diff options
| -rw-r--r-- | arch/arm64/include/asm/kvm_host.h | 3 | ||||
| -rw-r--r-- | arch/arm64/kvm/arch_timer.c | 4 | ||||
| -rw-r--r-- | arch/arm64/kvm/arm.c | 43 | ||||
| -rw-r--r-- | arch/arm64/kvm/vgic/vgic-init.c | 4 | ||||
| -rw-r--r-- | arch/arm64/kvm/vgic/vgic-its.c | 8 | ||||
| -rw-r--r-- | arch/arm64/kvm/vgic/vgic-kvm-device.c | 12 | ||||
| -rw-r--r-- | arch/riscv/kvm/aia_device.c | 34 | ||||
| -rw-r--r-- | arch/x86/kvm/svm/sev.c | 72 | ||||
| -rw-r--r-- | include/linux/kvm_host.h | 4 | ||||
| -rw-r--r-- | include/linux/mutex.h | 32 | ||||
| -rw-r--r-- | kernel/locking/mutex.c | 21 | ||||
| -rw-r--r-- | rust/helpers/mutex.c | 5 | ||||
| -rw-r--r-- | virt/kvm/kvm_main.c | 59 |
13 files changed, 131 insertions, 170 deletions
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index d941abc6b5ee..6ce2c5173482 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -1320,9 +1320,6 @@ int __init populate_sysreg_config(const struct sys_reg_desc *sr, unsigned int idx); int __init populate_nv_trap_config(void); -bool lock_all_vcpus(struct kvm *kvm); -void unlock_all_vcpus(struct kvm *kvm); - void kvm_calculate_traps(struct kvm_vcpu *vcpu); /* MMIO helpers */ diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c index 5133dcbfe9f7..fdbc8beec930 100644 --- a/arch/arm64/kvm/arch_timer.c +++ b/arch/arm64/kvm/arch_timer.c @@ -1766,7 +1766,7 @@ int kvm_vm_ioctl_set_counter_offset(struct kvm *kvm, mutex_lock(&kvm->lock); - if (lock_all_vcpus(kvm)) { + if (!kvm_trylock_all_vcpus(kvm)) { set_bit(KVM_ARCH_FLAG_VM_COUNTER_OFFSET, &kvm->arch.flags); /* @@ -1778,7 +1778,7 @@ int kvm_vm_ioctl_set_counter_offset(struct kvm *kvm, kvm->arch.timer_data.voffset = offset->counter_offset; kvm->arch.timer_data.poffset = offset->counter_offset; - unlock_all_vcpus(kvm); + kvm_unlock_all_vcpus(kvm); } else { ret = -EBUSY; } diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 36cfcffb40d8..248e257e988b 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1924,49 +1924,6 @@ int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) } } -/* unlocks vcpus from @vcpu_lock_idx and smaller */ -static void unlock_vcpus(struct kvm *kvm, int vcpu_lock_idx) -{ - struct kvm_vcpu *tmp_vcpu; - - for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) { - tmp_vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx); - mutex_unlock(&tmp_vcpu->mutex); - } -} - -void unlock_all_vcpus(struct kvm *kvm) -{ - lockdep_assert_held(&kvm->lock); - - unlock_vcpus(kvm, atomic_read(&kvm->online_vcpus) - 1); -} - -/* Returns true if all vcpus were locked, false otherwise */ -bool lock_all_vcpus(struct kvm *kvm) -{ - struct kvm_vcpu *tmp_vcpu; - unsigned long c; - - lockdep_assert_held(&kvm->lock); - - /* - * Any time a vcpu is in an ioctl (including running), the - * core KVM code tries to grab the vcpu->mutex. - * - * By grabbing the vcpu->mutex of all VCPUs we ensure that no - * other VCPUs can fiddle with the state while we access it. - */ - kvm_for_each_vcpu(c, tmp_vcpu, kvm) { - if (!mutex_trylock(&tmp_vcpu->mutex)) { - unlock_vcpus(kvm, c - 1); - return false; - } - } - - return true; -} - static unsigned long nvhe_percpu_size(void) { return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) - diff --git a/arch/arm64/kvm/vgic/vgic-init.c b/arch/arm64/kvm/vgic/vgic-init.c index 1f33e71c2a73..6a426d403a6b 100644 --- a/arch/arm64/kvm/vgic/vgic-init.c +++ b/arch/arm64/kvm/vgic/vgic-init.c @@ -88,7 +88,7 @@ int kvm_vgic_create(struct kvm *kvm, u32 type) lockdep_assert_held(&kvm->lock); ret = -EBUSY; - if (!lock_all_vcpus(kvm)) + if (kvm_trylock_all_vcpus(kvm)) return ret; mutex_lock(&kvm->arch.config_lock); @@ -142,7 +142,7 @@ int kvm_vgic_create(struct kvm *kvm, u32 type) out_unlock: mutex_unlock(&kvm->arch.config_lock); - unlock_all_vcpus(kvm); + kvm_unlock_all_vcpus(kvm); return ret; } diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c index 569f9da9049f..2eb3e023f66a 100644 --- a/arch/arm64/kvm/vgic/vgic-its.c +++ b/arch/arm64/kvm/vgic/vgic-its.c @@ -1971,7 +1971,7 @@ static int vgic_its_attr_regs_access(struct kvm_device *dev, mutex_lock(&dev->kvm->lock); - if (!lock_all_vcpus(dev->kvm)) { + if (kvm_trylock_all_vcpus(dev->kvm)) { mutex_unlock(&dev->kvm->lock); return -EBUSY; } @@ -2006,7 +2006,7 @@ static int vgic_its_attr_regs_access(struct kvm_device *dev, } out: mutex_unlock(&dev->kvm->arch.config_lock); - unlock_all_vcpus(dev->kvm); + kvm_unlock_all_vcpus(dev->kvm); mutex_unlock(&dev->kvm->lock); return ret; } @@ -2676,7 +2676,7 @@ static int vgic_its_ctrl(struct kvm *kvm, struct vgic_its *its, u64 attr) mutex_lock(&kvm->lock); - if (!lock_all_vcpus(kvm)) { + if (kvm_trylock_all_vcpus(kvm)) { mutex_unlock(&kvm->lock); return -EBUSY; } @@ -2698,7 +2698,7 @@ static int vgic_its_ctrl(struct kvm *kvm, struct vgic_its *its, u64 attr) mutex_unlock(&its->its_lock); mutex_unlock(&kvm->arch.config_lock); - unlock_all_vcpus(kvm); + kvm_unlock_all_vcpus(kvm); mutex_unlock(&kvm->lock); return ret; } diff --git a/arch/arm64/kvm/vgic/vgic-kvm-device.c b/arch/arm64/kvm/vgic/vgic-kvm-device.c index 359094f68c23..f9ae790163fb 100644 --- a/arch/arm64/kvm/vgic/vgic-kvm-device.c +++ b/arch/arm64/kvm/vgic/vgic-kvm-device.c @@ -268,7 +268,7 @@ static int vgic_set_common_attr(struct kvm_device *dev, return -ENXIO; mutex_lock(&dev->kvm->lock); - if (!lock_all_vcpus(dev->kvm)) { + if (kvm_trylock_all_vcpus(dev->kvm)) { mutex_unlock(&dev->kvm->lock); return -EBUSY; } @@ -276,7 +276,7 @@ static int vgic_set_common_attr(struct kvm_device *dev, mutex_lock(&dev->kvm->arch.config_lock); r = vgic_v3_save_pending_tables(dev->kvm); mutex_unlock(&dev->kvm->arch.config_lock); - unlock_all_vcpus(dev->kvm); + kvm_unlock_all_vcpus(dev->kvm); mutex_unlock(&dev->kvm->lock); return r; } @@ -390,7 +390,7 @@ static int vgic_v2_attr_regs_access(struct kvm_device *dev, mutex_lock(&dev->kvm->lock); - if (!lock_all_vcpus(dev->kvm)) { + if (kvm_trylock_all_vcpus(dev->kvm)) { mutex_unlock(&dev->kvm->lock); return -EBUSY; } @@ -415,7 +415,7 @@ static int vgic_v2_attr_regs_access(struct kvm_device *dev, out: mutex_unlock(&dev->kvm->arch.config_lock); - unlock_all_vcpus(dev->kvm); + kvm_unlock_all_vcpus(dev->kvm); mutex_unlock(&dev->kvm->lock); if (!ret && !is_write) @@ -554,7 +554,7 @@ static int vgic_v3_attr_regs_access(struct kvm_device *dev, mutex_lock(&dev->kvm->lock); - if (!lock_all_vcpus(dev->kvm)) { + if (kvm_trylock_all_vcpus(dev->kvm)) { mutex_unlock(&dev->kvm->lock); return -EBUSY; } @@ -611,7 +611,7 @@ static int vgic_v3_attr_regs_access(struct kvm_device *dev, out: mutex_unlock(&dev->kvm->arch.config_lock); - unlock_all_vcpus(dev->kvm); + kvm_unlock_all_vcpus(dev->kvm); mutex_unlock(&dev->kvm->lock); if (!ret && uaccess && !is_write) { diff --git a/arch/riscv/kvm/aia_device.c b/arch/riscv/kvm/aia_device.c index 43e472ff3e1a..806c41931cde 100644 --- a/arch/riscv/kvm/aia_device.c +++ b/arch/riscv/kvm/aia_device.c @@ -12,36 +12,6 @@ #include <linux/kvm_host.h> #include <linux/uaccess.h> -static void unlock_vcpus(struct kvm *kvm, int vcpu_lock_idx) -{ - struct kvm_vcpu *tmp_vcpu; - - for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) { - tmp_vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx); - mutex_unlock(&tmp_vcpu->mutex); - } -} - -static void unlock_all_vcpus(struct kvm *kvm) -{ - unlock_vcpus(kvm, atomic_read(&kvm->online_vcpus) - 1); -} - -static bool lock_all_vcpus(struct kvm *kvm) -{ - struct kvm_vcpu *tmp_vcpu; - unsigned long c; - - kvm_for_each_vcpu(c, tmp_vcpu, kvm) { - if (!mutex_trylock(&tmp_vcpu->mutex)) { - unlock_vcpus(kvm, c - 1); - return false; - } - } - - return true; -} - static int aia_create(struct kvm_device *dev, u32 type) { int ret; @@ -53,7 +23,7 @@ static int aia_create(struct kvm_device *dev, u32 type) return -EEXIST; ret = -EBUSY; - if (!lock_all_vcpus(kvm)) + if (kvm_trylock_all_vcpus(kvm)) return ret; kvm_for_each_vcpu(i, vcpu, kvm) { @@ -65,7 +35,7 @@ static int aia_create(struct kvm_device *dev, u32 type) kvm->arch.aia.in_kernel = true; out_unlock: - unlock_all_vcpus(kvm); + kvm_unlock_all_vcpus(kvm); return ret; } diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 978a0088a3f1..6c2f840a0171 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -1884,70 +1884,6 @@ static void sev_unlock_two_vms(struct kvm *dst_kvm, struct kvm *src_kvm) atomic_set_release(&src_sev->migration_in_progress, 0); } -/* vCPU mutex subclasses. */ -enum sev_migration_role { - SEV_MIGRATION_SOURCE = 0, - SEV_MIGRATION_TARGET, - SEV_NR_MIGRATION_ROLES, -}; - -static int sev_lock_vcpus_for_migration(struct kvm *kvm, - enum sev_migration_role role) -{ - struct kvm_vcpu *vcpu; - unsigned long i, j; - - kvm_for_each_vcpu(i, vcpu, kvm) { - if (mutex_lock_killable_nested(&vcpu->mutex, role)) - goto out_unlock; - -#ifdef CONFIG_PROVE_LOCKING - if (!i) - /* - * Reset the role to one that avoids colliding with - * the role used for the first vcpu mutex. - */ - role = SEV_NR_MIGRATION_ROLES; - else - mutex_release(&vcpu->mutex.dep_map, _THIS_IP_); -#endif - } - - return 0; - -out_unlock: - - kvm_for_each_vcpu(j, vcpu, kvm) { - if (i == j) - break; - -#ifdef CONFIG_PROVE_LOCKING - if (j) - mutex_acquire(&vcpu->mutex.dep_map, role, 0, _THIS_IP_); -#endif - - mutex_unlock(&vcpu->mutex); - } - return -EINTR; -} - -static void sev_unlock_vcpus_for_migration(struct kvm *kvm) -{ - struct kvm_vcpu *vcpu; - unsigned long i; - bool first = true; - - kvm_for_each_vcpu(i, vcpu, kvm) { - if (first) - first = false; - else - mutex_acquire(&vcpu->mutex.dep_map, - SEV_NR_MIGRATION_ROLES, 0, _THIS_IP_); - - mutex_unlock(&vcpu->mutex); - } -} - static void sev_migrate_from(struct kvm *dst_kvm, struct kvm *src_kvm) { struct kvm_sev_info *dst = to_kvm_sev_info(dst_kvm); @@ -2085,10 +2021,10 @@ int sev_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd) charged = true; } - ret = sev_lock_vcpus_for_migration(kvm, SEV_MIGRATION_SOURCE); + ret = kvm_lock_all_vcpus(kvm); if (ret) goto out_dst_cgroup; - ret = sev_lock_vcpus_for_migration(source_kvm, SEV_MIGRATION_TARGET); + ret = kvm_lock_all_vcpus(source_kvm); if (ret) goto out_dst_vcpu; @@ -2102,9 +2038,9 @@ int sev_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd) ret = 0; out_source_vcpu: - sev_unlock_vcpus_for_migration(source_kvm); + kvm_unlock_all_vcpus(source_kvm); out_dst_vcpu: - sev_unlock_vcpus_for_migration(kvm); + kvm_unlock_all_vcpus(kvm); out_dst_cgroup: /* Operates on the source on success, on the destination on failure. */ if (charged) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index c685fb417e92..3bde4fb5c6aa 