xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
派生 0
代码 工单 合并请求 工作流 软件包 项目 发布 百科 活动

KVM: PPC: Use get/set for to_svcpu to help preemption

浏览代码 
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 <joerg@alea.gnuu.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
这个提交包含在：
Alexander Graf
2011-12-09 14:44:13 +01:00
提交者 Avi Kivity
父节点 d33ad328c0
当前提交 468a12c2b5
共修改 8 个文件，包含 181 行新增和 71 行删除
下载 Patch 文件 下载 Diff 文件 展开所有文件 折叠所有文件

62
arch/powerpc/kvm/book3s_pr.c
查看文件

@@ -56,10 +56,12 @@ static int kvmppc_handle_ext(struct kvm_vcpu *vcpu, unsigned int exit_nr,
void kvmppc_core_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
#ifdef CONFIG_PPC_BOOK3S_64
memcpy(to_svcpu(vcpu)->slb, to_book3s(vcpu)->slb_shadow, sizeof(to_svcpu(vcpu)->slb));
struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
memcpy(svcpu->slb, to_book3s(vcpu)->slb_shadow, sizeof(svcpu->slb));
memcpy(&get_paca()->shadow_vcpu, to_book3s(vcpu)->shadow_vcpu,
sizeof(get_paca()->shadow_vcpu));
to_svcpu(vcpu)->slb_max = to_book3s(vcpu)->slb_shadow_max;
svcpu->slb_max = to_book3s(vcpu)->slb_shadow_max;
svcpu_put(svcpu);
#endif
#ifdef CONFIG_PPC_BOOK3S_32
@@ -70,10 +72,12 @@ void kvmppc_core_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
void kvmppc_core_vcpu_put(struct kvm_vcpu *vcpu)
{
#ifdef CONFIG_PPC_BOOK3S_64
memcpy(to_book3s(vcpu)->slb_shadow, to_svcpu(vcpu)->slb, sizeof(to_svcpu(vcpu)->slb));
struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
memcpy(to_book3s(vcpu)->slb_shadow, svcpu->slb, sizeof(svcpu->slb));
memcpy(to_book3s(vcpu)->shadow_vcpu, &get_paca()->shadow_vcpu,
sizeof(get_paca()->shadow_vcpu));
to_book3s(vcpu)->slb_shadow_max = to_svcpu(vcpu)->slb_max;
to_book3s(vcpu)->slb_shadow_max = svcpu->slb_max;
svcpu_put(svcpu);
#endif
kvmppc_giveup_ext(vcpu, MSR_FP);
@@ -308,19 +312,22 @@ int kvmppc_handle_pagefault(struct kvm_run *run, struct kvm_vcpu *vcpu,
if (page_found == -ENOENT) {
/* Page not found in guest PTE entries */
struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
vcpu->arch.shared->dar = kvmppc_get_fault_dar(vcpu);
vcpu->arch.shared->dsisr = to_svcpu(vcpu)->fault_dsisr;
vcpu->arch.shared->dsisr = svcpu->fault_dsisr;
vcpu->arch.shared->msr |=
(to_svcpu(vcpu)->shadow_srr1 & 0x00000000f8000000ULL);
(svcpu->shadow_srr1 & 0x00000000f8000000ULL);
svcpu_put(svcpu);
kvmppc_book3s_queue_irqprio(vcpu, vec);
} else if (page_found == -EPERM) {
/* Storage protection */
struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
vcpu->arch.shared->dar = kvmppc_get_fault_dar(vcpu);
vcpu->arch.shared->dsisr =
to_svcpu(vcpu)->fault_dsisr & ~DSISR_NOHPTE;
vcpu->arch.shared->dsisr = svcpu->fault_dsisr & ~DSISR_NOHPTE;
vcpu->arch.shared->dsisr |= DSISR_PROTFAULT;
vcpu->arch.shared->msr |=
(to_svcpu(vcpu)->shadow_srr1 & 0x00000000f8000000ULL);
svcpu->shadow_srr1 & 0x00000000f8000000ULL;
svcpu_put(svcpu);
kvmppc_book3s_queue_irqprio(vcpu, vec);
} else if (page_found == -EINVAL) {
/* Page not found in guest SLB */
@@ -521,21 +528,25 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu,
kvm_resched(vcpu);
switch (exit_nr) {
