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From: Sean Christopherson <seanjc@google.com>
To: Paolo Bonzini <pbonzini@redhat.com>,
	Marc Zyngier <maz@kernel.org>,
	 Huacai Chen <chenhuacai@kernel.org>,
	 Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>,
	Anup Patel <anup@brainfault.org>,
	 Paul Walmsley <paul.walmsley@sifive.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	 Albert Ou <aou@eecs.berkeley.edu>,
	Christian Borntraeger <borntraeger@linux.ibm.com>,
	 Janosch Frank <frankja@linux.ibm.com>,
	Claudio Imbrenda <imbrenda@linux.ibm.com>,
	 Matthew Rosato <mjrosato@linux.ibm.com>,
	Eric Farman <farman@linux.ibm.com>,
	 Sean Christopherson <seanjc@google.com>,
	Vitaly Kuznetsov <vkuznets@redhat.com>,
	 David Woodhouse <dwmw2@infradead.org>,
	Paul Durrant <paul@xen.org>
Cc: kvm@vger.kernel.org, "David Hildenbrand" <david@redhat.com>,
	"Atish Patra" <atishp@atishpatra.org>,
	linux-kernel@vger.kernel.org, "Kai Huang" <kai.huang@intel.com>,
	linux-riscv@lists.infradead.org, kvmarm@lists.cs.columbia.edu,
	linux-s390@vger.kernel.org, "Chao Gao" <chao.gao@intel.com>,
	"Suzuki K Poulose" <suzuki.poulose@arm.com>,
	"Yuan Yao" <yuan.yao@intel.com>,
	kvmarm@lists.linux.dev, "Thomas Gleixner" <tglx@linutronix.de>,
	"Alexandru Elisei" <alexandru.elisei@arm.com>,
	linux-arm-kernel@lists.infradead.org,
	"Isaku Yamahata" <isaku.yamahata@intel.com>,
	"Philippe Mathieu-Daudé" <philmd@linaro.org>,
	"Fabiano Rosas" <farosas@linux.ibm.com>,
	"Cornelia Huck" <cohuck@redhat.com>,
	linux-mips@vger.kernel.org,
	"Oliver Upton" <oliver.upton@linux.dev>,
	"James Morse" <james.morse@arm.com>,
	kvm-riscv@lists.infradead.org, linuxppc-dev@lists.ozlabs.org
Subject: [PATCH v2 09/50] KVM: Drop arch hardware (un)setup hooks
Date: Wed, 30 Nov 2022 23:08:53 +0000	[thread overview]
Message-ID: <20221130230934.1014142-10-seanjc@google.com> (raw)
In-Reply-To: <20221130230934.1014142-1-seanjc@google.com>

Drop kvm_arch_hardware_setup() and kvm_arch_hardware_unsetup() now that
all implementations are nops.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>	# s390
Acked-by: Anup Patel <anup@brainfault.org>
---
 arch/arm64/include/asm/kvm_host.h   |  1 -
 arch/arm64/kvm/arm.c                |  5 -----
 arch/mips/include/asm/kvm_host.h    |  1 -
 arch/mips/kvm/mips.c                |  5 -----
 arch/powerpc/include/asm/kvm_host.h |  1 -
 arch/powerpc/kvm/powerpc.c          |  5 -----
 arch/riscv/include/asm/kvm_host.h   |  1 -
 arch/riscv/kvm/main.c               |  5 -----
 arch/s390/kvm/kvm-s390.c            | 10 ----------
 arch/x86/kvm/x86.c                  | 10 ----------
 include/linux/kvm_host.h            |  2 --
 virt/kvm/kvm_main.c                 |  7 -------
 12 files changed, 53 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 45e2136322ba..5d5a887e63a5 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -859,7 +859,6 @@ static inline bool kvm_system_needs_idmapped_vectors(void)
 
 void kvm_arm_vcpu_ptrauth_trap(struct kvm_vcpu *vcpu);
 
-static inline void kvm_arch_hardware_unsetup(void) {}
 static inline void kvm_arch_sync_events(struct kvm *kvm) {}
 static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
 
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 7b107fa540fa..c6732ac329ca 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -63,11 +63,6 @@ int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
 	return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
 }
 
