From patchwork Wed Nov 30 23:09:33 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 13060703 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 96B60C4321E for ; Wed, 30 Nov 2022 23:25:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:Reply-To:List-Subscribe:List-Help: List-Post:List-Archive:List-Unsubscribe:List-Id:Cc:To:From:Subject:Message-ID :References:Mime-Version:In-Reply-To:Date:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=yxbBt+q0nat/mGz/J60XPfMWwXRNODZaJkN3NZCeQ+A=; b=ePf6lB/CCeXZqW W8yZvyaw5TMDP9Z0gw8iivj/vVRN5xfb7lsMAyMzee/VNHfDk2uVjONhxtMf5uALi0jPu9LnCD1py XGKHWEka0yv0RHDjG4N5gIMSgNu4v5reFov7lWozzQEhUBQX2fLXwPVl8p6toNiSLyqGkebhre+OT /Je41jw/doZA0lmCO5gSOn1qFoKGPvbxjQPCszb7O378mLGcG4r4A5eeNgffXVXZII1B8xHRbjSF8 CH8qk3GTuSwieNVytAv4pjMMWOP2dRmdVj00yxZVFnx7ftqYl6HfD87vSjq0u6Zo0NYL+ZI/dy8qP aGi2pQopfbjBZ7Rcn2Lw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1p0WSV-003DGG-Qq; Wed, 30 Nov 2022 23:25:43 +0000 Received: from mail-pf1-x44a.google.com ([2607:f8b0:4864:20::44a]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1p0WJu-0039ci-5S for linux-riscv@lists.infradead.org; Wed, 30 Nov 2022 23:16:52 +0000 Received: by mail-pf1-x44a.google.com with SMTP id f19-20020a056a001ad300b0056dd07cebfcso217940pfv.3 for ; Wed, 30 Nov 2022 15:16:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=6morZmBBP0CV2BvCfkeiOQYAEytvQNjuspBMIyc2id0=; b=sWQzejDxj89fP/6h20g08xJE4rIjODMnosC3GmCSUfi+aSeNDHNKftXKhh8nYT3l2D 0YK4iSHo8A04ByrB9qf3ZTd0XUbiMRcMFGBiIM/mHqplDmmEfAjOk9uIC81j45nqClMy v2jwYosdvWDLVw0MCV9UfthiEkgsqhc9Bc9tz5Enb/CFlxInO603HpDl//Lik3bmkg1m bBZtpxEk9GCvMmsM3ZPE+UjVHdMMXjkLtGTIGBqyljnfD/K4nvullx146+dygbRTS/Bh KJn5a954k2T5IJlWupgrvVwtXJhy4B7Pc5j+rX2xLePCLmpO6bBgk7atqvBnF48/gjyK Oz9w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=6morZmBBP0CV2BvCfkeiOQYAEytvQNjuspBMIyc2id0=; b=UFVvFj1+8j/X187E/vEI6C3pfrL0VfokxVwW1fXF+5x4BVDPHmIF+sgf9NClTJOTsy jXm0E+JEMUCTm8zVmFqKjmLPaIobBYgYy3ViWNROqnNSnOtq41cYFnBJXfMItqzzM/Fi JQPGkw0DEcBsZvTTCCJPkHTgkta6zljRUMlfOiIkzROA5kp06oomdN+9n838CZC8gJEX ZvDrh13IDx/iFdYdVvPAPyW9inUlMy5aH8z/QFid10B1RKEMZnj2ArsZJm4UbpF7sKt2 fov1Px/uuShCeqXa5tgvPcu0cJJgAt982AnfKUdDXNVy+yA+GDQX58j+dJ21OSSa5Dub eN+Q== X-Gm-Message-State: ANoB5ploEqv10S1CWT/+rDMvDUrVmd8okzyvdTCeKv+Rx+DdiigEcHyw XLaw971ptuUFIrhyh6OLi/S2u9awyMo= X-Google-Smtp-Source: AA0mqf4+0TRXr+cnrk+BZdgZcvjM1FWymvWLiwE/quV2nt1zGgBs/MDCausMUoavyu2bOWxbpEos7xdiJdA= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a17:902:b48f:b0:189:8b6:95f6 with SMTP id y15-20020a170902b48f00b0018908b695f6mr44843975plr.71.1669849862778; Wed, 30 Nov 2022 15:11:02 -0800 (PST) Date: Wed, 30 Nov 2022 23:09:33 +0000 In-Reply-To: <20221130230934.1014142-1-seanjc@google.com> Mime-Version: 1.0 References: <20221130230934.1014142-1-seanjc@google.com> X-Mailer: git-send-email 2.38.1.584.g0f3c55d4c2-goog Message-ID: <20221130230934.1014142-50-seanjc@google.com> Subject: [PATCH v2 49/50] KVM: Opt out of generic hardware enabling on s390 and PPC From: Sean Christopherson To: Paolo Bonzini , Marc Zyngier , Huacai Chen , Aleksandar