From 7103f60de8bed21a0ad5d15d2ad5b7a333dda201 Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Tue, 19 Aug 2014 16:45:56 +0200 Subject: KVM: avoid unnecessary synchronize_rcu We dont have to wait for a grace period if there is no oldpid that we are going to free. putpid also checks for NULL, so this patch only fences synchronize_rcu. Signed-off-by: Christian Borntraeger Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 33712fb26eb1..39b16035386f 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -129,7 +129,8 @@ int vcpu_load(struct kvm_vcpu *vcpu) struct pid *oldpid = vcpu->pid; struct pid *newpid = get_task_pid(current, PIDTYPE_PID); rcu_assign_pointer(vcpu->pid, newpid); - synchronize_rcu(); + if (oldpid) + synchronize_rcu(); put_pid(oldpid); } cpu = get_cpu(); -- cgit v1.2.3-58-ga151 From e790d9ef6405633b007339d746b709aed43a928d Mon Sep 17 00:00:00 2001 From: Radim Krčmář Date: Thu, 21 Aug 2014 18:08:05 +0200 Subject: KVM: add kvm_arch_sched_in MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Introduce preempt notifiers for architecture specific code. Advantage over creating a new notifier in every arch is slightly simpler code and guaranteed call order with respect to kvm_sched_in. Signed-off-by: Radim Krčmář Signed-off-by: Paolo Bonzini --- arch/arm/kvm/arm.c | 4 ++++ arch/mips/kvm/mips.c | 4 ++++ arch/powerpc/kvm/powerpc.c | 4 ++++ arch/s390/kvm/kvm-s390.c | 4 ++++ arch/x86/kvm/x86.c | 4 ++++ include/linux/kvm_host.h | 2 ++ virt/kvm/kvm_main.c | 2 ++ 7 files changed, 24 insertions(+) (limited to 'virt/kvm/kvm_main.c') diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index a99e0cdf8ba2..9f788ebac55b 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -288,6 +288,10 @@ void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) { } +void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) +{ +} + void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) { vcpu->cpu = cpu; diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c index cd7114147ae7..2362df2a79f9 100644 --- a/arch/mips/kvm/mips.c +++ b/arch/mips/kvm/mips.c @@ -1002,6 +1002,10 @@ void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) { } +void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) +{ +} + int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, struct kvm_translation *tr) { diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 4c79284b58be..cbc432f4f0a6 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -720,6 +720,10 @@ void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) kvmppc_subarch_vcpu_uninit(vcpu); } +void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) +{ +} + void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) { #ifdef CONFIG_BOOKE diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index ce81eb2ab76a..a3c324ec4370 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -555,6 +555,10 @@ void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) /* Nothing todo */ } +void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) +{ +} + void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) { save_fp_ctl(&vcpu->arch.host_fpregs.fpc); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index cd718c01cdf1..7d43dc7bb906 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -7171,6 +7171,10 @@ void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) static_key_slow_dec(&kvm_no_apic_vcpu); } +void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) +{ +} + int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) { if (type) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index a4c33b34fe3f..ebd723676633 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -624,6 +624,8 @@ void kvm_arch_exit(void); int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu); void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu); +void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu); + void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu); void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu); void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 39b16035386f..5a0817ee996e 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -3124,6 +3124,8 @@ static void kvm_sched_in(struct preempt_notifier *pn, int cpu) if (vcpu->preempted) vcpu->preempted = false; + kvm_arch_sched_in(vcpu, cpu); + kvm_arch_vcpu_load(vcpu, cpu); } -- cgit v1.2.3-58-ga151 From 64d831269ccbca1fc6d739a0f3c8aa24afb43a5e Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Tue, 19 Aug 2014 12:15:00 +0200 Subject: KVM: Introduce gfn_to_hva_memslot_prot To support read-only memory regions on arm and arm64, we have a need to resolve a gfn to an hva given a pointer to a memslot to avoid looping through the memslots twice and to reuse the hva error checking of gfn_to_hva_prot(), add a new gfn_to_hva_memslot_prot() function and refactor gfn_to_hva_prot() to use this function. Acked-by: Marc Zyngier Signed-off-by: Christoffer Dall --- include/linux/kvm_host.h | 2 ++ virt/kvm/kvm_main.c | 11 +++++++++-- 2 files changed, 11 insertions(+), 2 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index ebd723676633..6d8a658ec174 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -528,6 +528,8 @@ struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn); unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn); unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable); unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot, gfn_t gfn); +unsigned long gfn_to_hva_memslot_prot(struct kvm_memory_slot *slot, gfn_t gfn, + bool *writable); void kvm_release_page_clean(struct page *page); void kvm_release_page_dirty(struct page *page); void kvm_set_page_accessed(struct page *page); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 5a0817ee996e..76c92a7249c4 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1076,9 +1076,9 @@ EXPORT_SYMBOL_GPL(gfn_to_hva); * If writable is set to false, the hva returned by this function is only * allowed to be read. */ -unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable) +unsigned long gfn_to_hva_memslot_prot(struct kvm_memory_slot *slot, + gfn_t gfn, bool *writable) { - struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn); unsigned long hva = __gfn_to_hva_many(slot, gfn, NULL, false); if (!kvm_is_error_hva(hva) && writable) @@ -1087,6 +1087,13 @@ unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable) return hva; } +unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable) +{ + struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn); + + return gfn_to_hva_memslot_prot(slot, gfn, writable); +} + static int kvm_read_hva(void *data, void __user *hva, int len) { return __copy_from_user(data, hva, len); -- cgit v1.2.3-58-ga151 From 0f8a4de3e088797576ac76200b634b802e5c7781 Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Tue, 26 Aug 2014 14:00:37 +0200 Subject: KVM: Unconditionally export KVM_CAP_READONLY_MEM The idea between capabilities and the KVM_CHECK_EXTENSION ioctl is that userspace can, at run-time, determine if a feature is supported or not. This allows KVM to being supporting a new feature with a new kernel version without any need to update user space. Unfortunately, since the definition of KVM_CAP_READONLY_MEM was guarded by #ifdef __KVM_HAVE_READONLY_MEM, such discovery still required a user space update. Therefore, unconditionally export KVM_CAP_READONLY_MEM and change the in-kernel conditional to rely on __KVM_HAVE_READONLY_MEM. Signed-off-by: Christoffer Dall Signed-off-by: Paolo Bonzini --- include/uapi/linux/kvm.h | 2 -- virt/kvm/kvm_main.c | 2 +- 2 files changed, 1 insertion(+), 3 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index cf3a2ff440e4..90d3edab839c 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -738,9 +738,7 @@ struct kvm_ppc_smmu_info { #define KVM_CAP_PPC_GET_SMMU_INFO 78 #define KVM_CAP_S390_COW 79 #define KVM_CAP_PPC_ALLOC_HTAB 80 -#ifdef __KVM_HAVE_READONLY_MEM #define KVM_CAP_READONLY_MEM 81 -#endif #define KVM_CAP_IRQFD_RESAMPLE 82 #define KVM_CAP_PPC_BOOKE_WATCHDOG 83 #define KVM_CAP_PPC_HTAB_FD 84 diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 5a0817ee996e..1d03967def40 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -708,7 +708,7 @@ static int check_memory_region_flags(struct kvm_userspace_memory_region *mem) { u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES; -#ifdef KVM_CAP_READONLY_MEM +#ifdef __KVM_HAVE_READONLY_MEM valid_flags |= KVM_MEM_READONLY; #endif -- cgit v1.2.3-58-ga151 From 13a34e067eab24fec882e1834fbf2cc31911d474 Mon Sep 17 00:00:00 2001 From: Radim Krčmář Date: Thu, 28 Aug 2014 15:13:03 +0200 Subject: KVM: remove garbage arg to *hardware_{en,dis}able MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In the beggining was on_each_cpu(), which required an unused argument to kvm_arch_ops.hardware_{en,dis}able, but this was soon forgotten. Remove unnecessary arguments that stem from this. Signed-off-by: Radim Krčmář Signed-off-by: Paolo Bonzini --- arch/arm/include/asm/kvm_host.h | 2 +- arch/arm/kvm/arm.c | 2 +- arch/arm64/include/asm/kvm_host.h | 2 +- arch/ia64/kvm/kvm-ia64.c | 4 ++-- arch/mips/include/asm/kvm_host.h | 2 +- arch/mips/kvm/mips.c | 2 +- arch/powerpc/include/asm/kvm_host.h | 2 +- arch/powerpc/kvm/powerpc.c | 2 +- arch/s390/include/asm/kvm_host.h | 2 +- arch/s390/kvm/kvm-s390.c | 2 +- arch/x86/include/asm/kvm_host.h | 4 ++-- arch/x86/kvm/svm.c | 4 ++-- arch/x86/kvm/vmx.c | 4 ++-- arch/x86/kvm/x86.c | 12 ++++++------ include/linux/kvm_host.h | 4 ++-- virt/kvm/kvm_main.c | 4 ++-- 16 