-int kvm_arch_hardware_setup(void *opaque)
-{
-	return 0;
-}
-
 int kvm_arch_check_processor_compat(void *opaque)
 {
 	return 0;
diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h
index 5cedb28e8a40..28f0ba97db71 100644
--- a/arch/mips/include/asm/kvm_host.h
+++ b/arch/mips/include/asm/kvm_host.h
@@ -888,7 +888,6 @@ extern unsigned long kvm_mips_get_ramsize(struct kvm *kvm);
 extern int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
 			     struct kvm_mips_interrupt *irq);
 
-static inline void kvm_arch_hardware_unsetup(void) {}
 static inline void kvm_arch_sync_events(struct kvm *kvm) {}
 static inline void kvm_arch_free_memslot(struct kvm *kvm,
 					 struct kvm_memory_slot *slot) {}
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index a25e0b73ee70..af29490d9740 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -135,11 +135,6 @@ void kvm_arch_hardware_disable(void)
 	kvm_mips_callbacks->hardware_disable();
 }
 
-int kvm_arch_hardware_setup(void *opaque)
-{
-	return 0;
-}
-
 int kvm_arch_check_processor_compat(void *opaque)
 {
 	return 0;
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index caea15dcb91d..5d2c3a487e73 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -877,7 +877,6 @@ struct kvm_vcpu_arch {
 #define __KVM_HAVE_CREATE_DEVICE
 
 static inline void kvm_arch_hardware_disable(void) {}
-static inline void kvm_arch_hardware_unsetup(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 04494a4fb37a..5faf69421f13 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -440,11 +440,6 @@ int kvm_arch_hardware_enable(void)
 	return 0;
 }
 
-int kvm_arch_hardware_setup(void *opaque)
-{
-	return 0;
-}
-
 int kvm_arch_check_processor_compat(void *opaque)
 {
 	return kvmppc_core_check_processor_compat();
diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h
index dbbf43d52623..8c771fc4f5d2 100644
--- a/arch/riscv/include/asm/kvm_host.h
+++ b/arch/riscv/include/asm/kvm_host.h
@@ -229,7 +229,6 @@ struct kvm_vcpu_arch {
 	bool pause;
 };
 
-static inline void kvm_arch_hardware_unsetup(void) {}
 static inline void kvm_arch_sync_events(struct kvm *kvm) {}
 static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
 
diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c
index df2d8716851f..a146fa0ce4d2 100644
--- a/arch/riscv/kvm/main.c
+++ b/arch/riscv/kvm/main.c
@@ -25,11 +25,6 @@ int kvm_arch_check_processor_compat(void *opaque)
 	return 0;
 }
 
-int kvm_arch_hardware_setup(void *opaque)
-{
-	return 0;
-}
-
 int kvm_arch_hardware_enable(void)
 {
 	unsigned long hideleg, hedeleg;
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 97c7ccd189eb..829e6e046003 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -329,16 +329,6 @@ static struct notifier_block kvm_clock_notifier = {
 	.notifier_call = kvm_clock_sync,
 };
 
-int kvm_arch_hardware_setup(void *opaque)
-{
-	return 0;
-}
-
-void kvm_arch_hardware_unsetup(void)
-{
-
-}
-
 static void allow_cpu_feat(unsigned long nr)
 {
 	set_bit_inv(nr, kvm_s390_available_cpu_feat);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index fe5f2e49b5eb..915d57c3b41d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -12020,16 +12020,6 @@ void kvm_arch_hardware_disable(void)
 	drop_user_return_notifiers();
 }
 
-int kvm_arch_hardware_setup(void *opaque)
-{
-	return 0;
-}
-
-void kvm_arch_hardware_unsetup(void)
-{
-
-}
-
 int kvm_arch_check_processor_compat(void *opaque)
 {
 	struct cpuinfo_x86 *c = &cpu_data(smp_processor_id());
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 8f874a964313..f2e0e78d2d92 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1463,8 +1463,6 @@ static inline void kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu) {}
 
