From 468a12c2b53776721ff83517d4a195b85c5fce54 Mon Sep 17 00:00:00 2001 From: Alexander Graf Date: Fri, 9 Dec 2011 14:44:13 +0100 Subject: KVM: PPC: Use get/set for to_svcpu to help preemption MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When running the 64-bit Book3s PR code without CONFIG_PREEMPT_NONE, we were doing a few things wrong, most notably access to PACA fields without making sure that the pointers stay stable accross the access (preempt_disable()). This patch moves to_svcpu towards a get/put model which allows us to disable preemption while accessing the shadow vcpu fields in the PACA. That way we can run preemptible and everyone's happy! Reported-by: Jörg Sommer Signed-off-by: Alexander Graf Signed-off-by: Avi Kivity --- arch/powerpc/include/asm/kvm_book3s.h | 76 +++++++++++++++++++++++++++-------- 1 file changed, 59 insertions(+), 17 deletions(-) (limited to 'arch/powerpc/include/asm/kvm_book3s.h') diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h index 69c7377d207..c941c21a189 100644 --- a/arch/powerpc/include/asm/kvm_book3s.h +++ b/arch/powerpc/include/asm/kvm_book3s.h @@ -183,7 +183,9 @@ static inline void kvmppc_update_int_pending(struct kvm_vcpu *vcpu, static inline void kvmppc_set_gpr(struct kvm_vcpu *vcpu, int num, ulong val) { if ( num < 14 ) { - to_svcpu(vcpu)->gpr[num] = val; + struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); + svcpu->gpr[num] = val; + svcpu_put(svcpu); to_book3s(vcpu)->shadow_vcpu->gpr[num] = val; } else vcpu->arch.gpr[num] = val; @@ -191,80 +193,120 @@ static inline void kvmppc_set_gpr(struct kvm_vcpu *vcpu, int num, ulong val) static inline ulong kvmppc_get_gpr(struct kvm_vcpu *vcpu, int num) { - if ( num < 14 ) - return to_svcpu(vcpu)->gpr[num]; - else + if ( num < 14 ) { + struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); + ulong r = svcpu->gpr[num]; + svcpu_put(svcpu); + return r; + } else return vcpu->arch.gpr[num]; } static inline void kvmppc_set_cr(struct kvm_vcpu *vcpu, u32 val) { - to_svcpu(vcpu)->cr = val; + struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); + svcpu->cr = val; + svcpu_put(svcpu); to_book3s(vcpu)->shadow_vcpu->cr = val; } static inline u32 kvmppc_get_cr(struct kvm_vcpu *vcpu) { - return to_svcpu(vcpu)->cr; + struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); + u32 r; + r = svcpu->cr; + svcpu_put(svcpu); + return r; } static inline void kvmppc_set_xer(struct kvm_vcpu *vcpu, u32 val) { - to_svcpu(vcpu)->xer = val; + struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); + svcpu->xer = val; to_book3s(vcpu)->shadow_vcpu->xer = val; + svcpu_put(svcpu); } static inline u32 kvmppc_get_xer(struct kvm_vcpu *vcpu) { - return to_svcpu(vcpu)->xer; + struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); + u32 r; + r = svcpu->xer; + svcpu_put(svcpu); + return r; } static inline void kvmppc_set_ctr(struct kvm_vcpu *vcpu, ulong val) { - to_svcpu(vcpu)->ctr = val; + struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); + svcpu->ctr = val; + svcpu_put(svcpu); } static inline ulong kvmppc_get_ctr(struct kvm_vcpu *vcpu) { - return to_svcpu(vcpu)->ctr; + struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); + ulong r; + r = svcpu->ctr; + svcpu_put(svcpu); + return r; } static inline void kvmppc_set_lr(struct kvm_vcpu *vcpu, ulong val) { - to_svcpu(vcpu)->lr = val; + struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); + svcpu->lr = val; + svcpu_put(svcpu); } static inline ulong kvmppc_get_lr(struct kvm_vcpu *vcpu) { - return to_svcpu(vcpu)->lr; + struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); + ulong r; + r = svcpu->lr; + svcpu_put(svcpu); + return r; } static inline void kvmppc_set_pc(struct kvm_vcpu *vcpu, ulong val) { - to_svcpu(vcpu)->pc = val; + struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); + svcpu->pc = val; + svcpu_put(svcpu); } static inline ulong kvmppc_get_pc(struct kvm_vcpu *vcpu) { - return to_svcpu(vcpu)->pc; + struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); + ulong r; + r = svcpu->pc; + svcpu_put(svcpu); + return r; } static inline u32 kvmppc_get_last_inst(struct kvm_vcpu *vcpu) { ulong pc = kvmppc_get_pc(vcpu); - struct kvmppc_book3s_shadow_vcpu *svcpu = to_svcpu(vcpu); + struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); + u32 r; /* Load the instruction manually if it failed to do so in the * exit path */ if (svcpu->last_inst == KVM_INST_FETCH_FAILED) kvmppc_ld(vcpu, &pc, sizeof(u32), &svcpu->last_inst, false); - return svcpu->last_inst; + r = svcpu->last_inst; + svcpu_put(svcpu); + return r; } static inline ulong kvmppc_get_fault_dar(struct kvm_vcpu *vcpu) { - return to_svcpu(vcpu)->fault_dar; + struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); + ulong r; + r = svcpu->fault_dar; + svcpu_put(svcpu); + return r; } static inline bool kvmppc_critical_section(struct kvm_vcpu *vcpu) -- cgit v1.2.3-70-g09d2