From patchwork Wed Feb 9 07:41:02 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chao Gao X-Patchwork-Id: 12739733 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B6241C433EF for ; Wed, 9 Feb 2022 07:41:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238960AbiBIHli (ORCPT ); Wed, 9 Feb 2022 02:41:38 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39628 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238886AbiBIHlf (ORCPT ); Wed, 9 Feb 2022 02:41:35 -0500 Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2A62CC0613CA; Tue, 8 Feb 2022 23:41:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1644392499; x=1675928499; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=vaTrRgufDi0pw8hbdS+IY/vlRc9TqpU/H7WiltbW1KY=; b=mKBGBQGVijIeNgNrhyeQIPMihM8caiIShjR/BdneqMvIxHCdmL/8kSCY aw5WMiQWohMex43f4fJ2Hnafcx2fhIfj9GBZuJfTmCEzHSs2mLAT+D15s VFG2j3bYGIm0tVdGiiH4pWNKYwbtC09rwTD96tPZJtSZyXbMtG7dwS5fJ ub2+Ywq6/cJYGtTej5AkMC0hIxttCpkbZ1pWmFClscX1LSF+LqY4bv7f2 BaGbcHCvHWqEAjQAsmki/JNK15lnsP3v3+UGlt41UnrRxyHI1/2j/wUQO OYauMc6+9EiKBBXJp26UBGLSVu8XUbtS1d2ciVmmxdcp1qEIFD6ogUdWc g==; X-IronPort-AV: E=McAfee;i="6200,9189,10252"; a="247980724" X-IronPort-AV: E=Sophos;i="5.88,355,1635231600"; d="scan'208";a="247980724" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Feb 2022 23:41:39 -0800 X-IronPort-AV: E=Sophos;i="5.88,355,1635231600"; d="scan'208";a="540984552" Received: from hyperv-sh4.sh.intel.com ([10.239.48.22]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Feb 2022 23:41:35 -0800 From: Chao Gao To: kvm@vger.kernel.org, seanjc@google.com, pbonzini@redhat.com, kevin.tian@intel.com, tglx@linutronix.de Cc: Chao Gao , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , linux-kernel@vger.kernel.org Subject: [PATCH v3 1/5] KVM: x86: Move check_processor_compatibility from init ops to runtime ops Date: Wed, 9 Feb 2022 15:41:02 +0800 Message-Id: <20220209074109.453116-2-chao.gao@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220209074109.453116-1-chao.gao@intel.com> References: <20220209074109.453116-1-chao.gao@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org so that KVM can do compatibility checks on hotplugged CPUs. Drop __init from check_processor_compatibility() and its callees. use a static_call() to invoke .check_processor_compatibility. Opportunistically rename {svm,vmx}_check_processor_compat to conform to the naming convention of fields of kvm_x86_ops. Signed-off-by: Chao Gao Reviewed-by: Sean Christopherson --- arch/x86/include/asm/kvm-x86-ops.h | 1 + arch/x86/include/asm/kvm_host.h | 2 +- arch/x86/kvm/svm/svm.c | 4 ++-- arch/x86/kvm/vmx/evmcs.c | 2 +- arch/x86/kvm/vmx/evmcs.h | 2 +- arch/x86/kvm/vmx/vmx.c | 12 ++++++------ arch/x86/kvm/x86.c | 3 +-- 7 files changed, 13 insertions(+), 13 deletions(-) diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h index 9e37dc3d8863..08494f172e2e 100644 --- a/arch/x86/include/asm/kvm-x86-ops.h +++ b/arch/x86/include/asm/kvm-x86-ops.h @@ -125,6 +125,7 @@ KVM_X86_OP_NULL(migrate_timers) KVM_X86_OP(msr_filter_changed) KVM_X86_OP_NULL(complete_emulated_msr) KVM_X86_OP(vcpu_deliver_sipi_vector) +KVM_X86_OP(check_processor_compatibility) #undef KVM_X86_OP #undef KVM_X86_OP_NULL diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index c371ee7e45f7..f65ccb5597bc 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1314,6 +1314,7 @@ static inline u16 kvm_lapic_irq_dest_mode(bool dest_mode_logical) struct kvm_x86_ops { const char *name; + int (*check_processor_compatibility)(void); int (*hardware_enable)(void); void (*hardware_disable)(void); void (*hardware_unsetup)(void); @@ -1518,7 +1519,6 @@ struct kvm_x86_nested_ops { struct kvm_x86_init_ops { int (*cpu_has_kvm_support)(void); int (*disabled_by_bios)(void); - int (*check_processor_compatibility)(void); int (*hardware_setup)(void); struct