files changed, 27 insertions(+), 27 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index aea259e9431f..032a8538318a 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -230,7 +230,7 @@ static inline void vgic_arch_setup(const struct vgic_params *vgic) int kvm_perf_init(void); int kvm_perf_teardown(void); -static inline void kvm_arch_hardware_disable(void *garbage) {} +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_vcpu_uninit(struct kvm_vcpu *vcpu) {} diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 132bb0d9c5ad..005a7b5fd0aa 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -87,7 +87,7 @@ struct kvm_vcpu __percpu **kvm_get_running_vcpus(void) return &kvm_arm_running_vcpu; } -int kvm_arch_hardware_enable(void *garbage) +int kvm_arch_hardware_enable(void) { return 0; } diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index b5045e3e05f8..be9970a59497 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -242,7 +242,7 @@ static inline void vgic_arch_setup(const struct vgic_params *vgic) } } -static inline void kvm_arch_hardware_disable(void *garbage) {} +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_vcpu_uninit(struct kvm_vcpu *vcpu) {} diff --git a/arch/ia64/kvm/kvm-ia64.c b/arch/ia64/kvm/kvm-ia64.c index 5e14dcaf844e..ec6b9acb6bea 100644 --- a/arch/ia64/kvm/kvm-ia64.c +++ b/arch/ia64/kvm/kvm-ia64.c @@ -125,7 +125,7 @@ long ia64_pal_vp_create(u64 *vpd, u64 *host_iva, u64 *opt_handler) static DEFINE_SPINLOCK(vp_lock); -int kvm_arch_hardware_enable(void *garbage) +int kvm_arch_hardware_enable(void) { long status; long tmp_base; @@ -160,7 +160,7 @@ int kvm_arch_hardware_enable(void *garbage) return 0; } -void kvm_arch_hardware_disable(void *garbage) +void kvm_arch_hardware_disable(void) { long status; diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h index 0b24d6622ec1..f2c249796ea8 100644 --- a/arch/mips/include/asm/kvm_host.h +++ b/arch/mips/include/asm/kvm_host.h @@ -762,7 +762,7 @@ extern int kvm_mips_trans_mtc0(uint32_t inst, uint32_t *opc, extern void kvm_mips_dump_stats(struct kvm_vcpu *vcpu); extern unsigned long kvm_mips_get_ramsize(struct kvm *kvm); -static inline void kvm_arch_hardware_disable(void *garbage) {} +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_free_memslot(struct kvm *kvm, diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c index 0ec7490d70bd..e3b21e51ff7e 100644 --- a/arch/mips/kvm/mips.c +++ b/arch/mips/kvm/mips.c @@ -77,7 +77,7 @@ int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu) return 1; } -int kvm_arch_hardware_enable(void *garbage) +int kvm_arch_hardware_enable(void) { return 0; } diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 237cc0cc80a2..604000882352 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -682,7 +682,7 @@ struct kvm_vcpu_arch { #define __KVM_HAVE_ARCH_WQP #define __KVM_HAVE_CREATE_DEVICE -static inline void kvm_arch_hardware_disable(void *garbage) {} +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) {} diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 72c3fc085207..da505237a664 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -384,7 +384,7 @@ int kvmppc_ld(struct kvm_vcpu *vcpu, ulong *eaddr, int size, void *ptr, } EXPORT_SYMBOL_GPL(kvmppc_ld); -int kvm_arch_hardware_enable(void *garbage) +int kvm_arch_hardware_enable(void) { return 0; } diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h index f6dd90684b97..a76a124dff48 100644 --- a/arch/s390/include/asm/kvm_host.h +++ b/arch/s390/include/asm/kvm_host.h @@ -452,7 +452,7 @@ void kvm_arch_async_page_present(struct kvm_vcpu *vcpu, extern int sie64a(struct kvm_s390_sie_block *, u64 *); extern char sie_exit; -static inline void kvm_arch_hardware_disable(void *garbage) {} +static inline void kvm_arch_hardware_disable(void) {} static inline void kvm_arch_check_processor_compat(void *rtn) {} static inline void kvm_arch_exit(void) {} static inline void kvm_arch_sync_events(struct kvm *kvm) {} diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index b8fe1ae777db..628e992eeded 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -100,7 +100,7 @@ int test_vfacility(unsigned long nr) } /* Section: not file related */ -int kvm_arch_hardware_enable(void *garbage) +int kvm_arch_hardware_enable(void) { /* every s390 is virtualization enabled ;-) */ return 0; diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 567fface45f8..73e4149eda33 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -661,8 +661,8 @@ struct msr_data { struct kvm_x86_ops { int (*cpu_has_kvm_support)(void); /* __init */ int (*disabled_by_bios)(void); /* __init */ - int (*hardware_enable)(void *dummy); - void (*hardware_disable)(void *dummy); + int (*hardware_enable)(void); + void (*hardware_disable)(void); void (*check_processor_compatibility)(void *rtn); int (*hardware_setup)(void); /* __init */ void (*hardware_unsetup)(void); /* __exit */ diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 7cd230e55118..8ef704037370 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -622,7 +622,7 @@ static int has_svm(void) return 1; } -static void svm_hardware_disable(void *garbage) +static void svm_hardware_disable(void) { /* Make sure we clean up behind us */ if (static_cpu_has(X86_FEATURE_TSCRATEMSR)) @@ -633,7 +633,7 @@ static void svm_hardware_disable(void *garbage) amd_pmu_disable_virt(); } -static int svm_hardware_enable(void *garbage) +static int svm_hardware_enable(void) { struct svm_cpu_data *sd; diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index d70550d0bcff..671ca5edc709 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -2728,7 +2728,7 @@ static void kvm_cpu_vmxon(u64 addr) : "memory", "cc"); } -static int hardware_enable(void *garbage) +static int hardware_enable(void) { int cpu = raw_smp_processor_id(); u64 phys_addr = __pa(per_cpu(vmxarea, cpu)); @@ -2792,7 +2792,7 @@ static void kvm_cpu_vmxoff(void) asm volatile (__ex(ASM_VMX_VMXOFF) : : : "cc"); } -static void hardware_disable(void *garbage) +static void hardware_disable(void) { if (vmm_exclusive) { vmclear_local_loaded_vmcss(); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index c10408ef9ab1..a375dfc42f6a 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -246,7 +246,7 @@ void kvm_set_shared_msr(unsigned slot, u64 value, u64 mask) } EXPORT_SYMBOL_GPL(kvm_set_shared_msr); -static void drop_user_return_notifiers(void *ignore) +static void drop_user_return_notifiers(void) { unsigned int cpu = smp_processor_id(); struct kvm_shared_msrs *smsr = per_cpu_ptr(shared_msrs, cpu); @@ -6959,7 +6959,7 @@ void kvm_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, unsigned int vector) kvm_rip_write(vcpu, 0); } -int kvm_arch_hardware_enable(void *garbage) +int kvm_arch_hardware_enable(void) { struct kvm *kvm; struct kvm_vcpu *vcpu; @@ -6970,7 +6970,7 @@ int kvm_arch_hardware_enable(void *garbage) bool stable, backwards_tsc = false; kvm_shared_msr_cpu_online(); - ret = kvm_x86_ops->hardware_enable(garbage); + ret = kvm_x86_ops->hardware_enable(); if (ret != 0) return ret; @@ -7051,10 +7051,10 @@ int kvm_arch_hardware_enable(void *garbage) return 0; } -void kvm_arch_hardware_disable(void *garbage) +void kvm_arch_hardware_disable(void) { - kvm_x86_ops->hardware_disable(garbage); - drop_user_return_notifiers(garbage); + kvm_x86_ops->hardware_disable(); + drop_user_return_notifiers(); } int kvm_arch_hardware_setup(void) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index e1cb915a1096..e098dce179df 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -630,8 +630,8 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu); int kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu); void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu); -int kvm_arch_hardware_enable(void *garbage); -void kvm_arch_hardware_disable(void *garbage); +int kvm_arch_hardware_enable(void); +void kvm_arch_hardware_disable(void); int kvm_arch_hardware_setup(void); void kvm_arch_hardware_unsetup(void); void kvm_arch_check_processor_compat(void *rtn); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 1d03967def40..7176929a4cda 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2669,7 +2669,7 @@ static void hardware_enable_nolock(void *junk) cpumask_set_cpu(cpu, cpus_hardware_enabled); - r = kvm_arch_hardware_enable(NULL); + r = kvm_arch_hardware_enable(); if (r) { cpumask_clear_cpu(cpu, cpus_hardware_enabled); @@ -2694,7 +2694,7 @@ static void hardware_disable_nolock(void *junk) if (!cpumask_test_cpu(cpu, cpus_hardware_enabled)) return; cpumask_clear_cpu(cpu, cpus_hardware_enabled); - kvm_arch_hardware_disable(NULL); + kvm_arch_hardware_disable(); } static void hardware_disable(void) -- cgit v1.2.3-58-ga151 From 00f034a12fdd81210d58116326d92780aac5c238 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Wed, 20 Aug 2014 14:29:21 +0200 Subject: KVM: do not bias the generation number in kvm_current_mmio_generation The next patch will give a meaning (a la seqcount) to the low bit of the generation number. Ensure that it matches between kvm->memslots->generation and kvm_current_mmio_generation(). Cc: stable@vger.kernel.org Reviewed-by: David Matlack Reviewed-by: Xiao Guangrong Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu.c | 7 +------ virt/kvm/kvm_main.c | 7 +++++++ 2 files changed, 8 insertions(+), 6 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 931467881da7..323c3f5f5c84 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -236,12 +236,7 @@ static unsigned int get_mmio_spte_generation(u64 spte) static unsigned int kvm_current_mmio_generation(struct