, if one
+ * matches, invalidate it
+ */
+ kvm_mips_host_tlb_inv(vcpu, tlb->tlb_hi);
+
+ /* Invalidate the whole ASID on other CPUs */
+ cpu = smp_processor_id();
+ for_each_possible_cpu(i) {
+ if (i == cpu)
+ continue;
+ if (user)
+ vcpu->arch.guest_user_asid[i] = 0;
+ vcpu->arch.guest_kernel_asid[i] = 0;
+ }
+
+ preempt_enable();
+}
+
/* Write Guest TLB Entry @ Index */
enum emulation_result kvm_mips_emul_tlbwi(struct kvm_vcpu *vcpu)
{
@@ -865,11 +906,8 @@ enum emulation_result kvm_mips_emul_tlbwi(struct kvm_vcpu *vcpu)
}
tlb = &vcpu->arch.guest_tlb[index];
- /*
- * Probe the shadow host TLB for the entry being overwritten, if one
- * matches, invalidate it
- */
- kvm_mips_host_tlb_inv(vcpu, tlb->tlb_hi);
+
+ kvm_mips_invalidate_guest_tlb(vcpu, tlb);
tlb->tlb_mask = kvm_read_c0_guest_pagemask(cop0);
tlb->tlb_hi = kvm_read_c0_guest_entryhi(cop0);
@@ -898,11 +936,7 @@ enum emulation_result kvm_mips_emul_tlbwr(struct kvm_vcpu *vcpu)
tlb = &vcpu->arch.guest_tlb[index];
- /*
- * Probe the shadow host TLB for the entry being overwritten, if one
- * matches, invalidate it
- */
- kvm_mips_host_tlb_inv(vcpu, tlb->tlb_hi);
+ kvm_mips_invalidate_guest_tlb(vcpu, tlb);
tlb->tlb_mask = kvm_read_c0_guest_pagemask(cop0);
tlb->tlb_hi = kvm_read_c0_guest_entryhi(cop0);
@@ -1026,6 +1060,7 @@ enum emulation_result kvm_mips_emulate_CP0(union mips_instruction inst,
enum emulation_result er = EMULATE_DONE;
u32 rt, rd, sel;
unsigned long curr_pc;
+ int cpu, i;
/*
* Update PC and hold onto current PC in case there is
@@ -1127,16 +1162,31 @@ enum emulation_result kvm_mips_emulate_CP0(union mips_instruction inst,
} else if (rd == MIPS_CP0_TLB_HI && sel == 0) {
u32 nasid =
vcpu->arch.gprs[rt] & KVM_ENTRYHI_ASID;
- if ((KSEGX(vcpu->arch.gprs[rt]) != CKSEG0) &&
- ((kvm_read_c0_guest_entryhi(cop0) &
+ if (((kvm_read_c0_guest_entryhi(cop0) &
KVM_ENTRYHI_ASID) != nasid)) {
trace_kvm_asid_change(vcpu,
kvm_read_c0_guest_entryhi(cop0)
& KVM_ENTRYHI_ASID,
nasid);
- /* Blow away the shadow host TLBs */
- kvm_mips_flush_host_tlb(1);
+ /*
+ * Regenerate/invalidate kernel MMU
+ * context.
+ * The user MMU context will be
+ * regenerated lazily on re-entry to
+ * guest user if the guest ASID actually
+ * changes.
