Switching the MMU from radix<->radix mode is tricky particularly as the
MMU can remain enabled and requires a certain sequence of SPR updates.
Move these together into their own functions.
This also includes the radix TLB check / flush because it's tied in to
MMU switching due to tlbiel getting LPID from LPIDR.
Reviewed-by: Alexey Kardashevskiy <a...@ozlabs.ru>
Signed-off-by: Nicholas Piggin <npig...@gmail.com>
---
arch/powerpc/kvm/book3s_hv.c | 62 ++++++++++++++++++++++++------------
1 file changed, 41 insertions(+), 21 deletions(-)
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 68914b26017b..287cd3e1b918 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -3478,12 +3478,49 @@ static noinline void kvmppc_run_core(struct
kvmppc_vcore *vc)
trace_kvmppc_run_core(vc, 1);
}
+static void switch_mmu_to_guest_radix(struct kvm *kvm, struct kvm_vcpu *vcpu,
u64 lpcr)
+{
+ struct kvmppc_vcore *vc = vcpu->arch.vcore;
+ struct kvm_nested_guest *nested = vcpu->arch.nested;
+ u32 lpid;
+
+ lpid = nested ? nested->shadow_lpid : kvm->arch.lpid;
+
+ /*
+ * All the isync()s are overkill but trivially follow the ISA
+ * requirements. Some can likely be replaced with justification
+ * comment for why they are not needed.
+ */
+ isync();
+ mtspr(SPRN_LPID, lpid);
+ isync();
+ mtspr(SPRN_LPCR, lpcr);
+ isync();
+ mtspr(SPRN_PID, vcpu->arch.pid);
+ isync();
+
+ /* TLBIEL must have LPIDR set, so set guest LPID before flushing. */
+ kvmppc_check_need_tlb_flush(kvm, vc->pcpu, nested);
+}
+
+static void switch_mmu_to_host_radix(struct kvm *kvm, u32 pid)
+{
+ isync();
+ mtspr(SPRN_PID, pid);
+ isync();
+ mtspr(SPRN_LPID, kvm->arch.host_lpid);
+ isync();
+ mtspr(SPRN_LPCR, kvm->arch.host_lpcr);
+ isync();
+}
+
/*
* Load up hypervisor-mode registers on P9.
*/
static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu *vcpu, u64 time_limit,
unsigned long lpcr)
{
+ struct kvm *kvm = vcpu->kvm;
struct kvmppc_vcore *vc = vcpu->arch.vcore;
s64 hdec;
u64 tb, purr, spurr;
@@ -3535,7 +3572,6 @@ static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu
*vcpu, u64 time_limit,
}
mtspr(SPRN_CIABR, vcpu->arch.ciabr);
mtspr(SPRN_IC, vcpu->arch.ic);
- mtspr(SPRN_PID, vcpu->arch.pid);
mtspr(SPRN_PSSCR, vcpu->arch.psscr | PSSCR_EC |
(local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG));
@@ -3549,8 +3585,7 @@ static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu
*vcpu, u64 time_limit,
mtspr(SPRN_AMOR, ~0UL);
- mtspr(SPRN_LPCR, lpcr);
- isync();
+ switch_mmu_to_guest_radix(kvm, vcpu, lpcr);
/*
* P9 suppresses the HDEC exception when LPCR[HDICE] = 0,
@@ -3593,7 +3628,6 @@ static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu
*vcpu, u64 time_limit,
mtspr(SPRN_DAWR1, host_dawr1);
mtspr(SPRN_DAWRX1, host_dawrx1);
}
- mtspr(SPRN_PID, host_pidr);
/*
* Since this is radix, do a eieio; tlbsync; ptesync sequence in
@@ -3608,9 +3642,6 @@ static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu
*vcpu, u64 time_limit,
if (cpu_has_feature(CPU_FTR_ARCH_31))
asm volatile(PPC_CP_ABORT);
- mtspr(SPRN_LPID, vcpu->kvm->arch.host_lpid); /* restore host LPID */
- isync();
-
vc->dpdes = mfspr(SPRN_DPDES);
vc->vtb = mfspr(SPRN_VTB);
mtspr(SPRN_DPDES, 0);
@@ -3627,7 +3658,8 @@ static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu
*vcpu, u64 time_limit,
}
mtspr(SPRN_HDEC, 0x7fffffff);
- mtspr(SPRN_LPCR, vcpu->kvm->arch.host_lpcr);
+
+ switch_mmu_to_host_radix(kvm, host_pidr);
return trap;
}
@@ -4181,7 +4213,7 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu, u64
time_limit,
{
struct kvm_run *run = vcpu->run;
int trap, r, pcpu;
- int srcu_idx, lpid;
+ int srcu_idx;
struct kvmppc_vcore *vc;
struct kvm *kvm = vcpu->kvm;
struct kvm_nested_guest *nested = vcpu->arch.nested;
@@ -4255,13 +4287,6 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu, u64
time_limit,
vc->vcore_state = VCORE_RUNNING;
trace_kvmppc_run_core(vc, 0);
- if (cpu_has_feature(CPU_FTR_HVMODE)) {
- lpid = nested ? nested->shadow_lpid : kvm->arch.lpid;
- mtspr(SPRN_LPID, lpid);
- isync();
- kvmppc_check_need_tlb_flush(kvm, pcpu, nested);
- }
-
guest_enter_irqoff();
srcu_idx = srcu_read_lock(&kvm->srcu);
@@ -4280,11 +4305,6 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu, u64
time_limit,
srcu_read_unlock(&kvm->srcu, srcu_idx);
- if (cpu_has_feature(CPU_FTR_HVMODE)) {
- mtspr(SPRN_LPID, kvm->arch.host_lpid);
- isync();
- }
-
set_irq_happened(trap);
kvmppc_set_host_core(pcpu);
--
2.23.0