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1015,6 +1015,10 @@ static inline struct kvm_vcpu *kvm_get_vcpu_by_id(struct kvm *kvm, int id) void kvm_destroy_vcpus(struct kvm *kvm); +int kvm_trylock_all_vcpus(struct kvm *kvm); +int kvm_lock_all_vcpus(struct kvm *kvm); +void kvm_unlock_all_vcpus(struct kvm *kvm); + void vcpu_load(struct kvm_vcpu *vcpu); void vcpu_put(struct kvm_vcpu *vcpu); diff --git a/include/linux/mutex.h b/include/linux/mutex.h index 2143d05116be..a039fa8c1780 100644 --- a/include/linux/mutex.h +++ b/include/linux/mutex.h @@ -156,16 +156,15 @@ static inline int __devm_mutex_init(struct device *dev, struct mutex *lock) #ifdef CONFIG_DEBUG_LOCK_ALLOC extern void mutex_lock_nested(struct mutex *lock, unsigned int subclass); extern void _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest_lock); - extern int __must_check mutex_lock_interruptible_nested(struct mutex *lock, unsigned int subclass); -extern int __must_check mutex_lock_killable_nested(struct mutex *lock, - unsigned int subclass); +extern int __must_check _mutex_lock_killable(struct mutex *lock, + unsigned int subclass, struct lockdep_map *nest_lock); extern void mutex_lock_io_nested(struct mutex *lock, unsigned int subclass); #define mutex_lock(lock) mutex_lock_nested(lock, 0) #define mutex_lock_interruptible(lock) mutex_lock_interruptible_nested(lock, 0) -#define mutex_lock_killable(lock) mutex_lock_killable_nested(lock, 0) +#define mutex_lock_killable(lock) _mutex_lock_killable(lock, 0, NULL) #define mutex_lock_io(lock) mutex_lock_io_nested(lock, 0) #define mutex_lock_nest_lock(lock, nest_lock) \ @@ -174,6 +173,15 @@ do { \ _mutex_lock_nest_lock(lock, &(nest_lock)->dep_map); \ } while (0) +#define mutex_lock_killable_nest_lock(lock, nest_lock) \ +( \ + typecheck(struct lockdep_map *, &(nest_lock)->dep_map), \ + _mutex_lock_killable(lock, 0, &(nest_lock)->dep_map) \ +) + +#define mutex_lock_killable_nested(lock, subclass) \ + _mutex_lock_killable(lock, subclass, NULL) + #else extern void mutex_lock(struct mutex *lock); extern int __must_check mutex_lock_interruptible(struct mutex *lock); @@ -183,6 +191,7 @@ extern void mutex_lock_io(struct mutex *lock); # define mutex_lock_nested(lock, subclass) mutex_lock(lock) # define mutex_lock_interruptible_nested(lock, subclass) mutex_lock_interruptible(lock) # define mutex_lock_killable_nested(lock, subclass) mutex_lock_killable(lock) +# define mutex_lock_killable_nest_lock(lock, nest_lock) mutex_lock_killable(lock) # define mutex_lock_nest_lock(lock, nest_lock) mutex_lock(lock) # define mutex_lock_io_nested(lock, subclass) mutex_lock_io(lock) #endif @@ -193,7 +202,22 @@ extern void mutex_lock_io(struct mutex *lock); * * Returns 1 if the mutex has been acquired successfully, and 0 on contention. */ + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +extern int _mutex_trylock_nest_lock(struct mutex *lock, struct lockdep_map *nest_lock); + +#define mutex_trylock_nest_lock(lock, nest_lock) \ +( \ + typecheck(struct lockdep_map *, &(nest_lock)->dep_map), \ + _mutex_trylock_nest_lock(lock, &(nest_lock)->dep_map) \ +) + +#define mutex_trylock(lock) _mutex_trylock_nest_lock(lock, NULL) +#else extern int mutex_trylock(struct mutex *lock); +#define mutex_trylock_nest_lock(lock, nest_lock) mutex_trylock(lock) +#endif + extern void mutex_unlock(struct mutex *lock); extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock); diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c index 555e2b3a665a..234923121ff0 100644 --- a/kernel/locking/mutex.c +++ b/kernel/locking/mutex.c @@ -808,11 +808,12 @@ _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest) EXPORT_SYMBOL_GPL(_mutex_lock_nest_lock); int __sched -mutex_lock_killable_nested(struct mutex *lock, unsigned int subclass) +_mutex_lock_killable(struct mutex *lock, unsigned int subclass, + struct lockdep_map *nest) { - return __mutex_lock(lock, TASK_KILLABLE, subclass, NULL, _RET_IP_); + return __mutex_lock(lock, TASK_KILLABLE, subclass, nest, _RET_IP_); } -EXPORT_SYMBOL_GPL(mutex_lock_killable_nested); +EXPORT_SYMBOL_GPL(_mutex_lock_killable); int __sched mutex_lock_interruptible_nested(struct mutex *lock, unsigned int subclass) @@ -1062,6 +1063,7 @@ __ww_mutex_lock_interruptible_slowpath(struct ww_mutex *lock, #endif +#ifndef CONFIG_DEBUG_LOCK_ALLOC /** * mutex_trylock - try to acquire the mutex, without waiting * @lock: the mutex to be acquired @@ -1078,17 +1080,24 @@ __ww_mutex_lock_interruptible_slowpath(struct ww_mutex *lock, */ int __sched mutex_trylock(struct mutex *lock) { + MUTEX_WARN_ON(lock->magic != lock); + return __mutex_trylock(lock); +} +EXPORT_SYMBOL(mutex_trylock); +#else +int __sched _mutex_trylock_nest_lock(struct mutex *lock, struct lockdep_map *nest_lock) +{ bool locked; MUTEX_WARN_ON(lock->magic != lock); - locked = __mutex_trylock(lock); if (locked) - mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_); + mutex_acquire_nest(&lock->dep_map, 0, 1, nest_lock, _RET_IP_); return locked; } -EXPORT_SYMBOL(mutex_trylock); +EXPORT_SYMBOL(_mutex_trylock_nest_lock); +#endif #ifndef CONFIG_DEBUG_LOCK_ALLOC int __sched diff --git a/rust/helpers/mutex.c b/rust/helpers/mutex.c index 06575553eda5..9ab29104bee1 100644 --- a/rust/helpers/mutex.c +++ b/rust/helpers/mutex.c @@ -7,6 +7,11 @@ void rust_helper_mutex_lock(struct mutex *lock) mutex_lock(lock); } +int rust_helper_mutex_trylock(struct mutex *lock) +{ + return mutex_trylock(lock); +} + void rust_helper___mutex_init(struct mutex *mutex, const char *name, struct lock_class_key *key) { diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index b24db92e98f3..eec82775c5bf 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1368,6 +1368,65 @@ static int kvm_vm_release(struct inode *inode, struct file *filp) return 0; } +int kvm_trylock_all_vcpus(struct kvm *kvm) +{ + struct kvm_vcpu *vcpu; + unsigned long i, j; + + lockdep_assert_held(&kvm->lock); + + kvm_for_each_vcpu(i, vcpu, kvm) + if (!mutex_trylock_nest_lock(&vcpu->mutex, &kvm->lock)) + goto out_unlock; + return 0; + +out_unlock: + kvm_for_each_vcpu(j, vcpu, kvm) { + if (i == j) + break; + mutex_unlock(&vcpu->mutex); + } + return -EINTR; +} +EXPORT_SYMBOL_GPL(kvm_trylock_all_vcpus); + +int kvm_lock_all_vcpus(struct kvm *kvm) +{ + struct kvm_vcpu *vcpu; + unsigned long i, j; + int r; + + lockdep_assert_held(&kvm->lock); + + kvm_for_each_vcpu(i, vcpu, kvm) { + r = mutex_lock_killable_nest_lock(&vcpu->mutex, &kvm->lock); + if (r) + goto out_unlock; + } + return 0; + +out_unlock: + kvm_for_each_vcpu(j, vcpu, kvm) { + if (i == j) + break; + mutex_unlock(&vcpu->mutex); + } + return r; +} +EXPORT_SYMBOL_GPL(kvm_lock_all_vcpus); + +void kvm_unlock_all_vcpus(struct kvm *kvm) +{ + struct kvm_vcpu *vcpu; + unsigned long i; + + lockdep_assert_held(&kvm->lock); + + kvm_for_each_vcpu(i, vcpu, kvm) + mutex_unlock(&vcpu->mutex); +} +EXPORT_SYMBOL_GPL(kvm_unlock_all_vcpus); + /* * Allocation size is twice as large as the actual dirty bitmap size. * See kvm_vm_ioctl_get_dirty_log() why this is needed. |