+ */
+ preempt_disable();
+ cpu = smp_processor_id();
+ kvm_get_new_mmu_context(&vcpu->arch.guest_kernel_mm,
+ cpu, vcpu);
+ vcpu->arch.guest_kernel_asid[cpu] =
+ vcpu->arch.guest_kernel_mm.context.asid[cpu];
+ for_each_possible_cpu(i)
+ if (i != cpu)
+ vcpu->arch.guest_kernel_asid[i] = 0;
+ preempt_enable();
}
kvm_write_c0_guest_entryhi(cop0,
vcpu->arch.gprs[rt]);
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index 49b25e74d0c7..ce961495b5e1 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -421,6 +421,31 @@ int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
return -ENOIOCTLCMD;
}
+/* Must be called with preemption disabled, just before entering guest */
+static void kvm_mips_check_asids(struct kvm_vcpu *vcpu)
+{
+ struct mips_coproc *cop0 = vcpu->arch.cop0;
+ int cpu = smp_processor_id();
+ unsigned int gasid;
+
+ /*
+ * Lazy host ASID regeneration for guest user mode.
+ * If the guest ASID has changed since the last guest usermode
+ * execution, regenerate the host ASID so as to invalidate stale TLB
+ * entries.
+ */
+ if (!KVM_GUEST_KERNEL_MODE(vcpu)) {
+ gasid = kvm_read_c0_guest_entryhi(cop0) & KVM_ENTRYHI_ASID;
+ if (gasid != vcpu->arch.last_user_gasid) {
+ kvm_get_new_mmu_context(&vcpu->arch.guest_user_mm, cpu,
+ vcpu);
+ vcpu->arch.guest_user_asid[cpu] =
+ vcpu->arch.guest_user_mm.context.asid[cpu];
+ vcpu->arch.last_user_gasid = gasid;
+ }
+ }
+}
+
int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
int r = 0;
@@ -448,6 +473,9 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
htw_stop();
trace_kvm_enter(vcpu);
+
+ kvm_mips_check_asids(vcpu);
+
r = vcpu->arch.vcpu_run(run, vcpu);
trace_kvm_out(vcpu);
@@ -1561,6 +1589,8 @@ skip_emul:
if (ret == RESUME_GUEST) {
trace_kvm_reenter(vcpu);
+ kvm_mips_check_asids(vcpu);
+
/*
* If FPU / MSA are enabled (i.e. the guest's FPU / MSA context
* is live), restore FCR31 / MSACSR.
diff --git a/arch/mips/kvm/mmu.c b/arch/mips/kvm/mmu.c
index 121008c0fcc9..03883ba806e2 100644
--- a/arch/mips/kvm/mmu.c
+++ b/arch/mips/kvm/mmu.c
@@ -250,15 +250,27 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
kvm_get_new_mmu_context(&vcpu->arch.guest_kernel_mm, cpu, vcpu);
vcpu->arch.guest_kernel_asid[cpu] =
vcpu->arch.guest_kernel_mm.context.asid[cpu];
+ newasid++;
+
+ kvm_debug("[%d]: cpu_context: %#lx\n", cpu,
+ cpu_context(cpu, current->mm));
+ kvm_debug("[%d]: Allocated new ASID for Guest Kernel: %#x\n",
+ cpu, vcpu->arch.guest_kernel_asid[cpu]);
+ }
+
+ if ((vcpu->arch.guest_user_asid[cpu] ^ asid_cache(cpu)) &
+ asid_version_mask(cpu)) {
+ u32 gasid = kvm_read_c0_guest_entryhi(vcpu->arch.cop0) &
+ KVM_ENTRYHI_ASID;
+
kvm_get_new_mmu_context(&vcpu->arch.guest_user_mm, cpu, vcpu);
vcpu->arch.guest_user_asid[cpu] =
vcpu->arch.guest_user_mm.context.asid[cpu];
+ vcpu->arch.last_user_gasid = gasid;
newasid++;
kvm_debug("[%d]: cpu_context: %#lx\n", cpu,
cpu_context(cpu, current->mm));
- kvm_debug("[%d]: Allocated new ASID for Guest Kernel: %#x\n",
- cpu, vcpu->arch.guest_kernel_asid[cpu]);
kvm_debug("[%d]: Allocated new ASID for Guest User: %#x\n", cpu,
vcpu->arch.guest_user_asid[cpu]);
}
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);