kvm_x86_ops *runtime_ops; diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 975be872cd1a..df20d50526ce 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -3858,7 +3858,7 @@ svm_patch_hypercall(struct kvm_vcpu *vcpu, unsigned char *hypercall) hypercall[2] = 0xd9; } -static int __init svm_check_processor_compat(void) +static int svm_check_processor_compatibility(void) { return 0; } @@ -4468,6 +4468,7 @@ static struct kvm_x86_ops svm_x86_ops __initdata = { .name = "kvm_amd", .hardware_unsetup = svm_hardware_unsetup, + .check_processor_compatibility = svm_check_processor_compatibility, .hardware_enable = svm_hardware_enable, .hardware_disable = svm_hardware_disable, .cpu_has_accelerated_tpr = svm_cpu_has_accelerated_tpr, @@ -4839,7 +4840,6 @@ static struct kvm_x86_init_ops svm_init_ops __initdata = { .cpu_has_kvm_support = has_svm, .disabled_by_bios = is_disabled, .hardware_setup = svm_hardware_setup, - .check_processor_compatibility = svm_check_processor_compat, .runtime_ops = &svm_x86_ops, }; diff --git a/arch/x86/kvm/vmx/evmcs.c b/arch/x86/kvm/vmx/evmcs.c index 87e3dc10edf4..a2a4c87d0558 100644 --- a/arch/x86/kvm/vmx/evmcs.c +++ b/arch/x86/kvm/vmx/evmcs.c @@ -295,7 +295,7 @@ const struct evmcs_field vmcs_field_to_evmcs_1[] = { const unsigned int nr_evmcs_1_fields = ARRAY_SIZE(vmcs_field_to_evmcs_1); #if IS_ENABLED(CONFIG_HYPERV) -__init void evmcs_sanitize_exec_ctrls(struct vmcs_config *vmcs_conf) +void evmcs_sanitize_exec_ctrls(struct vmcs_config *vmcs_conf) { vmcs_conf->pin_based_exec_ctrl &= ~EVMCS1_UNSUPPORTED_PINCTRL; vmcs_conf->cpu_based_2nd_exec_ctrl &= ~EVMCS1_UNSUPPORTED_2NDEXEC; diff --git a/arch/x86/kvm/vmx/evmcs.h b/arch/x86/kvm/vmx/evmcs.h index 8d70f9aea94b..3fd4cc44d8ad 100644 --- a/arch/x86/kvm/vmx/evmcs.h +++ b/arch/x86/kvm/vmx/evmcs.h @@ -211,7 +211,7 @@ static inline void evmcs_load(u64 phys_addr) vp_ap->enlighten_vmentry = 1; } -__init void evmcs_sanitize_exec_ctrls(struct vmcs_config *vmcs_conf); +void evmcs_sanitize_exec_ctrls(struct vmcs_config *vmcs_conf); #else /* !IS_ENABLED(CONFIG_HYPERV) */ static __always_inline void evmcs_write64(unsigned long field, u64 value) {} static inline void evmcs_write32(unsigned long field, u32 value) {} diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 8ac5a6fa7720..fc94d7139f69 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -2403,8 +2403,8 @@ static bool cpu_has_sgx(void) return cpuid_eax(0) >= 0x12 && (cpuid_eax(0x12) & BIT(0)); } -static __init int adjust_vmx_controls(u32 ctl_min, u32 ctl_opt, - u32 msr, u32 *result) +static int adjust_vmx_controls(u32 ctl_min, u32 ctl_opt, + u32 msr, u32 *result) { u32 vmx_msr_low, vmx_msr_high; u32 ctl = ctl_min | ctl_opt; @@ -2422,8 +2422,8 @@ static __init int adjust_vmx_controls(u32 ctl_min, u32 ctl_opt, return 0; } -static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf, - struct vmx_capability *vmx_cap) +static int setup_vmcs_config(struct vmcs_config *vmcs_conf, + struct vmx_capability *vmx_cap) { u32 vmx_msr_low, vmx_msr_high; u32 min, opt, min2, opt2; @@ -7116,7 +7116,7 @@ static int vmx_vm_init(struct kvm *kvm) return 0; } -static int __init vmx_check_processor_compat(void) +static int vmx_check_processor_compatibility(void) { struct vmcs_config vmcs_conf; struct vmx_capability vmx_cap; @@ -7709,6 +7709,7 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = { .hardware_unsetup = vmx_hardware_unsetup, + .check_processor_compatibility = vmx_check_processor_compatibility, .hardware_enable = vmx_hardware_enable, .hardware_disable = vmx_hardware_disable, .cpu_has_accelerated_tpr = vmx_cpu_has_accelerated_tpr, @@ -8043,7 +8044,6 @@ static __init int hardware_setup(void) static struct kvm_x86_init_ops vmx_init_ops __initdata = { .cpu_has_kvm_support = cpu_has_kvm_support, .disabled_by_bios = vmx_disabled_by_bios, - .check_processor_compatibility = vmx_check_processor_compat, .hardware_setup = hardware_setup, .runtime_ops = &vmx_x86_ops, diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 6f69f3e3635e..b71549a52ae0 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -11551,7 +11551,6 @@ void kvm_arch_hardware_unsetup(void) int kvm_arch_check_processor_compat(void *opaque) { struct cpuinfo_x86 *c = &cpu_data(smp_processor_id()); - struct kvm_x86_init_ops *ops = opaque; WARN_ON(!irqs_disabled()); @@ -11559,7 +11558,7 @@ int kvm_arch_check_processor_compat(void *opaque) __cr4_reserved_bits(cpu_has, &boot_cpu_data)) return -EIO; - return ops->check_processor_compatibility(); + return static_call(kvm_x86_check_processor_compatibility)(); } bool kvm_vcpu_is_reset_bsp(struct kvm_vcpu *vcpu) From patchwork Wed Feb 9 07:41:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chao Gao X-Patchwork-Id: 12739734 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1CA54C43217 for ; Wed, 9 Feb 2022 07:42:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239468AbiBIHm3 (ORCPT ); Wed, 9 Feb 2022 02:42:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39774 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238892AbiBIHmN (ORCPT ); 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08 Feb 2022 23:41:51 -0800 X-IronPort-AV: E=Sophos;i="5.88,355,1635231600"; d="scan'208";a="540984661" Received: from hyperv-sh4.sh.intel.com ([10.239.48.22]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Feb 2022 23:41:40 -0800 From: Chao Gao To: kvm@vger.kernel.org, seanjc@google.com, pbonzini@redhat.com, kevin.tian@intel.com, tglx@linutronix.de Cc: Chao Gao , Marc Zyngier , James Morse , Alexandru Elisei , Suzuki K Poulose , Catalin Marinas , Will Deacon , Huacai Chen , Aleksandar Markovic , Thomas Bogendoerfer , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Anup Patel , Atish Patra , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , David Hildenbrand , Claudio Imbrenda , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , "Maciej S. Szmigiero" , Ravi Bangoria , Juergen Gross , Fabiano Rosas , Bharata B Rao , Nick Desaulniers , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org Subject: [PATCH v3 2/5] Partially revert "KVM: Pass kvm_init()'s opaque param to additional arch funcs" Date: Wed, 9 Feb 2022 15:41:03 +0800 Message-Id: <20220209074109.453116-3-chao.gao@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220209074109.453116-1-chao.gao@intel.com> References: <20220209074109.453116-1-chao.gao@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This partially reverts commit b99040853738 ("KVM: Pass kvm_init()'s opaque param to additional arch funcs") remove opaque from kvm_arch_check_processor_compat because no one uses this opaque now. Address conflicts for ARM (due to file movement) and manually handle RISC-V which comes after the commit. And changes about kvm_arch_hardware_setup() in original commit are still needed so they are not reverted. Signed-off-by: Chao Gao Reviewed-by: Sean Christopherson --- arch/arm64/kvm/arm.c | 2 +- arch/mips/kvm/mips.c | 2 +- arch/powerpc/kvm/powerpc.c | 2 +- arch/riscv/kvm/main.c | 2 +- arch/s390/kvm/kvm-s390.c | 2 +- arch/x86/kvm/x86.c | 2 +- include/linux/kvm_host.h | 2 +- virt/kvm/kvm_main.c | 16 +++------------- 8 files changed, 10 insertions(+), 20 deletions(-) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index a069d5925f77..60494c576242 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -73,7 +73,7 @@ int kvm_arch_hardware_setup(void *opaque) return 0; } -int kvm_arch_check_processor_compat(void *opaque) +int kvm_arch_check_processor_compat(void) { return 0; } diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c index a25e0b73ee70..092d09fb6a7e 100644 --- a/arch/mips/kvm/mips.c +++ b/arch/mips/kvm/mips.c @@ -140,7 +140,7 @@ int