case BOOK3S_INTERRUPT_INST_STORAGE:
{
struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
ulong shadow_srr1 = svcpu->shadow_srr1;
vcpu->stat.pf_instruc++;
#ifdef CONFIG_PPC_BOOK3S_32
/* We set segments as unused segments when invalidating them. So
* treat the respective fault as segment fault. */
if (to_svcpu(vcpu)->sr[kvmppc_get_pc(vcpu) >> SID_SHIFT]
== SR_INVALID) {
if (svcpu->sr[kvmppc_get_pc(vcpu) >> SID_SHIFT] == SR_INVALID) {
kvmppc_mmu_map_segment(vcpu, kvmppc_get_pc(vcpu));
r = RESUME_GUEST;
svcpu_put(svcpu);
break;
}
#endif
svcpu_put(svcpu);
/* only care about PTEG not found errors, but leave NX alone */
if (to_svcpu(vcpu)->shadow_srr1 & 0x40000000) {
if (shadow_srr1 & 0x40000000) {
r = kvmppc_handle_pagefault(run, vcpu, kvmppc_get_pc(vcpu), exit_nr);
vcpu->stat.sp_instruc++;
} else if (vcpu->arch.mmu.is_dcbz32(vcpu) &&
@@ -548,33 +559,37 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu,
kvmppc_mmu_pte_flush(vcpu, kvmppc_get_pc(vcpu), ~0xFFFUL);
r = RESUME_GUEST;
} else {
vcpu->arch.shared->msr |=
to_svcpu(vcpu)->shadow_srr1 & 0x58000000;
vcpu->arch.shared->msr |= shadow_srr1 & 0x58000000;
kvmppc_book3s_queue_irqprio(vcpu, exit_nr);
r = RESUME_GUEST;
}
break;
}
case BOOK3S_INTERRUPT_DATA_STORAGE:
{
ulong dar = kvmppc_get_fault_dar(vcpu);
struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
u32 fault_dsisr = svcpu->fault_dsisr;
vcpu->stat.pf_storage++;
#ifdef CONFIG_PPC_BOOK3S_32
/* We set segments as unused segments when invalidating them. So
* treat the respective fault as segment fault. */
if ((to_svcpu(vcpu)->sr[dar >> SID_SHIFT]) == SR_INVALID) {
if ((svcpu->sr[dar >> SID_SHIFT]) == SR_INVALID) {
kvmppc_mmu_map_segment(vcpu, dar);
r = RESUME_GUEST;
svcpu_put(svcpu);
break;
}
#endif
svcpu_put(svcpu);
/* The only case we need to handle is missing shadow PTEs */
if (to_svcpu(vcpu)->fault_dsisr & DSISR_NOHPTE) {
if (fault_dsisr & DSISR_NOHPTE) {
r = kvmppc_handle_pagefault(run, vcpu, dar, exit_nr);
} else {
vcpu->arch.shared->dar = dar;
vcpu->arch.shared->dsisr = to_svcpu(vcpu)->fault_dsisr;
vcpu->arch.shared->dsisr = fault_dsisr;
kvmppc_book3s_queue_irqprio(vcpu, exit_nr);
r = RESUME_GUEST;
}
@@ -610,10 +625,13 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu,
case BOOK3S_INTERRUPT_PROGRAM:
{
enum emulation_result er;
struct kvmppc_book3s_shadow_vcpu *svcpu;
ulong flags;
program_interrupt:
flags = to_svcpu(vcpu)->shadow_srr1 & 0x1f0000ull;
svcpu = svcpu_get(vcpu);
flags = svcpu->shadow_srr1 & 0x1f0000ull;
svcpu_put(svcpu);
if (vcpu->arch.shared->msr & MSR_PR) {
#ifdef EXIT_DEBUG
@@ -741,14 +759,18 @@ program_interrupt:
r = RESUME_GUEST;
break;
default:
{
struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
ulong shadow_srr1 = svcpu->shadow_srr1;
svcpu_put(svcpu);
/* Ugh - bork here! What did we get? */
printk(KERN_EMERG "exit_nr=0x%x | pc=0x%lx | msr=0x%lx\n",
exit_nr, kvmppc_get_pc(vcpu), to_svcpu(vcpu)->shadow_srr1);
exit_nr, kvmppc_get_pc(vcpu), shadow_srr1);
r = RESUME_HOST;
BUG();
break;
}
}
if (!(r & RESUME_HOST)) {
/* To avoid clobbering exit_reason, only check for signals if