 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_vcpu_runnable(struct kvm_vcpu *vcpu);
 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 988f7d92db2e..0e62887e8ce1 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -5862,10 +5862,6 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
 	if (r)
 		return r;
 
-	r = kvm_arch_hardware_setup(opaque);
-	if (r < 0)
-		goto err_hw_setup;
-
 	if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
 		r = -ENOMEM;
 		goto err_hw_enabled;
@@ -5958,8 +5954,6 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
 out_free_2:
 	free_cpumask_var(cpus_hardware_enabled);
 err_hw_enabled:
-	kvm_arch_hardware_unsetup();
-err_hw_setup:
 	kvm_arch_exit();
 	return r;
 }
@@ -5988,7 +5982,6 @@ void kvm_exit(void)
 	on_each_cpu(hardware_disable_nolock, NULL, 1);
 	kvm_irqfd_exit();
 	free_cpumask_var(cpus_hardware_enabled);
-	kvm_arch_hardware_unsetup();
 	kvm_arch_exit();
 }
 EXPORT_SYMBOL_GPL(kvm_exit);
-- 
2.38.1.584.g0f3c55d4c2-goog


  parent reply	other threads:[~2022-11-30 23:18 UTC|newest]

Thread overview: 77+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-11-30 23:08 [PATCH v2 00/50] KVM: Rework kvm_init() and hardware enabling Sean Christopherson
2022-11-30 23:08 ` [PATCH v2 01/50] KVM: Register /dev/kvm as the _very_ last thing during initialization Sean Christopherson
2022-11-30 23:08 ` [PATCH v2 02/50] KVM: Initialize IRQ FD after arch hardware setup Sean Christopherson
2022-11-30 23:08 ` [PATCH v2 03/50] KVM: Allocate cpus_hardware_enabled " Sean Christopherson
2022-11-30 23:08 ` [PATCH v2 04/50] KVM: Teardown VFIO ops earlier in kvm_exit() Sean Christopherson
2022-11-30 23:08 ` [PATCH v2 05/50] KVM: s390: Unwind kvm_arch_init() piece-by-piece() if a step fails Sean Christopherson
2022-11-30 23:08 ` [PATCH v2 06/50] KVM: s390: Move hardware setup/unsetup to init/exit Sean Christopherson
2022-11-30 23:08 ` [PATCH v2 07/50] KVM: x86: Do timer initialization after XCR0 configuration Sean Christopherson
2022-11-30 23:08 ` [PATCH v2 08/50] KVM: x86: Move hardware setup/unsetup to init/exit Sean Christopherson
2022-11-30 23:08 ` Sean Christopherson [this message]
2022-11-30 23:08 ` [PATCH v2 10/50] KVM: VMX: Reset eVMCS controls in VP assist page during hardware disabling Sean Christopherson
2022-12-01 15:42   ` Vitaly Kuznetsov
2022-11-30 23:08 ` [PATCH v2 11/50] KVM: VMX: Don't bother disabling eVMCS static key on module exit Sean Christopherson
2022-11-30 23:08 ` [PATCH v2 12/50] KVM: VMX: Move Hyper-V eVMCS initialization to helper Sean Christopherson
2022-12-01 15:22   ` Vitaly Kuznetsov
2022-11-30 23:08 ` [PATCH v2 13/50] KVM: x86: Move guts of kvm_arch_init() to standalone helper Sean Christopherson
2022-11-30 23:08 ` [PATCH v2 14/50] KVM: VMX: Do _all_ initialization before exposing /dev/kvm to userspace Sean Christopherson
2022-11-30 23:08 ` [PATCH v2 15/50] KVM: x86: Serialize vendor module initialization (hardware setup) Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 16/50] KVM: arm64: Simplify the CPUHP logic Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 17/50] KVM: arm64: Free hypervisor allocations if vector slot init fails Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 18/50] KVM: arm64: Unregister perf callbacks if hypervisor finalization fails Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 19/50] KVM: arm64: Do arm/arch initialization without bouncing through kvm_init() Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 20/50] KVM: arm64: Mark kvm_arm_init() and its unique descendants as __init Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 21/50] KVM: MIPS: Hardcode callbacks to hardware virtualization extensions Sean Christopherson
2022-12-01 22:00   ` Philippe Mathieu-Daudé
2022-12-01 22:49     ` Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 22/50] KVM: MIPS: Setup VZ emulation? directly from kvm_mips_init() Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 23/50] KVM: MIPS: Register die notifier prior to kvm_init() Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 24/50] KVM: RISC-V: Do arch init directly in riscv_kvm_init() Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 25/50] KVM: RISC-V: Tag init functions and data with __init, __ro_after_init Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 26/50] KVM: PPC: Move processor compatibility check to module init Sean Christopherson