Markovic , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , Matthew Rosato , Eric Farman , Sean Christopherson , Vitaly Kuznetsov , David Woodhouse , Paul Durrant Cc: James Morse , Alexandru Elisei , Suzuki K Poulose , Oliver Upton , Atish Patra , David Hildenbrand , kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, kvmarm@lists.cs.columbia.edu, 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, linux-kernel@vger.kernel.org, Yuan Yao , Cornelia Huck , Isaku Yamahata , " =?utf-8?q?Philippe_Mathieu-Da?= =?utf-8?q?ud=C3=A9?= " , Fabiano Rosas , Michael Ellerman , Kai Huang , Chao Gao , Thomas Gleixner X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221130_151650_277208_35B14CE4 X-CRM114-Status: GOOD ( 17.62 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Sean Christopherson Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Allow architectures to opt out of the generic hardware enabling logic, and opt out on both s390 and PPC, which don't need to manually enable virtualization as it's always on (when available). In addition to letting s390 and PPC drop a bit of dead code, this will hopefully also allow ARM to clean up its related code, e.g. ARM has its own per-CPU flag to track which CPUs have enable hardware due to the need to keep hardware enabled indefinitely when pKVM is enabled. Signed-off-by: Sean Christopherson Acked-by: Anup Patel --- arch/arm64/kvm/Kconfig | 1 + arch/mips/kvm/Kconfig | 1 + arch/powerpc/include/asm/kvm_host.h | 1 - arch/powerpc/kvm/powerpc.c | 5 ----- arch/riscv/kvm/Kconfig | 1 + arch/s390/include/asm/kvm_host.h | 1 - arch/s390/kvm/kvm-s390.c | 6 ------ arch/x86/kvm/Kconfig | 1 + include/linux/kvm_host.h | 4 ++++ virt/kvm/Kconfig | 3 +++ virt/kvm/kvm_main.c | 30 +++++++++++++++++++++++------ 11 files changed, 35 insertions(+), 19 deletions(-) diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig index 815cc118c675..0a7d2116b27b 100644 --- a/arch/arm64/kvm/Kconfig +++ b/arch/arm64/kvm/Kconfig @@ -21,6 +21,7 @@ if VIRTUALIZATION menuconfig KVM bool "Kernel-based Virtual Machine (KVM) support" depends on HAVE_KVM + select KVM_GENERIC_HARDWARE_ENABLING select MMU_NOTIFIER select PREEMPT_NOTIFIERS select HAVE_KVM_CPU_RELAX_INTERCEPT diff --git a/arch/mips/kvm/Kconfig b/arch/mips/kvm/Kconfig index 91d197bee9c0..29e51649203b 100644 --- a/arch/mips/kvm/Kconfig +++ b/arch/mips/kvm/Kconfig @@ -28,6 +28,7 @@ config KVM select MMU_NOTIFIER select SRCU select INTERVAL_TREE + select KVM_GENERIC_HARDWARE_ENABLING help Support for hosting Guest kernels. diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 0a80e80c7b9e..959f566a455c 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -876,7 +876,6 @@ struct kvm_vcpu_arch { #define __KVM_HAVE_ARCH_WQP #define __KVM_HAVE_CREATE_DEVICE -static inline void kvm_arch_hardware_disable(void) {} static inline void kvm_arch_sync_events(struct kvm *kvm) {} static inline void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) {} static inline void kvm_arch_flush_shadow_all(struct kvm *kvm) {} diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index f5b4ff6bfc89..4c5405fc5538 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -435,11 +435,6 @@ int kvmppc_ld(struct kvm_vcpu *vcpu, ulong *eaddr, int size, void *ptr, } EXPORT_SYMBOL_GPL(kvmppc_ld); -int kvm_arch_hardware_enable(void) -{ - return 0; -} - int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) { struct kvmppc_ops *kvm_ops = NULL; diff --git a/arch/riscv/kvm/Kconfig b/arch/riscv/kvm/Kconfig index f36a737d5f96..d5a658a047a7 100644 --- a/arch/riscv/kvm/Kconfig +++ b/arch/riscv/kvm/Kconfig @@ -20,6 +20,7 @@ if VIRTUALIZATION config KVM tristate "Kernel-based Virtual Machine (KVM) support (EXPERIMENTAL)" depends on RISCV_SBI && MMU + select KVM_GENERIC_HARDWARE_ENABLING select MMU_NOTIFIER select PREEMPT_NOTIFIERS select KVM_MMIO diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h index d67ce719d16a..2bbc3d54959d 100644 --- a/arch/s390/include/asm/kvm_host.h +++ b/arch/s390/include/asm/kvm_host.h @@ -1031,7 +1031,6 @@ extern char sie_exit; extern int kvm_s390_gisc_register(struct kvm *kvm, u32 gisc); extern int kvm_s390_gisc_unregister(struct kvm *kvm, u32 gisc); -static inline void kvm_arch_hardware_disable(void) {} static inline void kvm_arch_sync_events(struct kvm *kvm) {} static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {} static inline void kvm_arch_free_memslot(struct kvm *kvm, diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 7ad8252e92c2..bd25076aa19b 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -256,12 +256,6 @@ debug_info_t *kvm_s390_dbf; debug_info_t *kvm_s390_dbf_uv; /* Section: not file related */ -int kvm_arch_hardware_enable(void) -{ - /* every s390 is virtualization enabled ;-) */ - return 0; -} - /* forward declarations */ static void kvm_gmap_notifier(struct gmap *gmap, unsigned long start, unsigned long end); diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig index fbeaa9ddef59..8e578311ca9d 100644 --- a/arch/x86/kvm/Kconfig +++ b/arch/x86/kvm/Kconfig @@ -49,6 +49,7 @@ config KVM select SRCU select INTERVAL_TREE select HAVE_KVM_PM_NOTIFIER if PM + select KVM_GENERIC_HARDWARE_ENABLING help Support hosting fully virtualized guest machines using hardware virtualization extensions. You will need a fairly recent diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 616e8e90558b..ffb4f9c3371f 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1457,8 +1457,10 @@ void kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu, struct dentry *debugfs_ static inline void kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu) {} #endif +#ifdef CONFIG_KVM_GENERIC_HARDWARE_ENABLING int kvm_arch_hardware_enable(void); void kvm_arch_hardware_disable(void); +#endif 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); @@ -2090,7 +2092,9 @@ static inline bool kvm_check_request(int req, struct kvm_vcpu *vcpu) } } +#ifdef CONFIG_KVM_GENERIC_HARDWARE_ENABLING extern bool kvm_rebooting; +#endif extern unsigned int halt_poll_ns; extern unsigned int halt_poll_ns_grow; diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig index 800f9470e36b..d28df77345e1 100644 --- a/virt/kvm/Kconfig +++ b/virt/kvm/Kconfig @@ -86,3 +86,6 @@ config KVM_XFER_TO_GUEST_WORK config HAVE_KVM_PM_NOTIFIER bool + +config KVM_GENERIC_HARDWARE_ENABLING + bool diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index c12db3839114..6a2be96557c2 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -102,9 +102,6 @@ EXPORT_SYMBOL_GPL(halt_poll_ns_shrink); DEFINE_MUTEX(kvm_lock); LIST_HEAD(vm_list); -static DEFINE_PER_CPU(bool, hardware_enabled); -static int kvm_usage_count; - static struct kmem_cache *kvm_vcpu_cache; static __read_mostly struct preempt_ops kvm_preempt_ops; @@ -146,9 +143,6 @@ static void hardware_disable_all(void); static void kvm_io_bus_destroy(struct kvm_io_bus *bus); -__visible bool kvm_rebooting; -EXPORT_SYMBOL_GPL(kvm_rebooting); - #define KVM_EVENT_CREATE_VM 0 #define KVM_EVENT_DESTROY_VM 1 static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm); @@ -5024,6 +5018,13 @@ static struct miscdevice kvm_dev = { &kvm_chardev_ops, }; +#ifdef CONFIG_KVM_GENERIC_HARDWARE_ENABLING +__visible bool kvm_rebooting; +EXPORT_SYMBOL_GPL(kvm_rebooting); + +static DEFINE_PER_CPU(bool, hardware_enabled); +static int kvm_usage_count; + static int __hardware_enable_nolock(void) { if (__this_cpu_read(hardware_enabled)) @@ -5185,6 +5186,17 @@ static struct syscore_ops kvm_syscore_ops = { .suspend = kvm_suspend, .resume = kvm_resume, }; +#else /* CONFIG_KVM_GENERIC_HARDWARE_ENABLING */ +static int hardware_enable_all(void) +{ + return 0; +} + +static void hardware_disable_all(void) +{ + +} +#endif /* CONFIG_KVM_GENERIC_HARDWARE_ENABLING */ static void kvm_io_bus_destroy(struct kvm_io_bus *bus) { @@ -5873,6 +5885,7 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align, struct module *module) int r; int cpu; +#ifdef CONFIG_KVM_GENERIC_HARDWARE_ENABLING r = cpuhp_setup_state_nocalls(CPUHP_AP_KVM_ONLINE, "kvm/cpu:online", kvm_online_cpu, kvm_offline_cpu); if (r) @@ -5880,6 +5893,7 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align, struct module *module) register_reboot_notifier(&kvm_reboot_notifier); register_syscore_ops(&kvm_syscore_ops); +#endif /* A kmem cache lets us meet the alignment requirements of fx_save. */ if (!vcpu_align) @@ -5947,9 +5961,11 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align, struct module *module) free_cpumask_var(per_cpu(cpu_kick_mask, cpu)); kmem_cache_destroy(kvm_vcpu_cache); out_free_3: +#ifdef CONFIG_KVM_GENERIC_HARDWARE_ENABLING unregister_syscore_ops(&kvm_syscore_ops); unregister_reboot_notifier(&kvm_reboot_notifier); cpuhp_remove_state_nocalls(CPUHP_AP_KVM_ONLINE); +#endif return r; } EXPORT_SYMBOL_GPL(kvm_init); @@ -5971,9 +5987,11 @@ void kvm_exit(void) kmem_cache_destroy(kvm_vcpu_cache); kvm_vfio_ops_exit(); kvm_async_pf_deinit(); +#ifdef CONFIG_KVM_GENERIC_HARDWARE_ENABLING unregister_syscore_ops(&kvm_syscore_ops); unregister_reboot_notifier(&kvm_reboot_notifier); cpuhp_remove_state_nocalls(CPUHP_AP_KVM_ONLINE); +#endif kvm_irqfd_exit(); } EXPORT_SYMBOL_GPL(kvm_exit);