kvm *kvm) { - /* - * Init kvm generation close to MMIO_MAX_GEN to easily test the - * code of handling generation number wrap-around. - */ - return (kvm_memslots(kvm)->generation + - MMIO_MAX_GEN - 150) & MMIO_GEN_MASK; + return kvm_memslots(kvm)->generation & MMIO_GEN_MASK; } static void mark_mmio_spte(struct kvm *kvm, u64 *sptep, u64 gfn, diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 7176929a4cda..0bfdb673db26 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -477,6 +477,13 @@ static struct kvm *kvm_create_vm(unsigned long type) kvm->memslots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL); if (!kvm->memslots) goto out_err_no_srcu; + + /* + * Init kvm generation close to the maximum to easily test the + * code of handling generation number wrap-around. + */ + kvm->memslots->generation = -150; + kvm_init_memslots_id(kvm); if (init_srcu_struct(&kvm->srcu)) goto out_err_no_srcu; -- cgit v1.2.3-58-ga151 From ee3d1570b58677885b4552bce8217fda7b226a68 Mon Sep 17 00:00:00 2001 From: David Matlack Date: Mon, 18 Aug 2014 15:46:06 -0700 Subject: kvm: fix potentially corrupt mmio cache vcpu exits and memslot mutations can run concurrently as long as the vcpu does not aquire the slots mutex. Thus it is theoretically possible for memslots to change underneath a vcpu that is handling an exit. If we increment the memslot generation number again after synchronize_srcu_expedited(), vcpus can safely cache memslot generation without maintaining a single rcu_dereference through an entire vm exit. And much of the x86/kvm code does not maintain a single rcu_dereference of the current memslots during each exit. We can prevent the following case: vcpu (CPU 0) | thread (CPU 1) --------------------------------------------+-------------------------- 1 vm exit | 2 srcu_read_unlock(&kvm->srcu) | 3 decide to cache something based on | old memslots | 4 | change memslots | (increments generation) 5 | synchronize_srcu(&kvm->srcu); 6 retrieve generation # from new memslots | 7 tag cache with new memslot generation | 8 srcu_read_unlock(&kvm->srcu) | ... | | ... | | | By incrementing the generation after synchronizing with kvm->srcu readers, we ensure that the generation retrieved in (6) will become invalid soon after (8). Keeping the existing increment is not strictly necessary, but we do keep it and just move it for consistency from update_memslots to install_new_memslots. It invalidates old cached MMIOs immediately, instead of having to wait for the end of synchronize_srcu_expedited, which makes the code more clearly correct in case CPU 1 is preempted right after synchronize_srcu() returns. To avoid halving the generation space in SPTEs, always presume that the low bit of the generation is zero when reconstructing a generation number out of an SPTE. This effectively disables MMIO caching in SPTEs during the call to synchronize_srcu_expedited. Using the low bit this way is somewhat like a seqcount---where the protected thing is a cache, and instead of retrying we can simply punt if we observe the low bit to be 1. Cc: stable@vger.kernel.org Signed-off-by: David Matlack Reviewed-by: Xiao Guangrong Reviewed-by: David Matlack Signed-off-by: Paolo Bonzini --- Documentation/virtual/kvm/mmu.txt | 14 ++++++++++++++ arch/x86/kvm/mmu.c | 20 ++++++++++++-------- virt/kvm/kvm_main.c | 23 ++++++++++++++++------- 3 files changed, 42 insertions(+), 15 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/Documentation/virtual/kvm/mmu.txt b/Documentation/virtual/kvm/mmu.txt index 290894176142..53838d9c6295 100644 --- a/Documentation/virtual/kvm/mmu.txt +++ b/Documentation/virtual/kvm/mmu.txt @@ -425,6 +425,20 @@ fault through the slow path. Since only 19 bits are used to store generation-number on mmio spte, all pages are zapped when there is an overflow. +Unfortunately, a single memory access might access kvm_memslots(kvm) multiple +times, the last one happening when the generation number is retrieved and +stored into the MMIO spte. Thus, the MMIO spte might be created based on +out-of-date information, but with an up-to-date generation number. + +To avoid this, the generation number is incremented again after synchronize_srcu +returns; thus, the low bit of kvm_memslots(kvm)->generation is only 1 during a +memslot update, while some SRCU readers might be using the old copy. We do not +want to use an MMIO sptes created with an odd generation number, and we can do +this without losing a bit in the MMIO spte. The low bit of the generation +is not stored in MMIO spte, and presumed zero when it is extracted out of the +spte. If KVM is unlucky and creates an MMIO spte while the low bit is 1, +the next access to the spte will always be a cache miss. + Further reading =============== diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 323c3f5f5c84..96515957ba82 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -199,16 +199,20 @@ void kvm_mmu_set_mmio_spte_mask(u64 mmio_mask) EXPORT_SYMBOL_GPL(kvm_mmu_set_mmio_spte_mask); /* - * spte bits of bit 3 ~ bit 11 are used as low 9 bits of generation number, - * the bits of bits 52 ~ bit 61 are used as high 10 bits of generation - * number. + * the low bit of the generation number is always presumed to be zero. + * This disables mmio caching during memslot updates. The concept is + * similar to a seqcount but instead of retrying the access we just punt + * and ignore the cache. + * + * spte bits 3-11 are used as bits 1-9 of the generation number, + * the bits 52-61 are used as bits 10-19 of the generation number. */ -#define MMIO_SPTE_GEN_LOW_SHIFT 3 +#define MMIO_SPTE_GEN_LOW_SHIFT 2 #define MMIO_SPTE_GEN_HIGH_SHIFT 52 -#define MMIO_GEN_SHIFT 19 -#define MMIO_GEN_LOW_SHIFT 9 -#define MMIO_GEN_LOW_MASK ((1 << MMIO_GEN_LOW_SHIFT) - 1) +#define MMIO_GEN_SHIFT 20 +#define MMIO_GEN_LOW_SHIFT 10 +#define MMIO_GEN_LOW_MASK ((1 << MMIO_GEN_LOW_SHIFT) - 2) #define MMIO_GEN_MASK ((1 << MMIO_GEN_SHIFT) - 1) #define MMIO_MAX_GEN ((1 << MMIO_GEN_SHIFT) - 1) @@ -4428,7 +4432,7 @@ void kvm_mmu_invalidate_mmio_sptes(struct kvm *kvm) * The very rare case: if the generation-number is round, * zap all shadow pages. */ - if (unlikely(kvm_current_mmio_generation(kvm) >= MMIO_MAX_GEN)) { + if (unlikely(kvm_current_mmio_generation(kvm) == 0)) { printk_ratelimited(KERN_INFO "kvm: zapping shadow pages for mmio generation wraparound\n"); kvm_mmu_invalidate_zap_all_pages(kvm); } diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 0bfdb673db26..bb8641b5d83b 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -95,8 +95,6 @@ static int hardware_enable_all(void); static void hardware_disable_all(void); static void kvm_io_bus_destroy(struct kvm_io_bus *bus); -static void update_memslots(struct kvm_memslots *slots, - struct kvm_memory_slot *new, u64 last_generation); static void kvm_release_pfn_dirty(pfn_t pfn); static void mark_page_dirty_in_slot(struct kvm *kvm, @@ -695,8 +693,7 @@ static void sort_memslots(struct kvm_memslots *slots) } static void update_memslots(struct kvm_memslots *slots, - struct kvm_memory_slot *new, - u64 last_generation) + struct kvm_memory_slot *new) { if (new) { int id = new->id; @@ -707,8 +704,6 @@ static void update_memslots(struct kvm_memslots *slots, if (new->npages != npages) sort_memslots(slots); } - - slots->generation = last_generation + 1; } static int check_memory_region_flags(struct kvm_userspace_memory_region *mem) @@ -730,10 +725,24 @@ static struct kvm_memslots *install_new_memslots(struct kvm *kvm, { struct kvm_memslots *old_memslots = kvm->memslots; - update_memslots(slots, new, kvm->memslots->generation); + /* + * Set the low bit in the generation, which disables SPTE caching + * until the end of synchronize_srcu_expedited. + */ + WARN_ON(old_memslots->generation & 1); + slots->generation = old_memslots->generation + 1; + + update_memslots(slots, new); rcu_assign_pointer(kvm->memslots, slots); synchronize_srcu_expedited(&kvm->srcu); + /* + * Increment the new memslot generation a second time. This prevents + * vm exits that race with memslot updates from caching a memslot + * generation that will (potentially) be valid forever. + */ + slots->generation++; + kvm_arch_memslots_updated(kvm); return old_memslots; -- cgit v1.2.3-58-ga151 From 34656113182b704682e23d1363417536addfec97 Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Thu, 4 Sep 2014 21:13:31 +0200 Subject: KVM: remove redundant check of in_spin_loop The expression `vcpu->spin_loop.in_spin_loop' is always true, because it is evaluated only when the condition `!vcpu->spin_loop.in_spin_loop' is false. Signed-off-by: Christian Borntraeger Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index bb8641b5d83b..cc7bd286d135 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1785,8 +1785,7 @@ static bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu *vcpu) bool eligible; eligible = !vcpu->spin_loop.in_spin_loop || - (vcpu->spin_loop.in_spin_loop && - vcpu->spin_loop.dy_eligible); + vcpu->spin_loop.dy_eligible; if (vcpu->spin_loop.in_spin_loop) kvm_vcpu_set_dy_eligible(vcpu, !vcpu->spin_loop.dy_eligible); -- cgit v1.2.3-58-ga151 From a13f533b2f1d53a7c0baa7490498caeab7bc8ba5 Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Thu, 4 Sep 2014 21:13:32 +0200 Subject: KVM: remove redundant assigment of return value in kvm_dev_ioctl The first statement of kvm_dev_ioctl is long r = -EINVAL; No need to reassign the same value. Signed-off-by: Christian Borntraeger Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index cc7bd286d135..de1ae82ba192 