kvm_arch_hardware_setup(void *opaque) return 0; } -int kvm_arch_check_processor_compat(void *opaque) +int kvm_arch_check_processor_compat(void) { return 0; } diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 2ad0ccd202d5..30c817f3fa0c 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -423,7 +423,7 @@ int kvm_arch_hardware_setup(void *opaque) return 0; } -int kvm_arch_check_processor_compat(void *opaque) +int kvm_arch_check_processor_compat(void) { return kvmppc_core_check_processor_compat(); } diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c index 2e5ca43c8c49..992877e78393 100644 --- a/arch/riscv/kvm/main.c +++ b/arch/riscv/kvm/main.c @@ -20,7 +20,7 @@ long kvm_arch_dev_ioctl(struct file *filp, return -EINVAL; } -int kvm_arch_check_processor_compat(void *opaque) +int kvm_arch_check_processor_compat(void) { return 0; } diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 9c6d45d0d345..99c70d881cb6 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -252,7 +252,7 @@ int kvm_arch_hardware_enable(void) return 0; } -int kvm_arch_check_processor_compat(void *opaque) +int kvm_arch_check_processor_compat(void) { return 0; } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index b71549a52ae0..e9777ffc50c2 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -11548,7 +11548,7 @@ void kvm_arch_hardware_unsetup(void) static_call(kvm_x86_hardware_unsetup)(); } -int kvm_arch_check_processor_compat(void *opaque) +int kvm_arch_check_processor_compat(void) { struct cpuinfo_x86 *c = &cpu_data(smp_processor_id()); diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index b3810976a27f..3c7b654e43fb 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1413,7 +1413,7 @@ int kvm_arch_hardware_enable(void); void kvm_arch_hardware_disable(void); int kvm_arch_hardware_setup(void *opaque); void kvm_arch_hardware_unsetup(void); -int kvm_arch_check_processor_compat(void *opaque); +int kvm_arch_check_processor_compat(void); int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu); bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu); int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 034c567a680c..be614a6325e4 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -5599,22 +5599,14 @@ struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void) return &kvm_running_vcpu; } -struct kvm_cpu_compat_check { - void *opaque; - int *ret; -}; - -static void check_processor_compat(void *data) +static void check_processor_compat(void *rtn) { - struct kvm_cpu_compat_check *c = data; - - *c->ret = kvm_arch_check_processor_compat(c->opaque); + *(int *)rtn = kvm_arch_check_processor_compat(); } int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align, struct module *module) { - struct kvm_cpu_compat_check c; int r; int cpu; @@ -5642,10 +5634,8 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align, if (r < 0) goto out_free_1; - c.ret = &r; - c.opaque = opaque; for_each_online_cpu(cpu) { - smp_call_function_single(cpu, check_processor_compat, &c, 1); + smp_call_function_single(cpu, check_processor_compat, &r, 1); if (r < 0) goto out_free_2; } From patchwork Wed Feb 9 07:41:04 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chao Gao X-Patchwork-Id: 12739735 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 446BFC433EF for ; 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X-IronPort-AV: E=McAfee;i="6200,9189,10252"; a="248907305" X-IronPort-AV: E=Sophos;i="5.88,355,1635231600"; d="scan'208";a="248907305" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Feb 2022 23:41:53 -0800 X-IronPort-AV: E=Sophos;i="5.88,355,1635231600"; d="scan'208";a="540984684" Received: from hyperv-sh4.sh.intel.com ([10.239.48.22]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Feb 2022 23:41:51 -0800 From: Chao Gao To: