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(localhost [IPv6:::1]) by ozlabs.ru (Postfix) with ESMTP id 07ECBAE80212; Fri, 3 Sep 2021 01:22:59 -0400 (EDT) From: Alexey Kardashevskiy To: linuxppc-dev@lists.ozlabs.org Cc: Alexey Kardashevskiy , kvm@vger.kernel.org, kvm-ppc@vger.kernel.org, Paolo Bonzini , Michael Ellerman , Fabiano Rosas Subject: [PATCH kernel] KVM: PPC: Book3S: Merge powerpc's debugfs entry content into generic entry Date: Fri, 3 Sep 2021 15:22:57 +1000 Message-Id: <20210903052257.2348036-1-aik@ozlabs.ru> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org At the moment the generic KVM code creates an "%pid-%fd" entry per a KVM instance; and the PPC HV KVM creates its own at "vm%pid". The rproblems with the PPC entries are: 1. they do not allow multiple VMs in the same process (which is extremely rare case mostly used by syzkaller fuzzer); 2. prone to race bugs like the generic KVM code had fixed in commit 85cd39af14f4 ("KVM: Do not leak memory for duplicate debugfs directories"). This defines kvm_arch_create_kvm_debugfs() similar to one for vcpus. This defines 2 hooks in kvmppc_ops for allowing specific KVM implementations to add necessary entries. This makes use of already existing kvm_arch_create_vcpu_debugfs. This removes no more used debugfs_dir pointers from PPC kvm_arch structs. Suggested-by: Fabiano Rosas Signed-off-by: Alexey Kardashevskiy --- arch/powerpc/include/asm/kvm_host.h | 6 +++--- arch/powerpc/include/asm/kvm_ppc.h | 2 ++ include/linux/kvm_host.h | 3 +++ arch/powerpc/kvm/book3s_64_mmu_hv.c | 2 +- arch/powerpc/kvm/book3s_64_mmu_radix.c | 2 +- arch/powerpc/kvm/book3s_hv.c | 30 +++++++++----------------- arch/powerpc/kvm/powerpc.c | 12 +++++++++++ virt/kvm/kvm_main.c | 3 +++ 8 files changed, 35 insertions(+), 25 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 2bcac6da0a4b..e4f2feb67b53 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -296,7 +296,6 @@ struct kvm_arch { bool dawr1_enabled; pgd_t *pgtable; u64 process_table; - struct dentry *debugfs_dir; struct kvm_resize_hpt *resize_hpt; /* protected by kvm->lock */ #endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */ #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE @@ -828,8 +827,6 @@ struct kvm_vcpu_arch { struct kvmhv_tb_accumulator rm_exit; /* real-mode exit code */ struct kvmhv_tb_accumulator guest_time; /* guest execution */ struct kvmhv_tb_accumulator cede_time; /* time napping inside guest */ - - struct dentry *debugfs_dir; #endif /* CONFIG_KVM_BOOK3S_HV_EXIT_TIMING */ }; @@ -868,4 +865,7 @@ static inline void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) {} static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {} static inline void kvm_arch_vcpu_block_finish(struct kvm_vcpu *vcpu) {} +#define __KVM_HAVE_ARCH_VCPU_DEBUGFS +#define __KVM_HAVE_ARCH_KVM_DEBUGFS + #endif /* __POWERPC_KVM_HOST_H__ */ diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index 6355a6980ccf..8b3f7f6e3f12 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -316,6 +316,8 @@ struct kvmppc_ops { int (*svm_off)(struct kvm *kvm); int (*enable_dawr1)(struct kvm *kvm); bool (*hash_v3_possible)(void); + void (*create_kvm_debugfs)(struct kvm *kvm); + void (*create_vcpu_debugfs)(struct kvm_vcpu *vcpu, struct dentry *debugfs_dentry); }; extern struct kvmppc_ops *kvmppc_hv_ops; diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index ae7735b490b4..74d2c1c3df1b 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1021,6 +1021,9 @@ int kvm_arch_pm_notifier(struct kvm *kvm, unsigned long state); #ifdef __KVM_HAVE_ARCH_VCPU_DEBUGFS void kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu, struct dentry *debugfs_dentry); #endif +#ifdef __KVM_HAVE_ARCH_KVM_DEBUGFS +void kvm_arch_create_kvm_debugfs(struct kvm *kvm); +#endif int kvm_arch_hardware_enable(void); void kvm_arch_hardware_disable(void); diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index c63e263312a4..33dae253a0ac 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -2112,7 +2112,7 @@ static const struct file_operations debugfs_htab_fops = { void kvmppc_mmu_debugfs_init(struct kvm *kvm) { - debugfs_create_file("htab", 