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2627,7 +2627,6 @@ static long kvm_dev_ioctl(struct file *filp, switch (ioctl) { case KVM_GET_API_VERSION: - r = -EINVAL; if (arg) goto out; r = KVM_API_VERSION; @@ -2639,7 +2638,6 @@ static long kvm_dev_ioctl(struct file *filp, r = kvm_vm_ioctl_check_extension_generic(NULL, arg); break; case KVM_GET_VCPU_MMAP_SIZE: - r = -EINVAL; if (arg) goto out; r = PAGE_SIZE; /* struct kvm_run */ -- cgit v1.2.3-58-ga151 From f2a25160887e00434ce1361007009120e1fecbda Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Thu, 4 Sep 2014 21:13:33 +0200 Subject: KVM: remove redundant assignments in __kvm_set_memory_region __kvm_set_memory_region sets r to EINVAL very early. Doing it again is not necessary. The same is true later on, where r is assigned -ENOMEM twice. Signed-off-by: Christian Borntraeger Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 3 --- 1 file changed, 3 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index de1ae82ba192..c338599804e0 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -793,7 +793,6 @@ int __kvm_set_memory_region(struct kvm *kvm, base_gfn = mem->guest_phys_addr >> PAGE_SHIFT; npages = mem->memory_size >> PAGE_SHIFT; - r = -EINVAL; if (npages > KVM_MEM_MAX_NR_PAGES) goto out; @@ -807,7 +806,6 @@ int __kvm_set_memory_region(struct kvm *kvm, new.npages = npages; new.flags = mem->flags; - r = -EINVAL; if (npages) { if (!old.npages) change = KVM_MR_CREATE; @@ -863,7 +861,6 @@ int __kvm_set_memory_region(struct kvm *kvm, } if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) { - r = -ENOMEM; slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots), GFP_KERNEL); if (!slots) -- cgit v1.2.3-58-ga151 From d60eacb07053142bfb9b41582074a89a790a9d46 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Tue, 2 Sep 2014 10:27:33 +0100 Subject: KVM: device: add simple registration mechanism for kvm_device_ops kvm_ioctl_create_device currently has knowledge of all the device types and their associated ops. This is fairly inflexible when adding support for new in-kernel device emulations, so move what we currently have out into a table, which can support dynamic registration of ops by new drivers for virtual hardware. Cc: Alex Williamson Cc: Alex Graf Cc: Gleb Natapov Cc: Paolo Bonzini Cc: Marc Zyngier Acked-by: Cornelia Huck Reviewed-by: Christoffer Dall Signed-off-by: Will Deacon Signed-off-by: Paolo Bonzini --- include/linux/kvm_host.h | 1 + include/uapi/linux/kvm.h | 22 +++++++++++----- virt/kvm/kvm_main.c | 65 ++++++++++++++++++++++++++++-------------------- 3 files changed, 55 insertions(+), 33 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index e098dce179df..b6e954742951 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1064,6 +1064,7 @@ struct kvm_device_ops { void kvm_device_get(struct kvm_device *dev); void kvm_device_put(struct kvm_device *dev); struct kvm_device *kvm_device_from_filp(struct file *filp); +int kvm_register_device_ops(struct kvm_device_ops *ops, u32 type); extern struct kvm_device_ops kvm_mpic_ops; extern struct kvm_device_ops kvm_xics_ops; diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 0695a1e3e332..60768822b140 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -943,15 +943,25 @@ struct kvm_device_attr { __u64 addr; /* userspace address of attr data */ }; -#define KVM_DEV_TYPE_FSL_MPIC_20 1 -#define KVM_DEV_TYPE_FSL_MPIC_42 2 -#define KVM_DEV_TYPE_XICS 3 -#define KVM_DEV_TYPE_VFIO 4 #define KVM_DEV_VFIO_GROUP 1 #define KVM_DEV_VFIO_GROUP_ADD 1 #define KVM_DEV_VFIO_GROUP_DEL 2 -#define KVM_DEV_TYPE_ARM_VGIC_V2 5 -#define KVM_DEV_TYPE_FLIC 6 + +enum kvm_device_type { + KVM_DEV_TYPE_FSL_MPIC_20 = 1, +#define KVM_DEV_TYPE_FSL_MPIC_20 KVM_DEV_TYPE_FSL_MPIC_20 + KVM_DEV_TYPE_FSL_MPIC_42, +#define KVM_DEV_TYPE_FSL_MPIC_42 KVM_DEV_TYPE_FSL_MPIC_42 + KVM_DEV_TYPE_XICS, +#define KVM_DEV_TYPE_XICS KVM_DEV_TYPE_XICS + KVM_DEV_TYPE_VFIO, +#define KVM_DEV_TYPE_VFIO KVM_DEV_TYPE_VFIO + KVM_DEV_TYPE_ARM_VGIC_V2, +#define KVM_DEV_TYPE_ARM_VGIC_V2 KVM_DEV_TYPE_ARM_VGIC_V2 + KVM_DEV_TYPE_FLIC, +#define KVM_DEV_TYPE_FLIC KVM_DEV_TYPE_FLIC + KVM_DEV_TYPE_MAX, +}; /* * ioctls for VM fds diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index c338599804e0..686d783387a0 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2272,44 +2272,55 @@ struct kvm_device *kvm_device_from_filp(struct file *filp) return filp->private_data; } -static int kvm_ioctl_create_device(struct kvm *kvm, - struct kvm_create_device *cd) -{ - struct kvm_device_ops *ops = NULL; - struct kvm_device *dev; - bool test = cd->flags & KVM_CREATE_DEVICE_TEST; - int ret; - - switch (cd->type) { +static struct kvm_device_ops *kvm_device_ops_table[KVM_DEV_TYPE_MAX] = { #ifdef CONFIG_KVM_MPIC - case KVM_DEV_TYPE_FSL_MPIC_20: - case KVM_DEV_TYPE_FSL_MPIC_42: - ops = &kvm_mpic_ops; - break; + [KVM_DEV_TYPE_FSL_MPIC_20] = &kvm_mpic_ops, + [KVM_DEV_TYPE_FSL_MPIC_42] = &kvm_mpic_ops, #endif + #ifdef CONFIG_KVM_XICS - case KVM_DEV_TYPE_XICS: - ops = &kvm_xics_ops; - break; + [KVM_DEV_TYPE_XICS] = &kvm_xics_ops, #endif + #ifdef CONFIG_KVM_VFIO - case KVM_DEV_TYPE_VFIO: - ops = &kvm_vfio_ops; - break; + [KVM_DEV_TYPE_VFIO] = &kvm_vfio_ops, #endif + #ifdef CONFIG_KVM_ARM_VGIC - case KVM_DEV_TYPE_ARM_VGIC_V2: - ops = &kvm_arm_vgic_v2_ops; - break; + [KVM_DEV_TYPE_ARM_VGIC_V2] = &kvm_arm_vgic_v2_ops, #endif + #ifdef CONFIG_S390 - case KVM_DEV_TYPE_FLIC: - ops = &kvm_flic_ops; - break; + [KVM_DEV_TYPE_FLIC] = &kvm_flic_ops, #endif - default: +}; + +int kvm_register_device_ops(struct kvm_device_ops *ops, u32 type) +{ + if (type >= ARRAY_SIZE(kvm_device_ops_table)) + return -ENOSPC; + + if (kvm_device_ops_table[type] != NULL) + return -EEXIST; + + kvm_device_ops_table[type] = ops; + return 0; +} + +static int kvm_ioctl_create_device(struct kvm *kvm, + struct kvm_create_device *cd) +{ + struct kvm_device_ops *ops = NULL; + struct kvm_device *dev; + bool test = cd->flags & KVM_CREATE_DEVICE_TEST; + int ret; + + if (cd->type >= ARRAY_SIZE(kvm_device_ops_table)) + return -ENODEV; + + ops = kvm_device_ops_table[cd->type]; + if (ops == NULL) return -ENODEV; - } if (test) return 0; -- cgit v1.2.3-58-ga151 From c06a841bf36340e9e917ce60d11a6425ac85d0bd Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Tue, 2 Sep 2014 10:27:34 +0100 Subject: KVM: ARM: vgic: register kvm_device_ops dynamically Now that we have a dynamic means to register kvm_device_ops, use that for the ARM VGIC, instead of relying on the static table. Cc: Gleb Natapov Cc: Paolo Bonzini Acked-by: Marc Zyngier Reviewed-by: Christoffer Dall Signed-off-by: Will Deacon Signed-off-by: Paolo Bonzini --- include/linux/kvm_host.h | 1 - virt/kvm/arm/vgic.c | 157 ++++++++++++++++++++++++----------------------- virt/kvm/kvm_main.c | 4 -- 3 files changed, 79 insertions(+), 83 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index b6e954742951..601d321f96e7 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1069,7 +1069,6 @@ int kvm_register_device_ops(struct kvm_device_ops *ops, u32 type); extern struct kvm_device_ops kvm_mpic_ops; extern struct kvm_device_ops kvm_xics_ops; extern struct kvm_device_ops kvm_vfio_ops; -extern struct kvm_device_ops kvm_arm_vgic_v2_ops; extern struct kvm_device_ops kvm_flic_ops; #ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index 73eba793b17f..3ee3ce06bbec 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -1522,83 +1522,6 @@ int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu) return 0; } -static void vgic_init_maintenance_interrupt(void *info) -{ - enable_percpu_irq(vgic->maint_irq, 0); -} - -static int vgic_cpu_notify(struct notifier_block *self, - unsigned long action, void *cpu) -{ - switch (action) { - case CPU_STARTING: - case CPU_STARTING_FROZEN: - vgic_init_maintenance_interrupt(NULL); - break; - case CPU_DYING: - case CPU_DYING_FROZEN: - disable_percpu_irq(vgic->maint_irq); - break; - } - - return NOTIFY_OK; -} - -static struct notifier_block vgic_cpu_nb = { - .notifier_call = vgic_cpu_notify, -}; - -static const struct of_device_id vgic_ids[] = { - { .compatible = "arm,cortex-a15-gic", .data = vgic_v2_probe, }, - { .compatible = "arm,gic-v3", .data = vgic_v3_probe, }, - {}, -}; - -int kvm_vgic_hyp_init(void) -{ - const struct of_device_id *matched_id; - int (*vgic_probe)(struct device_node *,const struct vgic_ops **, - const struct vgic_params **); - struct device_node *vgic_node; - int ret; - - vgic_node = of_find_matching_node_and_match(NULL, - vgic_ids, &matched_id); - if (!vgic_node) { - kvm_err("error: no compatible GIC node found\n"); - return -ENODEV; - } - - vgic_probe = matched_id->data; - ret = vgic_probe(vgic_node, &vgic_ops, &vgic); - if (ret) - return ret; - - ret = request_percpu_irq(vgic->maint_irq, vgic_maintenance_handler, - "vgic", kvm_get_running_vcpus()); - if (ret) { - kvm_err("Cannot register interrupt %d\n", vgic->maint_irq); - return ret; - } - - ret = __register_cpu_notifier(&vgic_cpu_nb); - if (ret) { - kvm_err("Cannot register vgic CPU notifier\n"); - goto out_free_irq; - } - - /* Callback into for arch code for setup */ - vgic_arch_setup(vgic); - - on_each_cpu(vgic_init_maintenance_interrupt, NULL, 1); - - return 0; - -out_free_irq: - free_percpu_irq(vgic->maint_irq, kvm_get_running_vcpus()); - return ret; -} - /** * kvm_vgic_init - Initialize global VGIC state before running any VCPUs * @kvm: pointer to the kvm struct @@ -2062,7 +1985,7 @@ static int vgic_create(struct kvm_device *dev, u32 type) return kvm_vgic_create(dev->kvm); } -struct kvm_device_ops kvm_arm_vgic_v2_ops = { +static