kvm@vger.kernel.org, seanjc@google.com, pbonzini@redhat.com, kevin.tian@intel.com, tglx@linutronix.de Cc: Chao Gao , linux-kernel@vger.kernel.org Subject: [PATCH v3 3/5] KVM: Provide more information in kernel log if hardware enabling fails Date: Wed, 9 Feb 2022 15:41:04 +0800 Message-Id: <20220209074109.453116-4-chao.gao@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220209074109.453116-1-chao.gao@intel.com> References: <20220209074109.453116-1-chao.gao@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Sean Christopherson Provide the name of the calling function to hardware_enable_nolock() and include it in the error message to provide additional information on exactly what path failed. Opportunistically bump the pr_info() to pr_warn(), failure to enable virtualization support is warn-worthy as _something_ is wrong with the system. Signed-off-by: Sean Christopherson Signed-off-by: Chao Gao --- virt/kvm/kvm_main.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index be614a6325e4..23481fd746aa 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -4833,7 +4833,7 @@ static struct miscdevice kvm_dev = { &kvm_chardev_ops, }; -static void hardware_enable_nolock(void *junk) +static void hardware_enable_nolock(void *caller_name) { int cpu = raw_smp_processor_id(); int r; @@ -4848,7 +4848,8 @@ static void hardware_enable_nolock(void *junk) if (r) { cpumask_clear_cpu(cpu, cpus_hardware_enabled); atomic_inc(&hardware_enable_failed); - pr_info("kvm: enabling virtualization on CPU%d failed\n", cpu); + pr_warn("kvm: enabling virtualization on CPU%d failed during %s()\n", + cpu, (const char *)caller_name); } } @@ -4856,7 +4857,7 @@ static int kvm_starting_cpu(unsigned int cpu) { raw_spin_lock(&kvm_count_lock); if (kvm_usage_count) - hardware_enable_nolock(NULL); + hardware_enable_nolock((void *)__func__); raw_spin_unlock(&kvm_count_lock); return 0; } @@ -4905,7 +4906,7 @@ static int hardware_enable_all(void) kvm_usage_count++; if (kvm_usage_count == 1) { atomic_set(&hardware_enable_failed, 0); - on_each_cpu(hardware_enable_nolock, NULL, 1); + on_each_cpu(hardware_enable_nolock, (void *)__func__, 1); if (atomic_read(&hardware_enable_failed)) { hardware_disable_all_nolock(); @@ -5530,7 +5531,7 @@ static void kvm_resume(void) #ifdef CONFIG_LOCKDEP WARN_ON(lockdep_is_held(&kvm_count_lock)); #endif - hardware_enable_nolock(NULL); + hardware_enable_nolock((void *)__func__); } } From patchwork Wed Feb 9 07:41:05 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chao Gao X-Patchwork-Id: 12739736 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2E533C433F5 for ; Wed, 9 Feb 2022 07:43:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239735AbiBIHmz (ORCPT ); Wed, 9 Feb 2022 02:42:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40162 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239052AbiBIHm0 (ORCPT ); Wed, 9 Feb 2022 02:42:26 -0500 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9F269C05CB8C; Tue, 8 Feb 2022 23:42:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1644392550; x=1675928550; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=7oQ6ZbaKyf2t7+Jw+hgZ1jRXBsKBASTYCG0C9ywN06s=; b=HXM8DYgIgu+HrFUd0SQ/W/J2jWWah/qW4cZV1v9IwuCvgkddlLoet0wq s/B+zBwvdmLF5UYMOMix13Ko3YcDoIs8DivM373dCv39/geZ3Ib48fBhD R0GLY8jcOQ7i3L4L6IMMc5U0tWYu1ITR4f2y72R/lteFrXCedWRRJHtEy Fb3bDsf+dzT4wxaxiA4mFNkQQFrHJzxQAit5A9Q8LZ5LwrAv984Dvs1dz WNEdW2MXj1kdvM7I8g9cyarjvvF1W1ST3JJbmEdGE4QKZ6xAPWlpojG86 dE1h1PjH788r/iFKdYuviQzuXmdK0Rhxf4ErQsMRf/54O+oD2FLpTH+7s w==; X-IronPort-AV: E=McAfee;i="6200,9189,10252"; a="248907359" X-IronPort-AV: E=Sophos;i="5.88,355,1635231600"; d="scan'208";a="248907359" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Feb 2022 23:41:58 -0800 X-IronPort-AV: E=Sophos;i="5.88,355,1635231600"; d="scan'208";a="540984736" Received: from hyperv-sh4.sh.intel.com ([10.239.48.22]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Feb 2022 23:41:54 -0800 From: Chao Gao To: kvm@vger.kernel.org, seanjc@google.com, pbonzini@redhat.com, kevin.tian@intel.com, tglx@linutronix.de Cc: Chao Gao , John Garry , Will Deacon , Qi Liu , Thomas Richter , Shaokun Zhang , Hector Martin , Huang Ying , linux-kernel@vger.kernel.org Subject: [PATCH v3 4/5] KVM: Rename and move CPUHP_AP_KVM_STARTING to ONLINE section Date: Wed, 9 Feb 2022 15:41:05 +0800 Message-Id: <20220209074109.453116-5-chao.gao@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220209074109.453116-1-chao.gao@intel.com> References: <20220209074109.453116-1-chao.gao@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org The CPU STARTING section doesn't allow callbacks to fail. Move KVM's hotplug callback to ONLINE section so that it can abort onlining a CPU in certain cases to avoid potentially breaking VMs running on existing CPUs. For example, when kvm fails to enable hardware virtualization on the hotplugged CPU. Place KVM's hotplug state before CPUHP_AP_SCHED_WAIT_EMPTY as it ensures when offlining a CPU, all user tasks and non-pinned kernel tasks have left the CPU, i.e. there cannot be a vCPU task around. So, it is safe for KVM's CPU offline callback to disable hardware virtualization at that point. Likewise, KVM's online callback can enable hardware virtualization before any vCPU task gets a chance to run on hotplugged CPUs. KVM's CPU hotplug callbacks are renamed as well. Suggested-by: Thomas Gleixner Signed-off-by: Chao Gao Signed-off-by: Marc Zyngier --- include/linux/cpuhotplug.h | 2 +- virt/kvm/kvm_main.c | 30 ++++++++++++++++++++++-------- 2 files changed, 23 insertions(+), 9 deletions(-) diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 773c83730906..14d354c8ce35 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -182,7 +182,6 @@ enum cpuhp_state { CPUHP_AP_CSKY_TIMER_STARTING, CPUHP_AP_TI_GP_TIMER_STARTING, CPUHP_AP_HYPERV_TIMER_STARTING, - CPUHP_AP_KVM_STARTING, CPUHP_AP_KVM_ARM_VGIC_INIT_STARTING, CPUHP_AP_KVM_ARM_VGIC_STARTING, CPUHP_AP_KVM_ARM_TIMER_STARTING, @@ -200,6 +199,7 @@ enum cpuhp_state { /* Online section invoked on the hotplugged CPU from the hotplug thread */ CPUHP_AP_ONLINE_IDLE, + CPUHP_AP_KVM_ONLINE, CPUHP_AP_SCHED_WAIT_EMPTY, CPUHP_AP_SMPBOOT_THREADS, CPUHP_AP_X86_VDSO_VMA_ONLINE, diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 23481fd746aa..f60724736cb1 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -4853,13 +4853,27 @@ static void hardware_enable_nolock(void *caller_name) } } -static int kvm_starting_cpu(unsigned int cpu) +static int kvm_online_cpu(unsigned int cpu) { + int ret = 0; + raw_spin_lock(&kvm_count_lock); - if (kvm_usage_count) + /* + * Abort the CPU online process if hardware virtualization cannot + * be enabled. Otherwise running VMs would encounter unrecoverable + * errors when scheduled to this CPU. + */ + if (kvm_usage_count) { + WARN_ON_ONCE(atomic_read(&hardware_enable_failed)); + hardware_enable_nolock((void *)__func__); + if (atomic_read(&hardware_enable_failed)) { + atomic_set(&hardware_enable_failed, 0); + ret = -EIO; + } + } raw_spin_unlock(&kvm_count_lock); - return 0; + return ret; } static void hardware_disable_nolock(void *junk) @@ -4872,7 +4886,7 @@ static void hardware_disable_nolock(void *junk) kvm_arch_hardware_disable(); } -static int kvm_dying_cpu(unsigned int cpu) +static int kvm_offline_cpu(unsigned int cpu) { raw_spin_lock(&kvm_count_lock); if (kvm_usage_count) @@ -5641,8 +5655,8 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align, goto out_free_2; } - r = cpuhp_setup_state_nocalls(CPUHP_AP_KVM_STARTING, "kvm/cpu:starting", - kvm_starting_cpu, kvm_dying_cpu); + r = cpuhp_setup_state_nocalls(CPUHP_AP_KVM_ONLINE, "kvm/cpu:online", + kvm_online_cpu, kvm_offline_cpu); if (r) goto