2022-12-01  5:21   ` Michael Ellerman
2022-12-01 16:38     ` Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 27/50] KVM: s390: Do s390 specific init without bouncing through kvm_init() Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 28/50] KVM: s390: Mark __kvm_s390_init() and its descendants as __init Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 29/50] KVM: Drop kvm_arch_{init,exit}() hooks Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 30/50] KVM: VMX: Make VMCS configuration/capabilities structs read-only after init Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 31/50] KVM: x86: Do CPU compatibility checks in x86 code Sean Christopherson
2022-12-02 12:16   ` Huang, Kai
2022-12-05 20:52   ` Isaku Yamahata
2022-12-05 21:12     ` Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 32/50] KVM: Drop kvm_arch_check_processor_compat() hook Sean Christopherson
2022-12-02 12:18   ` Huang, Kai
2022-11-30 23:09 ` [PATCH v2 33/50] KVM: x86: Use KBUILD_MODNAME to specify vendor module name Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 34/50] KVM: x86: Unify pr_fmt to use module name for all KVM modules Sean Christopherson
2022-12-01 10:43   ` Paul Durrant
2022-11-30 23:09 ` [PATCH v2 35/50] KVM: VMX: Use current CPU's info to perform "disabled by BIOS?" checks Sean Christopherson
2022-12-02 12:18   ` Huang, Kai
2022-11-30 23:09 ` [PATCH v2 36/50] KVM: x86: Do VMX/SVM support checks directly in vendor code Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 37/50] KVM: VMX: Shuffle support checks and hardware enabling code around Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 38/50] KVM: SVM: Check for SVM support in CPU compatibility checks Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 39/50] KVM: x86: Move CPU compat checks hook to kvm_x86_ops (from kvm_x86_init_ops) Sean Christopherson
2022-12-02 13:01   ` Huang, Kai
2022-12-05 21:04   ` Isaku Yamahata
2022-11-30 23:09 ` [PATCH v2 40/50] KVM: x86: Do compatibility checks when onlining CPU Sean Christopherson
2022-12-02 13:03   ` Huang, Kai
2022-12-02 13:36   ` Huang, Kai
2022-12-02 16:04     ` Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 41/50] KVM: Rename and move CPUHP_AP_KVM_STARTING to ONLINE section Sean Christopherson
2022-12-02 13:06   ` Huang, Kai
2022-12-02 16:08     ` Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 42/50] KVM: Disable CPU hotplug during hardware enabling/disabling Sean Christopherson
2022-12-02 12:59   ` Huang, Kai
2022-12-02 16:31     ` Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 43/50] KVM: Ensure CPU is stable during low level hardware enable/disable Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 44/50] KVM: Drop kvm_count_lock and instead protect kvm_usage_count with kvm_lock Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 45/50] KVM: Remove on_each_cpu(hardware_disable_nolock) in kvm_exit() Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 46/50] KVM: Use a per-CPU variable to track which CPUs have enabled virtualization Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 47/50] KVM: Make hardware_enable_failed a local variable in the "enable all" path Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 48/50] KVM: Register syscore (suspend/resume) ops early in kvm_init() Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 49/50] KVM: Opt out of generic hardware enabling on s390 and PPC Sean Christopherson
2022-11-30 23:09 ` [PATCH v2 50/50] KVM: Clean up error labels in kvm_init() Sean Christopherson
2022-12-02  8:02 ` [PATCH v2 00/50] KVM: Rework kvm_init() and hardware enabling Chao Gao
2022-12-27 13:02 ` Paolo Bonzini
2022-12-28 11:22   ` Marc Zyngier
2022-12-28 11:58     ` Paolo Bonzini
2022-12-29 20:52     ` Paolo Bonzini

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