struct kvm_device_ops kvm_arm_vgic_v2_ops = { .name = "kvm-arm-vgic", .create = vgic_create, .destroy = vgic_destroy, @@ -2070,3 +1993,81 @@ struct kvm_device_ops kvm_arm_vgic_v2_ops = { .get_attr = vgic_get_attr, .has_attr = vgic_has_attr, }; + +static void vgic_init_maintenance_interrupt(void *info) +{ + enable_percpu_irq(vgic->maint_irq, 0); +} + +static int vgic_cpu_notify(struct notifier_block *self, + unsigned long action, void *cpu) +{ + switch (action) { + case CPU_STARTING: + case CPU_STARTING_FROZEN: + vgic_init_maintenance_interrupt(NULL); + break; + case CPU_DYING: + case CPU_DYING_FROZEN: + disable_percpu_irq(vgic->maint_irq); + break; + } + + return NOTIFY_OK; +} + +static struct notifier_block vgic_cpu_nb = { + .notifier_call = vgic_cpu_notify, +}; + +static const struct of_device_id vgic_ids[] = { + { .compatible = "arm,cortex-a15-gic", .data = vgic_v2_probe, }, + { .compatible = "arm,gic-v3", .data = vgic_v3_probe, }, + {}, +}; + +int kvm_vgic_hyp_init(void) +{ + const struct of_device_id *matched_id; + int (*vgic_probe)(struct device_node *,const struct vgic_ops **, + const struct vgic_params **); + struct device_node *vgic_node; + int ret; + + vgic_node = of_find_matching_node_and_match(NULL, + vgic_ids, &matched_id); + if (!vgic_node) { + kvm_err("error: no compatible GIC node found\n"); + return -ENODEV; + } + + vgic_probe = matched_id->data; + ret = vgic_probe(vgic_node, &vgic_ops, &vgic); + if (ret) + return ret; + + ret = request_percpu_irq(vgic->maint_irq, vgic_maintenance_handler, + "vgic", kvm_get_running_vcpus()); + if (ret) { + kvm_err("Cannot register interrupt %d\n", vgic->maint_irq); + return ret; + } + + ret = __register_cpu_notifier(&vgic_cpu_nb); + if (ret) { + kvm_err("Cannot register vgic CPU notifier\n"); + goto out_free_irq; + } + + /* Callback into for arch code for setup */ + vgic_arch_setup(vgic); + + on_each_cpu(vgic_init_maintenance_interrupt, NULL, 1); + + return kvm_register_device_ops(&kvm_arm_vgic_v2_ops, + KVM_DEV_TYPE_ARM_VGIC_V2); + +out_free_irq: + free_percpu_irq(vgic->maint_irq, kvm_get_running_vcpus()); + return ret; +} diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 686d783387a0..68d96f5dbfe2 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2286,10 +2286,6 @@ static struct kvm_device_ops *kvm_device_ops_table[KVM_DEV_TYPE_MAX] = { [KVM_DEV_TYPE_VFIO] = &kvm_vfio_ops, #endif -#ifdef CONFIG_KVM_ARM_VGIC - [KVM_DEV_TYPE_ARM_VGIC_V2] = &kvm_arm_vgic_v2_ops, -#endif - #ifdef CONFIG_S390 [KVM_DEV_TYPE_FLIC] = &kvm_flic_ops, #endif -- cgit v1.2.3-58-ga151 From 84877d93336de21a6251db00b841468a83c65906 Mon Sep 17 00:00:00 2001 From: Cornelia Huck Date: Tue, 2 Sep 2014 10:27:35 +0100 Subject: KVM: s390: register flic ops dynamically Using the new kvm_register_device_ops() interface makes us get rid of an #ifdef in common code. Cc: Gleb Natapov Cc: Paolo Bonzini Signed-off-by: Cornelia Huck Signed-off-by: Will Deacon Signed-off-by: Paolo Bonzini --- arch/s390/kvm/kvm-s390.c | 3 ++- arch/s390/kvm/kvm-s390.h | 1 + include/linux/kvm_host.h | 1 - virt/kvm/kvm_main.c | 4 ---- 4 files changed, 3 insertions(+), 6 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index b95d4a481b0c..56a411c0245a 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -122,7 +122,8 @@ void kvm_arch_hardware_unsetup(void) int kvm_arch_init(void *opaque) { - return 0; + /* Register floating interrupt controller interface. */ + return kvm_register_device_ops(&kvm_flic_ops, KVM_DEV_TYPE_FLIC); } /* Section: device related */ diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h index b1a77669137b..244d02303182 100644 --- a/arch/s390/kvm/kvm-s390.h +++ b/arch/s390/kvm/kvm-s390.h @@ -227,6 +227,7 @@ int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu); int psw_extint_disabled(struct kvm_vcpu *vcpu); void kvm_s390_destroy_adapters(struct kvm *kvm); int kvm_s390_si_ext_call_pending(struct kvm_vcpu *vcpu); +extern struct kvm_device_ops kvm_flic_ops; /* implemented in guestdbg.c */ void kvm_s390_backup_guest_per_regs(struct kvm_vcpu *vcpu); diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 601d321f96e7..7ef088bec715 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1069,7 +1069,6 @@ int kvm_register_device_ops(struct kvm_device_ops *ops, u32 type); extern struct kvm_device_ops kvm_mpic_ops; extern struct kvm_device_ops kvm_xics_ops; extern struct kvm_device_ops kvm_vfio_ops; -extern struct kvm_device_ops kvm_flic_ops; #ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 68d96f5dbfe2..f4e792fedb4f 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2285,10 +2285,6 @@ static struct kvm_device_ops *kvm_device_ops_table[KVM_DEV_TYPE_MAX] = { #ifdef CONFIG_KVM_VFIO [KVM_DEV_TYPE_VFIO] = &kvm_vfio_ops, #endif - -#ifdef CONFIG_S390 - [KVM_DEV_TYPE_FLIC] = &kvm_flic_ops, -#endif }; int kvm_register_device_ops(struct kvm_device_ops *ops, u32 type) -- cgit v1.2.3-58-ga151 From 80ce1639727e9d38729c34f162378508c307ca25 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Tue, 2 Sep 2014 10:27:36 +0100 Subject: KVM: VFIO: register kvm_device_ops dynamically Now that we have a dynamic means to register kvm_device_ops, use that for the VFIO kvm device, instead of relying on the static table. This is achieved by a module_init call to register the ops with KVM. Cc: Gleb Natapov Cc: Paolo Bonzini Acked-by: Alex Williamson Signed-off-by: Will Deacon Signed-off-by: Paolo Bonzini --- include/linux/kvm_host.h | 1 - virt/kvm/kvm_main.c | 4 ---- virt/kvm/vfio.c | 22 +++++++++++++++------- 3 files changed, 15 insertions(+), 12 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 7ef088bec715..d44a2d640551 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1068,7 +1068,6 @@ int kvm_register_device_ops(struct kvm_device_ops *ops, u32 type); extern struct kvm_device_ops kvm_mpic_ops; extern struct kvm_device_ops kvm_xics_ops; -extern struct kvm_device_ops kvm_vfio_ops; #ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index f4e792fedb4f..db57363cc287 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2281,10 +2281,6 @@ static struct kvm_device_ops *kvm_device_ops_table[KVM_DEV_TYPE_MAX] = { #ifdef CONFIG_KVM_XICS [KVM_DEV_TYPE_XICS] = &kvm_xics_ops, #endif - -#ifdef CONFIG_KVM_VFIO - [KVM_DEV_TYPE_VFIO] = &kvm_vfio_ops, -#endif }; int kvm_register_device_ops(struct kvm_device_ops *ops, u32 type) diff --git a/virt/kvm/vfio.c b/virt/kvm/vfio.c index ba1a93f935c7..bb11b36ee8a2 100644 --- a/virt/kvm/vfio.c +++ b/virt/kvm/vfio.c @@ -246,6 +246,16 @@ static void kvm_vfio_destroy(struct kvm_device *dev) kfree(dev); /* alloc by kvm_ioctl_create_device, free by .destroy */ } +static int kvm_vfio_create(struct kvm_device *dev, u32 type); + +static struct kvm_device_ops kvm_vfio_ops = { + .name = "kvm-vfio", + .create = kvm_vfio_create, + .destroy = kvm_vfio_destroy, + .set_attr = kvm_vfio_set_attr, + .has_attr = kvm_vfio_has_attr, +}; + static int kvm_vfio_create(struct kvm_device *dev, u32 type) { struct kvm_device *tmp; @@ -268,10 +278,8 @@ static int kvm_vfio_create(struct kvm_device *dev, u32 type) return 0; } -struct kvm_device_ops kvm_vfio_ops = { - .name = "kvm-vfio", - .create = kvm_vfio_create, - .destroy = kvm_vfio_destroy, - .set_attr = kvm_vfio_set_attr, - .has_attr = kvm_vfio_has_attr, -}; +static int __init kvm_vfio_ops_init(void) +{ + return kvm_register_device_ops(&kvm_vfio_ops, KVM_DEV_TYPE_VFIO); +} +module_init(kvm_vfio_ops_init); -- cgit v1.2.3-58-ga151 From 3c3c29fd0d7cddc32862c350d0700ce69953e3bd Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Wed, 24 Sep 2014 13:02:46 +0200 Subject: kvm-vfio: do not use module_init /me got confused between the kernel and QEMU. In the kernel, you can only have one module_init function, and it will prevent unloading the module unless you also have the corresponding module_exit function. So, commit 80ce1639727e (KVM: VFIO: register kvm_device_ops dynamically, 2014-09-02) broke unloading of the kvm module, by adding a module_init function and no module_exit. Repair it by making kvm_vfio_ops_init weak, and checking it in kvm_init. Cc: Will Deacon Cc: Gleb Natapov Cc: Alex Williamson Fixes: 80ce1639727e9d38729c34f162378508c307ca25 Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 4 ++++ virt/kvm/vfio.c | 4 ++-- virt/kvm/vfio.h | 13 +++++++++++++ 3 files changed, 19 insertions(+), 2 deletions(-) create mode 100644 virt/kvm/vfio.h (limited to 'virt/kvm/kvm_main.c') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index db57363cc287..499db0977f3c 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -57,6 +57,7 @@ #include "coalesced_mmio.h" #include "async_pf.h" +#include "vfio.h" #define CREATE_TRACE_POINTS #include @@ -3226,6 +3227,9 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align, goto out_undebugfs; } + r = kvm_vfio_ops_init(); + WARN_ON(r); + return 0; out_undebugfs: diff --git a/virt/kvm/vfio.c b/virt/kvm/vfio.c index bb11b36ee8a2..281e7cf2b8e5 100644 --- a/virt/kvm/vfio.c +++ b/virt/kvm/vfio.c @@ -18,6 +18,7 @@ #include #include #include +#include "vfio.h" struct kvm_vfio_group { struct list_head node; @@ -278,8 +279,7 @@ static int kvm_vfio_create(struct kvm_device *dev, u32 type) return 0; } -static int __init kvm_vfio_ops_init(void) +int kvm_vfio_ops_init(void) { return kvm_register_device_ops(&kvm_vfio_ops, KVM_DEV_TYPE_VFIO); } -module_init(kvm_vfio_ops_init); diff --git a/virt/kvm/vfio.h b/virt/kvm/vfio.h new file mode 100644 index 000000000000..92eac75d6b62 --- /dev/null +++ b/virt/kvm/vfio.h @@ -0,0 +1,13 @@ +#ifndef __KVM_VFIO_H +#define __KVM_VFIO_H + +#ifdef CONFIG_KVM_VFIO +int kvm_vfio_ops_init(void); +#else +static inline int kvm_vfio_ops_init(void) +{ + return 0; +} +#endif + +#endif -- cgit v1.2.3-58-ga151 From 234b239bea395316d7f78018c672f4a88b3cdf0d Mon Sep 17 00:00:00 2001 From: Andres Lagar-Cavilla Date: Wed, 17 Sep 2014 10:51:48 -0700 Subject: kvm: Faults which trigger IO release the mmap_sem MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When KVM handles a tdp fault it uses FOLL_NOWAIT. If the guest memory has been swapped out or is behind a filemap, this will trigger async readahead and return immediately. The rationale is that KVM will kick back the guest with an "async page fault" and allow for some other guest process to take over. If async PFs are enabled the fault is retried asap from an async workqueue. If not, it's retried immediately in the same code path. In either case the retry will not relinquish the mmap semaphore and will block on the IO. This is a bad thing, as other mmap semaphore users now stall as a function of swap or filemap latency. This patch ensures both the regular and async PF path re-enter the fault allowing for the mmap semaphore to be relinquished in the case of IO wait. Reviewed-by: Radim Krčmář Signed-off-by: Andres Lagar-Cavilla Acked-by: Andrew Morton Signed-off-by: Paolo Bonzini --- include/linux/kvm_host.h | 11 +++++++++++ include/linux/mm.h | 1 + mm/gup.c | 4 ++++ virt/kvm/async_pf.c | 4 +--- virt/kvm/kvm_main.c | 49 +++++++++++++++++++++++++++++++++++++++++++++--- 5 files changed, 63 insertions(+), 6 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index d44a2d640551..45aaeb3360c9 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -198,6 +198,17 @@ int kvm_setup_async_pf(struct kvm_vcpu *vcpu, gva_t gva, unsigned long hva, int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu); #endif +/* + * Carry out a gup that requires IO. Allow the mm to relinquish the mmap + * semaphore if the filemap/swap has to wait on a page lock. pagep == NULL + * controls whether we retry the gup one more time to completion in that case. + * Typically this is called after a FAULT_FLAG_RETRY_NOWAIT in the main tdp + * handler. + */ +int kvm_get_user_page_io(struct task_struct *tsk, struct mm_struct *mm, + unsigned long addr, bool write_fault, + struct page **pagep); + enum { OUTSIDE_GUEST_MODE, IN_GUEST_MODE, diff --git a/include/linux/mm.h b/include/linux/mm.h index 8981cc882ed2..0f4196a0bc20 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1985,6 +1985,7 @@ static inline struct page *follow_page(struct vm_area_struct *vma, #define FOLL_HWPOISON 0x100 /* check page is hwpoisoned */ #define FOLL_NUMA 0x200 /* force NUMA hinting page fault */ #define FOLL_MIGRATION 0x400 /* wait for page to replace migration entry */ +#define FOLL_TRIED 0x800 /* a retry, previous pass started an IO */ typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr, void *data); diff --git a/mm/gup.c b/mm/gup.c index 91d044b1600d..af7ea3e0826b 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -281,6 +281,10 @@ static int faultin_page(struct task_struct *tsk, struct vm_area_struct *vma, fault_flags |= FAULT_FLAG_ALLOW_RETRY; if (*flags & FOLL_NOWAIT) fault_flags |= FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_RETRY_NOWAIT; + if (*flags & FOLL_TRIED) { + VM_WARN_ON_ONCE(fault_flags & FAULT_FLAG_ALLOW_RETRY); + fault_flags |= FAULT_FLAG_TRIED; + } ret = handle_mm_fault(mm, vma, address, fault_flags); if (ret & VM_FAULT_ERROR) { diff --git a/virt/kvm/async_pf.c b/virt/kvm/async_pf.c index d6a3d0993d88..5ff7f7f2689a 100644 --- a/virt/kvm/async_pf.c +++ b/virt/kvm/async_pf.c @@ -80,9 +80,7 @@ static void async_pf_execute(struct work_struct *work) might_sleep(); - down_read(&mm->mmap_sem); - get_user_pages(NULL, mm, addr, 1, 1, 0, NULL, NULL); - up_read(&mm->mmap_sem); + kvm_get_user_page_io(NULL, mm, addr, 1, NULL); kvm_async_page_present_sync(vcpu, apf); spin_lock(&vcpu->async_pf.lock); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 499db0977f3c..1c6e8476b244 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1122,6 +1122,43 @@ static int get_user_page_nowait(struct task_struct *tsk, struct mm_struct *mm, return __get_user_pages(tsk, mm, start, 1, flags, page, NULL, NULL); } +int kvm_get_user_page_io(struct task_struct *tsk, struct mm_struct *mm, + unsigned long addr, bool write_fault, + struct page **pagep) +{ + int npages; + int locked = 1; + int flags = FOLL_TOUCH | FOLL_HWPOISON | + (pagep ? FOLL_GET : 0) | + (write_fault ? FOLL_WRITE : 0); + + /* + * If retrying the fault, we get here *not* having allowed the filemap + * to wait on the page lock. We should now allow waiting on the IO with + * the mmap semaphore released. + */ + down_read(&mm->mmap_sem); + npages = __get_user_pages(tsk, mm, addr, 1, flags, pagep, NULL, + &locked); + if (!locked) { + VM_BUG_ON(npages != -EBUSY); + + if (!pagep) + return 0; + + /* + * The previous call has now waited on the IO. Now we can + * retry and complete. Pass TRIED to ensure we do not re + * schedule async IO (see e.g. filemap_fault). + */ + down_read(&mm->mmap_sem); + npages = __get_user_pages(tsk, mm, addr, 1, flags | FOLL_TRIED, + pagep, NULL, NULL); + } + up_read(&mm->mmap_sem); + return npages; +} + static inline int check_user_page_hwpoison(unsigned long addr) { int rc, flags = FOLL_TOUCH | FOLL_HWPOISON | FOLL_WRITE; @@ -1184,9 +1221,15 @@ static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault, npages = get_user_page_nowait(current, current->mm, addr, write_fault, page); up_read(¤t->mm->mmap_sem); - } else - npages = get_user_pages_fast(addr, 1, write_fault, - page); + } else { + /* + * By now we have tried gup_fast, and possibly async_pf, and we + * are certainly not atomic. Time to retry the gup, allowing + * mmap semaphore to be relinquished in the case of IO. + */ + npages = kvm_get_user_page_io(current, current->mm, addr, + write_fault, page); + } if (npages != 1) return npages; -- cgit v1.2.3-58-ga151 From 2ea75be3219571d0ec009ce20d9971e54af96e09 Mon Sep 17 00:00:00 2001 From: David Matlack Date: Fri, 19 Sep 2014 16:03:25 -0700 Subject: kvm: don't take vcpu mutex for obviously invalid vcpu ioctls vcpu ioctls can hang the calling thread if issued while a vcpu is running. However, invalid ioctls can happen when userspace tries to probe the kind of file descriptors (e.g. isatty() calls ioctl(TCGETS)); in that case, we know the ioctl is going to be rejected as invalid anyway and we can fail before trying to take the vcpu mutex. This patch does not change functionality, it just makes invalid ioctls fail faster. Cc: stable@vger.kernel.org Signed-off-by: David Matlack Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'virt/kvm/kvm_main.c') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 1c6e8476b244..ff42b11d2b9c 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -52,6 +52,7 @@ #include #include +#include #include #include @@ -2032,6 +2033,9 @@ static long kvm_vcpu_ioctl(struct file *filp, if (vcpu->kvm->mm != current->mm) return -EIO; + if (unlikely(_IOC_TYPE(ioctl) != KVMIO)) + return -EINVAL; + #if defined(CONFIG_S390) || defined(CONFIG_PPC) || defined(CONFIG_MIPS) /* * Special cases: vcpu ioctls that are asynchronous to vcpu execution, -- cgit v1.2.3-58-ga151 From 57128468080a8b6ea452223036d3e417f748af55 Mon Sep 17 00:00:00 2001 From: Andres Lagar-Cavilla Date: Mon, 22 Sep 2014 14:54:42 -0700 Subject: kvm: Fix page ageing bugs 1. We were calling clear_flush_young_notify in unmap_one, but we are within an mmu notifier invalidate range scope. The spte exists no more (due to range_start) and the accessed bit info has already been propagated (due to kvm_pfn_set_accessed). Simply call clear_flush_young. 2. We clear_flush_young on a primary MMU PMD, but this may be mapped as a collection of PTEs by the secondary MMU (e.g. during log-dirty). This required expanding the interface of the clear_flush_young mmu notifier, so a lot of code has been trivially touched. 3. In the absence of shadow_accessed_mask (e.g. EPT A bit), we emulate the access bit by blowing the spte. This requires proper synchronizing with MMU notifier consumers, like every other removal of spte's does. Signed-off-by: Andres Lagar-Cavilla Acked-by: Rik van Riel Signed-off-by: Paolo Bonzini --- arch/arm/include/asm/kvm_host.h | 3 ++- arch/arm64/include/asm/kvm_host.h | 3 ++- arch/powerpc/include/asm/kvm_host.h | 2 +- arch/powerpc/include/asm/kvm_ppc.h | 2 +- arch/powerpc/kvm/book3s.c | 4 ++-- arch/powerpc/kvm/book3s.h | 3 ++- arch/powerpc/kvm/book3s_64_mmu_hv.c | 4 ++-- arch/powerpc/kvm/book3s_pr.c | 3 ++- arch/powerpc/kvm/e500_mmu_host.c | 2 +- arch/x86/include/asm/kvm_host.h | 2 +- arch/x86/kvm/mmu.c | 38 ++++++++++++++++++++++--------------- drivers/iommu/amd_iommu_v2.c | 6 ++++-- include/linux/mmu_notifier.h | 24 ++++++++++++++++------- mm/mmu_notifier.c | 5 +++-- mm/rmap.c | 6 +++++- virt/kvm/kvm_main.c | 5 +++-- 16 files changed, 71 insertions(+), 41 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 032a8538318a..8c3f7eb62b54 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -170,7 +170,8 @@ unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu); int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices); /* We do not have shadow page tables, hence the empty hooks */ -static inline int kvm_age_hva(struct kvm *kvm, unsigned long hva) +static inline int kvm_age_hva(struct kvm *kvm, unsigned long start, + unsigned long end) { return 0; } diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index be9970a59497..a3c671b3acc9 