out_free_2; register_reboot_notifier(&kvm_reboot_notifier); @@ -5705,7 +5719,7 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align, kmem_cache_destroy(kvm_vcpu_cache); out_free_3: unregister_reboot_notifier(&kvm_reboot_notifier); - cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING); + cpuhp_remove_state_nocalls(CPUHP_AP_KVM_ONLINE); out_free_2: kvm_arch_hardware_unsetup(); out_free_1: @@ -5731,7 +5745,7 @@ void kvm_exit(void) kvm_async_pf_deinit(); unregister_syscore_ops(&kvm_syscore_ops); unregister_reboot_notifier(&kvm_reboot_notifier); - cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING); + cpuhp_remove_state_nocalls(CPUHP_AP_KVM_ONLINE); on_each_cpu(hardware_disable_nolock, NULL, 1); kvm_arch_hardware_unsetup(); kvm_arch_exit(); From patchwork Wed Feb 9 07:41:06 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chao Gao X-Patchwork-Id: 12739737 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0EEDFC4332F for ; Wed, 9 Feb 2022 07:43:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239970AbiBIHm6 (ORCPT ); Wed, 9 Feb 2022 02:42:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39776 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239356AbiBIHm2 (ORCPT ); Wed, 9 Feb 2022 02:42:28 -0500 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9ACCDC05CB90; Tue, 8 Feb 2022 23:42:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1644392551; x=1675928551; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=/DKEaaHy2+BNSJa66JF603f8foYnTYwUDIcXvB3wl7g=; b=frLs+1gvHw9HyVf2UAKu6JB6h3OtO2KmlwR+Ezu4W8COdGU8ZG9aID++ aGNrRvnsZl8bPWO72dGZVhg7xP0tfUDhW7+rviFmGj84HglI+ckDHtFet XdYqwqdsxchgGKIVHYBDr0mMTIMP5XEvoQpq4a286aTamRq9iwPqjAmtG c2rRP0M/LAwbonCSuc/f/Kx1JyZdJsJA5Y/9YZwGeVedlG8npcIVR4jOx JN5LlGMXIljGbeP066kCyZS0p1u4rMlIZKQ5cJCKIvKLF+JRtL2UZlXab ePGREZ64F+tSSDSiwsngEMIkkHKmmVdfCIiK2IPWqO4bFjbpyQZxnMCeo A==; X-IronPort-AV: E=McAfee;i="6200,9189,10252"; a="248907365" X-IronPort-AV: E=Sophos;i="5.88,355,1635231600"; d="scan'208";a="248907365" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Feb 2022 23:42:02 -0800 X-IronPort-AV: E=Sophos;i="5.88,355,1635231600"; d="scan'208";a="540984776" Received: from hyperv-sh4.sh.intel.com ([10.239.48.22]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Feb 2022 23:41:58 -0800 From: Chao Gao To: kvm@vger.kernel.org, seanjc@google.com, pbonzini@redhat.com, kevin.tian@intel.com, tglx@linutronix.de Cc: Chao Gao , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , linux-kernel@vger.kernel.org Subject: [PATCH v3 5/5] KVM: Do compatibility checks on hotplugged CPUs Date: Wed, 9 Feb 2022 15:41:06 +0800 Message-Id: <20220209074109.453116-6-chao.gao@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220209074109.453116-1-chao.gao@intel.com> References: <20220209074109.453116-1-chao.gao@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org At init time, KVM does compatibility checks to ensure that all online CPUs support hardware virtualization and a common set of features. But KVM uses hotplugged CPUs without such compatibility checks. On Intel CPUs, this leads to #GP if the hotplugged CPU doesn't support VMX or vmentry failure if the hotplugged CPU doesn't meet minimal feature requirements. Do compatibility checks when onlining a CPU and abort the online process if the hotplugged CPU is incompatible with online CPUs. CPU hotplug is disabled during hardware_enable_all() to prevent the corner case as shown below. A hotplugged CPU marks itself online in cpu_online_mask (1) and enables interrupt (2) before invoking callbacks registered in ONLINE section (3). So, if hardware_enable_all() is invoked on another CPU right after (2), then on_each_cpu() in hardware_enable_all() invokes hardware_enable_nolock() on the hotplugged CPU before kvm_online_cpu() is called. This makes the CPU escape from compatibility checks, which