KVM: PPC: Book3S HV: Save/restore SIAR and SDAR along with other PMU registers

Currently we are not saving and restoring the SIAR and SDAR registers in
the PMU (performance monitor unit) on guest entry and exit.  The result
is that performance monitoring tools in the guest could get false
information about where a program was executing and what data it was
accessing at the time of a performance monitor interrupt.  This fixes
it by saving and restoring these registers along with the other PMU
registers on guest entry/exit.

This also provides a way for userspace to access these values for a
vcpu via the one_reg interface.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>

diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 0866230b7c2dcda8f30660f42759876bd9e980a6..d9b21af62610681dd48cda19c583fba23809706c 100644 (file)
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -493,6 +493,8 @@ struct kvm_vcpu_arch {
 
        u64 mmcr[3];
        u32 pmc[8];
+       u64 siar;
+       u64 sdar;
 
 #ifdef CONFIG_KVM_EXIT_TIMING
        struct mutex exit_timing_lock;

diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index d8958be5f31a18b7c0bae16509749067aae75265..19e699d747b79345b7fb81cd721530a8ee5038eb 100644 (file)
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -508,6 +508,8 @@ int main(void)
        DEFINE(VCPU_PRODDED, offsetof(struct kvm_vcpu, arch.prodded));
        DEFINE(VCPU_MMCR, offsetof(struct kvm_vcpu, arch.mmcr));
        DEFINE(VCPU_PMC, offsetof(struct kvm_vcpu, arch.pmc));
+       DEFINE(VCPU_SIAR, offsetof(struct kvm_vcpu, arch.siar));
+       DEFINE(VCPU_SDAR, offsetof(struct kvm_vcpu, arch.sdar));
        DEFINE(VCPU_SLB, offsetof(struct kvm_vcpu, arch.slb));
        DEFINE(VCPU_SLB_MAX, offsetof(struct kvm_vcpu, arch.slb_max));
        DEFINE(VCPU_SLB_NR, offsetof(struct kvm_vcpu, arch.slb_nr));

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 62a2b5ab08eda0399bf009b81eebd36d587763d8..45a9b876b0a046f3e4adb6981ce89ed2abbb61af 100644 (file)
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -749,6 +749,12 @@ int kvmppc_get_one_reg(struct kvm_vcpu *vcpu, u64 id, union kvmppc_one_reg *val)
                i = id - KVM_REG_PPC_PMC1;
                *val = get_reg_val(id, vcpu->arch.pmc[i]);
                break;
+       case KVM_REG_PPC_SIAR:
+               *val = get_reg_val(id, vcpu->arch.siar);
+               break;
+       case KVM_REG_PPC_SDAR:
+               *val = get_reg_val(id, vcpu->arch.sdar);
+               break;
 #ifdef CONFIG_VSX
        case KVM_REG_PPC_FPR0 ... KVM_REG_PPC_FPR31:
                if (cpu_has_feature(CPU_FTR_VSX)) {
@@ -833,6 +839,12 @@ int kvmppc_set_one_reg(struct kvm_vcpu *vcpu, u64 id, union kvmppc_one_reg *val)
                i = id - KVM_REG_PPC_PMC1;
                vcpu->arch.pmc[i] = set_reg_val(id, *val);
                break;
+       case KVM_REG_PPC_SIAR:
+               vcpu->arch.siar = set_reg_val(id, *val);
+               break;
+       case KVM_REG_PPC_SDAR:
+               vcpu->arch.sdar = set_reg_val(id, *val);
+               break;
 #ifdef CONFIG_VSX
        case KVM_REG_PPC_FPR0 ... KVM_REG_PPC_FPR31:
                if (cpu_has_feature(CPU_FTR_VSX)) {

diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 294b7af28cdd3c58b2551c53b9210daa429f836d..541aea0ce91a05724ec92a28b96387e64268a9fb 100644 (file)
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -200,8 +200,12 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_201)
        ld      r3, VCPU_MMCR(r4)
        ld      r5, VCPU_MMCR + 8(r4)
        ld      r6, VCPU_MMCR + 16(r4)
+       ld      r7, VCPU_SIAR(r4)
+       ld      r8, VCPU_SDAR(r4)
        mtspr   SPRN_MMCR1, r5
        mtspr   SPRN_MMCRA, r6
+       mtspr   SPRN_SIAR, r7
+       mtspr   SPRN_SDAR, r8
        mtspr   SPRN_MMCR0, r3
        isync
 
@@ -1134,9 +1138,13 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
        std     r3, VCPU_MMCR(r9)       /* if not, set saved MMCR0 to FC */
        b       22f
 21:    mfspr   r5, SPRN_MMCR1
+       mfspr   r7, SPRN_SIAR
+       mfspr   r8, SPRN_SDAR
        std     r4, VCPU_MMCR(r9)
        std     r5, VCPU_MMCR + 8(r9)
        std     r6, VCPU_MMCR + 16(r9)
+       std     r7, VCPU_SIAR(r9)
+       std     r8, VCPU_SDAR(r9)
        mfspr   r3, SPRN_PMC1
        mfspr   r4, SPRN_PMC2
        mfspr   r5, SPRN_PMC3