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -180,7 +180,8 @@ int kvm_unmap_hva_range(struct kvm *kvm, void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte); /* We do not have shadow page tables, hence the empty hooks */ -static inline int kvm_age_hva(struct kvm *kvm, unsigned long hva) +static inline int kvm_age_hva(struct kvm *kvm, unsigned long start, + unsigned long end) { return 0; } diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 604000882352..d329bc5543a2 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -56,7 +56,7 @@ extern int kvm_unmap_hva(struct kvm *kvm, unsigned long hva); extern int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end); -extern int kvm_age_hva(struct kvm *kvm, unsigned long hva); +extern int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end); extern int kvm_test_age_hva(struct kvm *kvm, unsigned long hva); extern void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte); diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index fb86a2299d8a..d4a92d7cea6a 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -243,7 +243,7 @@ struct kvmppc_ops { int (*unmap_hva)(struct kvm *kvm, unsigned long hva); int (*unmap_hva_range)(struct kvm *kvm, unsigned long start, unsigned long end); - int (*age_hva)(struct kvm *kvm, unsigned long hva); + int (*age_hva)(struct kvm *kvm, unsigned long start, unsigned long end); int (*test_age_hva)(struct kvm *kvm, unsigned long hva); void (*set_spte_hva)(struct kvm *kvm, unsigned long hva, pte_t pte); void (*mmu_destroy)(struct kvm_vcpu *vcpu); diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c index dd03f6b299ba..c16cfbfeb781 100644 --- a/arch/powerpc/kvm/book3s.c +++ b/arch/powerpc/kvm/book3s.c @@ -851,9 +851,9 @@ int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end) return kvm->arch.kvm_ops->unmap_hva_range(kvm, start, end); } -int kvm_age_hva(struct kvm *kvm, unsigned long hva) +int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end) { - return kvm->arch.kvm_ops->age_hva(kvm, hva); + return kvm->arch.kvm_ops->age_hva(kvm, start, end); } int kvm_test_age_hva(struct kvm *kvm, unsigned long hva) diff --git a/arch/powerpc/kvm/book3s.h b/arch/powerpc/kvm/book3s.h index 4bf956cf94d6..d2b3ec088b8c 100644 --- a/arch/powerpc/kvm/book3s.h +++ b/arch/powerpc/kvm/book3s.h @@ -17,7 +17,8 @@ extern void kvmppc_core_flush_memslot_hv(struct kvm *kvm, extern int kvm_unmap_hva_hv(struct kvm *kvm, unsigned long hva); extern int kvm_unmap_hva_range_hv(struct kvm *kvm, unsigned long start, unsigned long end); -extern int kvm_age_hva_hv(struct kvm *kvm, unsigned long hva); +extern int kvm_age_hva_hv(struct kvm *kvm, unsigned long start, + unsigned long end); extern int kvm_test_age_hva_hv(struct kvm *kvm, unsigned long hva); extern void kvm_set_spte_hva_hv(struct kvm *kvm, unsigned long hva, pte_t pte); diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index 72c20bb16d26..81460c5359c0 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -1002,11 +1002,11 @@ static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp, return ret; } -int kvm_age_hva_hv(struct kvm *kvm, unsigned long hva) +int kvm_age_hva_hv(struct kvm *kvm, unsigned long start, unsigned long end) { if (!kvm->arch.using_mmu_notifiers) return 0; - return kvm_handle_hva(kvm, hva, kvm_age_rmapp); + return kvm_handle_hva_range(kvm, start, end, kvm_age_rmapp); } static int kvm_test_age_rmapp(struct kvm *kvm, unsigned long *rmapp, diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index faffb27badd9..852fcd8951c4 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -295,7 +295,8 @@ static int kvm_unmap_hva_range_pr(struct kvm *kvm, unsigned long start, return 0; } -static int kvm_age_hva_pr(struct kvm *kvm, unsigned long hva) +static int kvm_age_hva_pr(struct kvm *kvm, unsigned long start, + unsigned long end) { /* XXX could be more clever ;) */ return 0; diff --git a/arch/powerpc/kvm/e500_mmu_host.c b/arch/powerpc/kvm/e500_mmu_host.c index 08f14bb57897..b1f3f630315e 100644 --- a/arch/powerpc/kvm/e500_mmu_host.c +++ b/arch/powerpc/kvm/e500_mmu_host.c @@ -732,7 +732,7 @@ int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end) return 0; } -int kvm_age_hva(struct kvm *kvm, unsigned long hva) +int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end) { /* XXX could be more clever ;) */ return 0; diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index eeeb573fcf6f..763d273cab1d 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1035,7 +1035,7 @@ asmlinkage void kvm_spurious_fault(void); #define KVM_ARCH_WANT_MMU_NOTIFIER int kvm_unmap_hva(struct kvm *kvm, unsigned long hva); int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end); -int kvm_age_hva(struct kvm *kvm, unsigned long hva); +int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end); int kvm_test_age_hva(struct kvm *kvm, unsigned long hva); void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte); int cpuid_maxphyaddr(struct kvm_vcpu *vcpu); diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 47d534066325..3201e93ebd07 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1417,18 +1417,7 @@ static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp, struct rmap_iterator uninitialized_var(iter); int young = 0; - /* - * In case of absence of EPT Access and Dirty Bits supports, - * emulate the accessed bit for EPT, by checking if this page has - * an EPT mapping, and clearing it if it does. On the next access, - * a new EPT mapping will be established. - * This has some overhead, but not as much as the cost of swapping - * out actively used pages or breaking up actively used hugepages. - */ - if (!shadow_accessed_mask) { - young = kvm_unmap_rmapp(kvm, rmapp, slot, gfn, level, data); - goto out; - } + BUG_ON(!shadow_accessed_mask); for (sptep = rmap_get_first(*rmapp, &iter); sptep; sptep = rmap_get_next(&iter)) { @@ -1440,7 +1429,6 @@ static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp, (unsigned long *)sptep); } } -out: trace_kvm_age_page(gfn, level, slot, young); return young; } @@ -1489,9 +1477,29 @@ static void rmap_recycle(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn) kvm_flush_remote_tlbs(vcpu->kvm); } -int kvm_age_hva(struct kvm *kvm, unsigned long hva) +int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end) { - return kvm_handle_hva(kvm, hva, 0, kvm_age_rmapp); + /* + * In case of absence of EPT Access and Dirty Bits supports, + * emulate the accessed bit for EPT, by checking if this page has + * an EPT mapping, and clearing it if it does. On the next access, + * a new EPT mapping will be established. + * This has some overhead, but not as much as the cost of swapping + * out actively used pages or breaking up actively used hugepages. + */ + if (!shadow_accessed_mask) { + /* + * We are holding the kvm->mmu_lock, and we are blowing up + * shadow PTEs. MMU notifier consumers need to be kept at bay. + * This is correct as long as we don't decouple the mmu_lock + * protected regions (like invalidate_range_start|end does). + */ + kvm->mmu_notifier_seq++; + return kvm_handle_hva_range(kvm, start, end, 0, + kvm_unmap_rmapp); + } + + return kvm_handle_hva_range(kvm, start, end, 0, kvm_age_rmapp); } int kvm_test_age_hva(struct kvm *kvm, unsigned long hva) diff --git a/drivers/iommu/amd_iommu_v2.c b/drivers/iommu/amd_iommu_v2.c index 5f578e850fc5..90d734bbf467 100644 --- a/drivers/iommu/amd_iommu_v2.c +++ b/drivers/iommu/amd_iommu_v2.c @@ -402,9 +402,11 @@ static void __mn_flush_page(struct mmu_notifier *mn, static int mn_clear_flush_young(struct mmu_notifier *mn, struct mm_struct *mm, - unsigned long address) + unsigned long start, + unsigned long end) { - __mn_flush_page(mn, address); + for (; start < end; start += PAGE_SIZE) + __mn_flush_page(mn, start); return 0; } diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h index 27288692241e..88787bb4b3b9 100644 --- a/include/linux/mmu_notifier.h +++ b/include/linux/mmu_notifier.h @@ -57,10 +57,13 @@ struct mmu_notifier_ops { * pte. This way the VM will provide proper aging to the * accesses to the page through the secondary MMUs and not * only to the ones through the Linux pte. + * Start-end is necessary in case the secondary MMU is mapping the page + * at a smaller granularity than the primary MMU. */ int (*clear_flush_young)(struct mmu_notifier *mn, struct mm_struct *mm, - unsigned long address); + unsigned long start, + unsigned long end); /* * test_young is called to check the young/accessed bitflag in @@ -175,7 +178,8 @@ extern void mmu_notifier_unregister_no_release(struct mmu_notifier *mn, extern void __mmu_notifier_mm_destroy(struct mm_struct *mm); extern void __mmu_notifier_release(struct mm_struct *mm); extern int __mmu_notifier_clear_flush_young(struct mm_struct *mm, - unsigned long address); + unsigned long start, + unsigned long end); extern int __mmu_notifier_test_young(struct mm_struct *mm, unsigned long address); extern void __mmu_notifier_change_pte(struct mm_struct *mm, @@ -194,10 +198,11 @@ static inline void mmu_notifier_release(struct mm_struct *mm) } static inline int mmu_notifier_clear_flush_young(struct mm_struct *mm, - unsigned long address) + unsigned long start, + unsigned long end) { if (mm_has_notifiers(mm)) - return __mmu_notifier_clear_flush_young(mm, address); + return __mmu_notifier_clear_flush_young(mm, start, end); return 0; } @@ -255,7 +260,9 @@ static inline void mmu_notifier_mm_destroy(struct mm_struct *mm) unsigned long ___address = __address; \ __young = ptep_clear_flush_young(___vma, ___address, __ptep); \ __young |= mmu_notifier_clear_flush_young(___vma->vm_mm, \ - ___address); \ + ___address, \ + ___address + \ + PAGE_SIZE); \ __young; \ }) @@ -266,7 +273,9 @@ static inline void mmu_notifier_mm_destroy(struct mm_struct *mm) unsigned long ___address = __address; \ __young = pmdp_clear_flush_young(___vma, ___address, __pmdp); \ __young |= mmu_notifier_clear_flush_young(___vma->vm_mm, \ - ___address); \ + ___address, \ + ___address + \ + PMD_SIZE); \ __young; \ }) @@ -301,7 +310,8 @@ static inline void mmu_notifier_release(struct mm_struct *mm) } static inline int mmu_notifier_clear_flush_young(struct mm_struct *mm, - unsigned long address) + unsigned long start, + unsigned long end) { return 0; } diff --git a/mm/mmu_notifier.c b/mm/mmu_notifier.c index 950813b1eb36..2c8da9825fe3 100644 --- a/mm/mmu_notifier.c +++ b/mm/mmu_notifier.c @@ -107,7 +107,8 @@ void __mmu_notifier_release(struct mm_struct *mm) * existed or not. */ int __mmu_notifier_clear_flush_young(struct mm_struct *mm, - unsigned long address) + unsigned long start, + unsigned long end) { struct mmu_notifier *mn; int young = 0, id; @@ -115,7 +116,7 @@ int __mmu_notifier_clear_flush_young(struct mm_struct *mm, id = srcu_read_lock(&srcu); hlist_for_each_entry_rcu(mn, &mm->mmu_notifier_mm->list, hlist) { if (mn->ops->clear_flush_young) - young |= mn->ops->clear_flush_young(mn, mm, address); + young |= mn->ops->clear_flush_young(mn, mm, start, end); } srcu_read_unlock(&srcu, id); diff --git a/mm/rmap.c b/mm/rmap.c index 3e8491c504f8..bc74e0012809 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1355,7 +1355,11 @@ static int try_to_unmap_cluster(unsigned long cursor, unsigned int *mapcount, continue; /* don't unmap */ } - if (ptep_clear_flush_young_notify(vma, address, pte)) + /* + * No need for _notify because we're within an + * mmu_notifier_invalidate_range_ {start|end} scope. + */ + if (ptep_clear_flush_young(vma, address, pte)) continue; /* Nuke the page table entry. */ diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index ff42b11d2b9c..0316314d48f4 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -369,7 +369,8 @@ static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn, static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn, struct mm_struct *mm, - unsigned long address) + unsigned long start, + unsigned long end) { struct kvm *kvm = mmu_notifier_to_kvm(mn); int young, idx; @@ -377,7 +378,7 @@ static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn, idx = srcu_read_lock(&kvm->srcu); spin_lock(&kvm->mmu_lock); - young = kvm_age_hva(kvm, address); + young = kvm_age_hva(kvm, start, end); if (young) kvm_flush_remote_tlbs(kvm); -- cgit v1.2.3-58-ga151 From 445b8236959bfe624a5aa9bce89f44a3bec9b2b1 Mon Sep 17 00:00:00 2001 From: Tang Chen Date: Wed, 24 Sep 2014 15:57:55 +0800 Subject: kvm: Rename make_all_cpus_request() to kvm_make_all_cpus_request() and make it non-static Different architectures need different requests, and in fact we will use this function in architecture-specific code later. This will be outside kvm_main.c, so make it non-static and rename it to kvm_make_all_cpus_request(). Reviewed-by: Paolo Bonzini Signed-off-by: Tang Chen Signed-off-by: Paolo Bonzini --- include/linux/kvm_host.h | 1 + virt/kvm/kvm_main.c | 10 +++++----- 2 files changed, 6 insertions(+), 5 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 45aaeb3360c9..12c591fc2571 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -586,6 +586,7 @@ void kvm_flush_remote_tlbs(struct kvm *kvm); void kvm_reload_remote_mmus(struct kvm *kvm); void kvm_make_mclock_inprogress_request(struct kvm *kvm); void kvm_make_scan_ioapic_request(struct kvm *kvm); +bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req); long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 0316314d48f4..5b8ca365932a 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -153,7 +153,7 @@ static void ack_flush(void *_completed) { } -static bool make_all_cpus_request(struct kvm *kvm, unsigned int req) +bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req) { int i, cpu, me; cpumask_var_t cpus; @@ -190,7 +190,7 @@ void kvm_flush_remote_tlbs(struct kvm *kvm) long dirty_count = kvm->tlbs_dirty; smp_mb(); - if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH)) + if (kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH)) ++kvm->stat.remote_tlb_flush; cmpxchg(&kvm->tlbs_dirty, dirty_count, 0); } @@ -198,17 +198,17 @@ EXPORT_SYMBOL_GPL(kvm_flush_remote_tlbs); void kvm_reload_remote_mmus(struct kvm *kvm) { - make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD); + kvm_make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD); } void kvm_make_mclock_inprogress_request(struct kvm *kvm) { - make_all_cpus_request(kvm, KVM_REQ_MCLOCK_INPROGRESS); + kvm_make_all_cpus_request(kvm, KVM_REQ_MCLOCK_INPROGRESS); } void kvm_make_scan_ioapic_request(struct kvm *kvm) { - make_all_cpus_request(kvm, KVM_REQ_SCAN_IOAPIC); + kvm_make_all_cpus_request(kvm, KVM_REQ_SCAN_IOAPIC); } int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id) -- cgit v1.2.3-58-ga151 From fe71557afbec641fee73711e40602bed37f6f33b Mon Sep 17 00:00:00 2001 From: Tang Chen Date: Wed, 24 Sep 2014 15:57:57 +0800 Subject: kvm: Add arch specific mmu notifier for page invalidation This will be used to let the guest run while the APIC access page is not pinned. Because subsequent patches will fill in the function for x86, place the (still empty) x86 implementation in the x86.c file instead of adding an inline function in kvm_host.h. Signed-off-by: Tang Chen Signed-off-by: Paolo Bonzini --- arch/arm/include/asm/kvm_host.h | 5 +++++ arch/arm64/include/asm/kvm_host.h | 5 +++++ arch/powerpc/include/asm/kvm_host.h | 5 +++++ arch/x86/include/asm/kvm_host.h | 2 ++ arch/x86/kvm/x86.c | 5 +++++ virt/kvm/kvm_main.c | 3 +++ 6 files changed, 25 insertions(+) (limited to 'virt/kvm/kvm_main.c') diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 8c3f7eb62b54..155497c2b4da 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -181,6 +181,11 @@ static inline int kvm_test_age_hva(struct kvm *kvm, unsigned long hva) return 0; } +static inline void kvm_arch_mmu_notifier_invalidate_page(struct kvm *kvm, + unsigned long address) +{ +} + struct kvm_vcpu *kvm_arm_get_running_vcpu(void); struct kvm_vcpu __percpu **kvm_get_running_vcpus(void); diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index a3c671b3acc9..992d9da88119 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -191,6 +191,11 @@ static inline int kvm_test_age_hva(struct kvm *kvm, unsigned long hva) return 0; } +static inline void kvm_arch_mmu_notifier_invalidate_page(struct kvm *kvm, + unsigned long address) +{ +} + struct kvm_vcpu *kvm_arm_get_running_vcpu(void); struct kvm_vcpu __percpu **kvm_get_running_vcpus(void); diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index d329bc5543a2..2cf6c1587d43 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -60,6 +60,11 @@ extern int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end); extern int kvm_test_age_hva(struct kvm *kvm, unsigned long hva); extern void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte); +static inline void kvm_arch_mmu_notifier_invalidate_page(struct kvm *kvm, + unsigned long address) +{ +} + #define HPTEG_CACHE_NUM (1 << 15) #define HPTEG_HASH_BITS_PTE 13 #define HPTEG_HASH_BITS_PTE_LONG 12 diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 763d273cab1d..022c356e0fed 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1044,6 +1044,8 @@ int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu); int kvm_arch_interrupt_allowed(struct kvm_vcpu *vcpu); int kvm_cpu_get_interrupt(struct kvm_vcpu *v); void kvm_vcpu_reset(struct kvm_vcpu *vcpu); +void kvm_arch_mmu_notifier_invalidate_page(struct kvm *kvm, + unsigned long address); void kvm_define_shared_msr(unsigned index, u32 msr); void kvm_set_shared_msr(unsigned index, u64 val, u64 mask); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 6152aa0da7dd..142569e6f8f9 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6026,6 +6026,11 @@ static void kvm_vcpu_flush_tlb(struct kvm_vcpu *vcpu) kvm_x86_ops->tlb_flush(vcpu); } +void kvm_arch_mmu_notifier_invalidate_page(struct kvm *kvm, + unsigned long address) +{ +} + /* * Returns 1 to let __vcpu_run() continue the guest execution loop without * exiting to the userspace. Otherwise, the value will be returned to the diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 5b8ca365932a..3f16f569169e 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -296,6 +296,9 @@ static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn, kvm_flush_remote_tlbs(kvm); spin_unlock(&kvm->mmu_lock); + + kvm_arch_mmu_notifier_invalidate_page(kvm, address); + srcu_read_unlock(&kvm->srcu, idx); } -- cgit v1.2.3-58-ga151 From bb0ca6acd466af55c95b7ce508f29e23a24cabd9 Mon Sep 17 00:00:00 2001 From: Andres Lagar-Cavilla Date: Thu, 25 Sep 2014 15:26:50 -0700 Subject: kvm: Fix kvm_get_page_retry_io __gup retval check Confusion around -EBUSY and zero (inside a BUG_ON no less). Reported-by: Andrea Arcangeli Signed-off-by: Andres Lagar-Cavilla Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 3f16f569169e..a1cf53ee0d28 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1146,7 +1146,7 @@ int kvm_get_user_page_io(struct task_struct *tsk, struct mm_struct *mm, npages = __get_user_pages(tsk, mm, addr, 1, flags, pagep, NULL, &locked); if (!locked) { - VM_BUG_ON(npages != -EBUSY); + VM_BUG_ON(npages); if (!pagep) return 0; -- cgit v1.2.3-58-ga151