| Message ID | 20211108111032.24457-6-likexu@tencent.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Use static_call for kvm_pmu_ops | expand |
s/tagged/tag On Mon, Nov 08, 2021, Like Xu wrote: > From: Like Xu <likexu@tencent.com> > > The pmu_ops should be moved to kvm_x86_init_ops and tagged as __initdata. State what the patch does, not what "should" be done. Now that pmu_ops is copied by value during kvm_arch_hardware_setup(), move the pointer to kvm_x86_init_ops and tag implementations as __initdata to make the implementations unreachable once KVM is loaded, e.g. to make it harder to sneak in post-init modification bugs. > That'll save those precious few bytes, and more importantly make > the original ops unreachable, i.e. make it harder to sneak in post-init > modification bugs. > > Suggested-by: Sean Christopherson <seanjc@google.com> > Signed-off-by: Like Xu <likexu@tencent.com> > --- > arch/x86/include/asm/kvm_host.h | 4 ++-- > arch/x86/kvm/svm/pmu.c | 2 +- > arch/x86/kvm/svm/svm.c | 2 +- > arch/x86/kvm/vmx/pmu_intel.c | 2 +- > arch/x86/kvm/vmx/vmx.c | 2 +- > arch/x86/kvm/x86.c | 2 +- > 6 files changed, 7 insertions(+), 7 deletions(-) > > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > index c2d4ee2973c5..00760a3ac88c 100644 > --- a/arch/x86/include/asm/kvm_host.h > +++ b/arch/x86/include/asm/kvm_host.h > @@ -1436,8 +1436,7 @@ struct kvm_x86_ops { > int cpu_dirty_log_size; > void (*update_cpu_dirty_logging)(struct kvm_vcpu *vcpu); > > - /* pmu operations of sub-arch */ > - const struct kvm_pmu_ops *pmu_ops; > + /* nested operations of sub-arch */ No need for the new comment. > const struct kvm_x86_nested_ops *nested_ops; > > /* Nits aside, Reviewed-by: Sean Christopherson <seanjc@google.com> I'd also be a-ok squashing this with the copy-by-value patch.
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index c2d4ee2973c5..00760a3ac88c 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1436,8 +1436,7 @@ struct kvm_x86_ops { int cpu_dirty_log_size; void (*update_cpu_dirty_logging)(struct kvm_vcpu *vcpu); - /* pmu operations of sub-arch */ - const struct kvm_pmu_ops *pmu_ops; + /* nested operations of sub-arch */ const struct kvm_x86_nested_ops *nested_ops; /* @@ -1516,6 +1515,7 @@ struct kvm_x86_init_ops { int (*hardware_setup)(void); struct kvm_x86_ops *runtime_ops; + struct kvm_pmu_ops *pmu_ops; }; struct kvm_arch_async_pf { diff --git a/arch/x86/kvm/svm/pmu.c b/arch/x86/kvm/svm/pmu.c index fdf587f19c5f..4554cbc3820c 100644 --- a/arch/x86/kvm/svm/pmu.c +++ b/arch/x86/kvm/svm/pmu.c @@ -319,7 +319,7 @@ static void amd_pmu_reset(struct kvm_vcpu *vcpu) } } -struct kvm_pmu_ops amd_pmu_ops = { +struct kvm_pmu_ops amd_pmu_ops __initdata = { .find_arch_event = amd_find_arch_event, .find_fixed_event = amd_find_fixed_event, .pmc_is_enabled = amd_pmc_is_enabled, diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 21bb81710e0f..8834d7d2b991 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -4681,7 +4681,6 @@ static struct kvm_x86_ops svm_x86_ops __initdata = { .sched_in = svm_sched_in, - .pmu_ops = &amd_pmu_ops, .nested_ops = &svm_nested_ops, .deliver_posted_interrupt = svm_deliver_avic_intr, @@ -4717,6 +4716,7 @@ static struct kvm_x86_init_ops svm_init_ops __initdata = { .check_processor_compatibility = svm_check_processor_compat, .runtime_ops = &svm_x86_ops, + .pmu_ops = &amd_pmu_ops, }; static int __init svm_init(void) diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c index b8e0d21b7c8a..c0b905d032c8 100644 --- a/arch/x86/kvm/vmx/pmu_intel.c +++ b/arch/x86/kvm/vmx/pmu_intel.c @@ -703,7 +703,7 @@ static void intel_pmu_cleanup(struct kvm_vcpu *vcpu) intel_pmu_release_guest_lbr_event(vcpu); } -struct kvm_pmu_ops intel_pmu_ops = { +struct kvm_pmu_ops intel_pmu_ops __initdata = { .find_arch_event = intel_find_arch_event, .find_fixed_event = intel_find_fixed_event, .pmc_is_enabled = intel_pmc_is_enabled, diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 71f54d85f104..ce787d2e8e08 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -7680,7 +7680,6 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = { .pre_block = vmx_pre_block, .post_block = vmx_post_block, - .pmu_ops = &intel_pmu_ops, .nested_ops = &vmx_nested_ops, .update_pi_irte = pi_update_irte, @@ -7922,6 +7921,7 @@ static struct kvm_x86_init_ops vmx_init_ops __initdata = { .hardware_setup = hardware_setup, .runtime_ops = &vmx_x86_ops, + .pmu_ops = &intel_pmu_ops, }; static void vmx_cleanup_l1d_flush(void) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index ca9a76abb6ba..70dc8f41329c 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -11323,7 +11323,7 @@ int kvm_arch_hardware_setup(void *opaque) return r; memcpy(&kvm_x86_ops, ops->runtime_ops, sizeof(kvm_x86_ops)); - memcpy(&kvm_pmu_ops, kvm_x86_ops.pmu_ops, sizeof(kvm_pmu_ops)); + memcpy(&kvm_pmu_ops, ops->pmu_ops, sizeof(kvm_pmu_ops)); kvm_ops_static_call_update(); if (!kvm_cpu_cap_has(X86_FEATURE_XSAVES))