0400, kvm->arch.debugfs_dir, kvm, + debugfs_create_file("htab", 0400, kvm->debugfs_dentry, kvm, &debugfs_htab_fops); } diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c index c5508744e14c..f4e083c20872 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_radix.c +++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c @@ -1452,7 +1452,7 @@ static const struct file_operations debugfs_radix_fops = { void kvmhv_radix_debugfs_init(struct kvm *kvm) { - debugfs_create_file("radix", 0400, kvm->arch.debugfs_dir, kvm, + debugfs_create_file("radix", 0400, kvm->debugfs_dentry, kvm, &debugfs_radix_fops); } diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index c8f12b056968..325b388c725a 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -2771,19 +2771,14 @@ static const struct file_operations debugfs_timings_ops = { }; /* Create a debugfs directory for the vcpu */ -static void debugfs_vcpu_init(struct kvm_vcpu *vcpu, unsigned int id) +static void kvmppc_arch_create_vcpu_debugfs_hv(struct kvm_vcpu *vcpu, struct dentry *debugfs_dentry) { - char buf[16]; - struct kvm *kvm = vcpu->kvm; - - snprintf(buf, sizeof(buf), "vcpu%u", id); - vcpu->arch.debugfs_dir = debugfs_create_dir(buf, kvm->arch.debugfs_dir); - debugfs_create_file("timings", 0444, vcpu->arch.debugfs_dir, vcpu, + debugfs_create_file("timings", 0444, debugfs_dentry, vcpu, &debugfs_timings_ops); } #else /* CONFIG_KVM_BOOK3S_HV_EXIT_TIMING */ -static void debugfs_vcpu_init(struct kvm_vcpu *vcpu, unsigned int id) +static void kvmppc_arch_create_vcpu_debugfs_hv(struct kvm_vcpu *vcpu, struct dentry *debugfs_dentry) { } #endif /* CONFIG_KVM_BOOK3S_HV_EXIT_TIMING */ @@ -2907,8 +2902,6 @@ static int kvmppc_core_vcpu_create_hv(struct kvm_vcpu *vcpu) vcpu->arch.cpu_type = KVM_CPU_3S_64; kvmppc_sanity_check(vcpu); - debugfs_vcpu_init(vcpu, id); - return 0; } @@ -5186,7 +5179,6 @@ void kvmppc_free_host_rm_ops(void) static int kvmppc_core_init_vm_hv(struct kvm *kvm) { unsigned long lpcr, lpid; - char buf[32]; int ret; mutex_init(&kvm->arch.uvmem_lock); @@ -5319,16 +5311,14 @@ static int kvmppc_core_init_vm_hv(struct kvm *kvm) kvm->arch.smt_mode = 1; kvm->arch.emul_smt_mode = 1; - /* - * Create a debugfs directory for the VM - */ - snprintf(buf, sizeof(buf), "vm%d", current->pid); - kvm->arch.debugfs_dir = debugfs_create_dir(buf, kvm_debugfs_dir); + return 0; +} + +static void kvmppc_arch_create_kvm_debugfs_hv(struct kvm *kvm) +{ kvmppc_mmu_debugfs_init(kvm); if (radix_enabled()) kvmhv_radix_debugfs_init(kvm); - - return 0; } static void kvmppc_free_vcores(struct kvm *kvm) @@ -5342,8 +5332,6 @@ static void kvmppc_free_vcores(struct kvm *kvm) static void kvmppc_core_destroy_vm_hv(struct kvm *kvm) { - debugfs_remove_recursive(kvm->arch.debugfs_dir); - if (!cpu_has_feature(CPU_FTR_ARCH_300)) kvm_hv_vm_deactivated(); @@ -5996,6 +5984,8 @@ static struct kvmppc_ops kvm_ops_hv = { .svm_off = kvmhv_svm_off, .enable_dawr1 = kvmhv_enable_dawr1, .hash_v3_possible = kvmppc_hash_v3_possible, + .create_vcpu_debugfs = kvmppc_arch_create_vcpu_debugfs_hv, + .create_kvm_debugfs = kvmppc_arch_create_kvm_debugfs_hv, }; static int kvm_init_subcore_bitmap(void) diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index b4e6f70b97b9..9c18d599171b 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -2505,3 +2505,15 @@ int kvm_arch_init(void *opaque) } EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_ppc_instr); + +void kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu, struct dentry *debugfs_dentry) +{ + if (vcpu->kvm->arch.kvm_ops->create_vcpu_debugfs) + vcpu->kvm->arch.kvm_ops->create_vcpu_debugfs(vcpu, debugfs_dentry); +} + +void kvm_arch_create_kvm_debugfs(struct kvm *kvm) +{ + if (kvm->arch.kvm_ops->create_kvm_debugfs) + kvm->arch.kvm_ops->create_kvm_debugfs(kvm); +} diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index b50dbe269f4b..f9d423535f00 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -954,6 +954,9 @@ static int kvm_create_vm_debugfs(struct kvm *kvm, int fd) kvm->debugfs_dentry, stat_data, &stat_fops_per_vm); } +#ifdef __KVM_HAVE_ARCH_KVM_DEBUGFS + kvm_arch_create_kvm_debugfs(kvm); +#endif return 0; }