is risky. start_secondary { ... set_cpu_online(smp_processor_id(), true); <- 1 ... local_irq_enable(); <- 2 ... cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); <- 3 } Keep compatibility checks at KVM init time. It can help to find incompatibility issues earlier and refuse to load arch KVM module (e.g., kvm-intel). Loosen the WARN_ON in kvm_arch_check_processor_compat so that it can be invoked from KVM's CPU hotplug callback (i.e., kvm_online_cpu). Opportunistically, add a pr_err() for setup_vmcs_config() path in vmx_check_processor_compatibility() so that each possible error path has its own error message. Convert printk(KERN_ERR ... to pr_err to please checkpatch.pl Signed-off-by: Chao Gao Reviewed-by: Sean Christopherson --- arch/x86/kvm/vmx/vmx.c | 10 ++++++---- arch/x86/kvm/x86.c | 11 +++++++++-- virt/kvm/kvm_main.c | 18 +++++++++++++++++- 3 files changed, 32 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index fc94d7139f69..efde9faca02a 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -7120,20 +7120,22 @@ static int vmx_check_processor_compatibility(void) { struct vmcs_config vmcs_conf; struct vmx_capability vmx_cap; + int cpu = smp_processor_id(); if (!this_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) || !this_cpu_has(X86_FEATURE_VMX)) { - pr_err("kvm: VMX is disabled on CPU %d\n", smp_processor_id()); + pr_err("kvm: VMX is disabled on CPU %d\n", cpu); return -EIO; } - if (setup_vmcs_config(&vmcs_conf, &vmx_cap) < 0) + if (setup_vmcs_config(&vmcs_conf, &vmx_cap) < 0) { + pr_err("kvm: failed to setup vmcs config on CPU %d\n", cpu); return -EIO; + } if (nested) nested_vmx_setup_ctls_msrs(&vmcs_conf.nested, vmx_cap.ept); if (memcmp(&vmcs_config, &vmcs_conf, sizeof(struct vmcs_config)) != 0) { - printk(KERN_ERR "kvm: CPU %d feature inconsistency!\n", - smp_processor_id()); + pr_err("kvm: CPU %d feature inconsistency!\n", cpu); return -EIO; } return 0; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index e9777ffc50c2..219df62115d2 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -11550,9 +11550,16 @@ void kvm_arch_hardware_unsetup(void) int kvm_arch_check_processor_compat(void) { - struct cpuinfo_x86 *c = &cpu_data(smp_processor_id()); + int cpu = smp_processor_id(); + struct cpuinfo_x86 *c = &cpu_data(cpu); - WARN_ON(!irqs_disabled()); + /* + * Compatibility checks are done when loading KVM or in KVM's CPU + * hotplug callback. It ensures all online CPUs are compatible to run + * vCPUs. For other cases, compatibility checks are unnecessary or + * even problematic. Try to detect improper usages here. + */ + WARN_ON(!irqs_disabled() && cpu_active(cpu)); if (__cr4_reserved_bits(cpu_has, c) != __cr4_reserved_bits(cpu_has, &boot_cpu_data)) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index f60724736cb1..96df789ecd4d 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -4855,7 +4855,11 @@ static void hardware_enable_nolock(void *caller_name) static int kvm_online_cpu(unsigned int cpu) { - int ret = 0; + int ret; + + ret = kvm_arch_check_processor_compat(); + if (ret) + return ret; raw_spin_lock(&kvm_count_lock); /* @@ -4915,6 +4919,17 @@ static int hardware_enable_all(void) { int r = 0; + /* + * During onlining a CPU, cpu_online_mask is set before kvm_online_cpu() + * is called. on_each_cpu() between them includes the CPU. As a result, + * hardware_enable_nolock() may get invoked before kvm_online_cpu(). + * This would enable hardware virtualization on that cpu without + * compatibility checks, which can potentially crash system or break + * running VMs. + * + * Disable CPU hotplug to prevent this case from happening. + */ + cpus_read_lock(); raw_spin_lock(&kvm_count_lock); kvm_usage_count++; @@ -4929,6 +4944,7 @@ static int hardware_enable_all(void) } raw_spin_unlock(&kvm_count_lock); + cpus_read_unlock(); return r; }