diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index f7dff0457846..4a74a7cf0a8b 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -7305,8 +7305,9 @@ static void vcpu_load_eoi_exitmap(struct kvm_vcpu *vcpu) kvm_x86_ops->load_eoi_exitmap(vcpu, eoi_exit_bitmap); } -void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm, - unsigned long start, unsigned long end) +int kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm, + unsigned long start, unsigned long end, + bool blockable) { unsigned long apic_address; @@ -7317,6 +7318,8 @@ void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm, apic_address = gfn_to_hva(kvm, APIC_DEFAULT_PHYS_BASE >> PAGE_SHIFT); if (start <= apic_address && apic_address < end) kvm_make_all_cpus_request(kvm, KVM_REQ_APIC_PAGE_RELOAD); + + return 0; } void kvm_vcpu_reload_apic_access_page(struct kvm_vcpu *vcpu) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c index a365ea2383d1..e55508b39496 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c @@ -178,12 +178,18 @@ void amdgpu_mn_unlock(struct amdgpu_mn *mn) * * @amn: our notifier */ -static void amdgpu_mn_read_lock(struct amdgpu_mn *amn) +static int amdgpu_mn_read_lock(struct amdgpu_mn *amn, bool blockable) { - mutex_lock(&amn->read_lock); + if (blockable) + mutex_lock(&amn->read_lock); + else if (!mutex_trylock(&amn->read_lock)) + return -EAGAIN; + if (atomic_inc_return(&amn->recursion) == 1) down_read_non_owner(&amn->lock); mutex_unlock(&amn->read_lock); + + return 0; } /** @@ -239,10 +245,11 @@ static void amdgpu_mn_invalidate_node(struct amdgpu_mn_node *node, * Block for operations on BOs to finish and mark pages as accessed and * potentially dirty. */ -static void amdgpu_mn_invalidate_range_start_gfx(struct mmu_notifier *mn, +static int amdgpu_mn_invalidate_range_start_gfx(struct mmu_notifier *mn, struct mm_struct *mm, unsigned long start, - unsigned long end) + unsigned long end, + bool blockable) { struct amdgpu_mn *amn = container_of(mn, struct amdgpu_mn, mn); struct interval_tree_node *it; @@ -250,17 +257,28 @@ static void amdgpu_mn_invalidate_range_start_gfx(struct mmu_notifier *mn, /* notification is exclusive, but interval is inclusive */ end -= 1; - amdgpu_mn_read_lock(amn); + /* TODO we should be able to split locking for interval tree and + * amdgpu_mn_invalidate_node + */ + if (amdgpu_mn_read_lock(amn, blockable)) + return -EAGAIN; it = interval_tree_iter_first(&amn->objects, start, end); while (it) { struct amdgpu_mn_node *node; + if (!blockable) { + amdgpu_mn_read_unlock(amn); + return -EAGAIN; + } + node = container_of(it, struct amdgpu_mn_node, it); it = interval_tree_iter_next(it, start, end); amdgpu_mn_invalidate_node(node, start, end); } + + return 0; } /** @@ -275,10 +293,11 @@ static void amdgpu_mn_invalidate_range_start_gfx(struct mmu_notifier *mn, * necessitates evicting all user-mode queues of the process. The BOs * are restorted in amdgpu_mn_invalidate_range_end_hsa. */ -static void amdgpu_mn_invalidate_range_start_hsa(struct mmu_notifier *mn, +static int amdgpu_mn_invalidate_range_start_hsa(struct mmu_notifier *mn, struct mm_struct *mm, unsigned long start, - unsigned long end) + unsigned long end, + bool blockable) { struct amdgpu_mn *amn = container_of(mn, struct amdgpu_mn, mn); struct interval_tree_node *it; @@ -286,13 +305,19 @@ static void amdgpu_mn_invalidate_range_start_hsa(struct mmu_notifier *mn, /* notification is exclusive, but interval is inclusive */ end -= 1; - amdgpu_mn_read_lock(amn); + if (amdgpu_mn_read_lock(amn, blockable)) + return -EAGAIN; it = interval_tree_iter_first(&amn->objects, start, end); while (it) { struct amdgpu_mn_node *node; struct amdgpu_bo *bo; + if (!blockable) { + amdgpu_mn_read_unlock(amn); + return -EAGAIN; + } + node = container_of(it, struct amdgpu_mn_node, it); it = interval_tree_iter_next(it, start, end); @@ -304,6 +329,8 @@ static void amdgpu_mn_invalidate_range_start_hsa(struct mmu_notifier *mn, amdgpu_amdkfd_evict_userptr(mem, mm); } } + + return 0; } /** diff --git a/drivers/gpu/drm/i915/i915_gem_userptr.c b/drivers/gpu/drm/i915/i915_gem_userptr.c index dcd6e230d16a..2c9b284036d1 100644 --- a/drivers/gpu/drm/i915/i915_gem_userptr.c +++ b/drivers/gpu/drm/i915/i915_gem_userptr.c @@ -112,10 +112,11 @@ static void del_object(struct i915_mmu_object *mo) mo->attached = false; } -static void i915_gem_userptr_mn_invalidate_range_start(struct mmu_notifier *_mn, +static int i915_gem_userptr_mn_invalidate_range_start(struct mmu_notifier *_mn, struct mm_struct *mm, unsigned long start, - unsigned long end) + unsigned long end, + bool blockable) { struct i915_mmu_notifier *mn = container_of(_mn, struct i915_mmu_notifier, mn); @@ -124,7 +125,7 @@ static void i915_gem_userptr_mn_invalidate_range_start(struct mmu_notifier *_mn, LIST_HEAD(cancelled); if (RB_EMPTY_ROOT(&mn->objects.rb_root)) - return; + return 0; /* interval ranges are inclusive, but invalidate range is exclusive */ end--; @@ -132,6 +133,10 @@ static void i915_gem_userptr_mn_invalidate_range_start(struct mmu_notifier *_mn, spin_lock(&mn->lock); it = interval_tree_iter_first(&mn->objects, start, end); while (it) { + if (!blockable) { + spin_unlock(&mn->lock); + return -EAGAIN; + } /* The mmu_object is released late when destroying the * GEM object so it is entirely possible to gain a * reference on an object in the process of being freed @@ -154,6 +159,8 @@ static void i915_gem_userptr_mn_invalidate_range_start(struct mmu_notifier *_mn, if (!list_empty(&cancelled)) flush_workqueue(mn->wq); + + return 0; } static const struct mmu_notifier_ops i915_gem_userptr_notifier = { diff --git a/drivers/gpu/drm/radeon/radeon_mn.c b/drivers/gpu/drm/radeon/radeon_mn.c index abd24975c9b1..f8b35df44c60 100644 --- a/drivers/gpu/drm/radeon/radeon_mn.c +++ b/drivers/gpu/drm/radeon/radeon_mn.c @@ -118,19 +118,27 @@ static void radeon_mn_release(struct mmu_notifier *mn, * We block for all BOs between start and end to be idle and * unmap them by move them into system domain again. */ -static void radeon_mn_invalidate_range_start(struct mmu_notifier *mn, +static int radeon_mn_invalidate_range_start(struct mmu_notifier *mn, struct mm_struct *mm, unsigned long start, - unsigned long end) + unsigned long end, + bool blockable) { struct radeon_mn *rmn = container_of(mn, struct radeon_mn, mn); struct ttm_operation_ctx ctx = { false, false }; struct interval_tree_node *it; + int ret = 0; /* notification is exclusive, but interval is inclusive */ end -= 1; - mutex_lock(&rmn->lock); + /* TODO we should be able to split locking for interval tree and + * the tear down. + */ + if (blockable) + mutex_lock(&rmn->lock); + else if (!mutex_trylock(&rmn->lock)) + return -EAGAIN; it = interval_tree_iter_first(&rmn->objects, start, end); while (it) { @@ -138,6 +146,11 @@ static void radeon_mn_invalidate_range_start(struct mmu_notifier *mn, struct radeon_bo *bo; long r; + if (!blockable) { + ret = -EAGAIN; + goto out_unlock; + } + node = container_of(it, struct radeon_mn_node, it); it = interval_tree_iter_next(it, start, end); @@ -166,7 +179,10 @@ static void radeon_mn_invalidate_range_start(struct mmu_notifier *mn, } } +out_unlock: mutex_unlock(&rmn->lock); + + return ret; } static const struct mmu_notifier_ops radeon_mn_ops = { diff --git a/drivers/infiniband/core/umem_odp.c b/drivers/infiniband/core/umem_odp.c index 182436b92ba9..6ec748eccff7 100644 --- a/drivers/infiniband/core/umem_odp.c +++ b/drivers/infiniband/core/umem_odp.c @@ -186,6 +186,7 @@ static void ib_umem_notifier_release(struct mmu_notifier *mn, rbt_ib_umem_for_each_in_range(&context->umem_tree, 0, ULLONG_MAX, ib_umem_notifier_release_trampoline, + true, NULL); up_read(&context->umem_rwsem); } @@ -207,22 +208,31 @@ static int invalidate_range_start_trampoline(struct ib_umem *item, u64 start, return 0; } -static void ib_umem_notifier_invalidate_range_start(struct mmu_notifier *mn, +static int ib_umem_notifier_invalidate_range_start(struct mmu_notifier *mn, struct mm_struct *mm, unsigned long start, - unsigned long end) + unsigned long end, + bool blockable) { struct ib_ucontext *context = container_of(mn, struct ib_ucontext, mn); + int ret; if (!context->invalidate_range) - return; + return 0; + + if (blockable) + down_read(&context->umem_rwsem); + else if (!down_read_trylock(&context->umem_rwsem)) + return -EAGAIN; ib_ucontext_notifier_start_account(context); - down_read(&context->umem_rwsem); - rbt_ib_umem_for_each_in_range(&context->umem_tree, start, + ret = rbt_ib_umem_for_each_in_range(&context->umem_tree, start, end, - invalidate_range_start_trampoline, NULL); + invalidate_range_start_trampoline, + blockable, NULL); up_read(&context->umem_rwsem); + + return ret; } static int invalidate_range_end_trampoline(struct ib_umem *item, u64 start, @@ -242,10 +252,15 @@ static void ib_umem_notifier_invalidate_range_end(struct mmu_notifier *mn, if (!context->invalidate_range) return; + /* + * TODO: we currently bail out if there is any sleepable work to be done + * in ib_umem_notifier_invalidate_range_start so we shouldn't really block + * here. But this is ugly and fragile. + */ down_read(&context->umem_rwsem); rbt_ib_umem_for_each_in_range(&context->umem_tree, start, end, - invalidate_range_end_trampoline, NULL); + invalidate_range_end_trampoline, true, NULL); up_read(&context->umem_rwsem); ib_ucontext_notifier_end_account(context); } @@ -798,6 +813,7 @@ EXPORT_SYMBOL(ib_umem_odp_unmap_dma_pages); int rbt_ib_umem_for_each_in_range(struct rb_root_cached *root, u64 start, u64 last, umem_call_back cb, + bool blockable, void *cookie) { int ret_val = 0; @@ -809,6 +825,9 @@ int rbt_ib_umem_for_each_in_range(struct rb_root_cached *root, for (node = rbt_ib_umem_iter_first(root, start, last - 1); node; node = next) { + /* TODO move the blockable decision up to the callback */ + if (!blockable) + return -EAGAIN; next = rbt_ib_umem_iter_next(node, start, last - 1); umem = container_of(node, struct ib_umem_odp, interval_tree); ret_val = cb(umem->umem, start, last, cookie) || ret_val; diff --git a/drivers/infiniband/hw/hfi1/mmu_rb.c b/drivers/infiniband/hw/hfi1/mmu_rb.c index 70aceefe14d5..e1c7996c018e 100644 --- a/drivers/infiniband/hw/hfi1/mmu_rb.c +++ b/drivers/infiniband/hw/hfi1/mmu_rb.c @@ -67,9 +67,9 @@ struct mmu_rb_handler { static unsigned long mmu_node_start(struct mmu_rb_node *); static unsigned long mmu_node_last(struct mmu_rb_node *); -static void mmu_notifier_range_start(struct mmu_notifier *, +static int mmu_notifier_range_start(struct mmu_notifier *, struct mm_struct *, - unsigned long, unsigned long); + unsigned long, unsigned long, bool); static struct mmu_rb_node *__mmu_rb_search(struct mmu_rb_handler *, unsigned long, unsigned long); static void do_remove(struct mmu_rb_handler *handler, @@ -284,10 +284,11 @@ void hfi1_mmu_rb_remove(struct mmu_rb_handler *handler, handler->ops->remove(handler->ops_arg, node); } -static void mmu_notifier_range_start(struct mmu_notifier *mn, +static int mmu_notifier_range_start(struct mmu_notifier *mn, struct mm_struct *mm, unsigned long start, - unsigned long end) + unsigned long end, + bool blockable) { struct mmu_rb_handler *handler = container_of(mn, struct mmu_rb_handler, mn); @@ -313,6 +314,8 @@ static void mmu_notifier_range_start(struct mmu_notifier *mn, if (added) queue_work(handler->wq, &handler->del_work); + + return 0; } /* diff --git a/drivers/infiniband/hw/mlx5/odp.c b/drivers/infiniband/hw/mlx5/odp.c index f1a87a690a4c..d216e0d2921d 100644 --- a/drivers/infiniband/hw/mlx5/odp.c +++ b/drivers/infiniband/hw/mlx5/odp.c @@ -488,7 +488,7 @@ void mlx5_ib_free_implicit_mr(struct mlx5_ib_mr *imr) down_read(&ctx->umem_rwsem); rbt_ib_umem_for_each_in_range(&ctx->umem_tree, 0, ULLONG_MAX, - mr_leaf_free, imr); + mr_leaf_free, true, imr); up_read(&ctx->umem_rwsem); wait_event(imr->q_leaf_free, !atomic_read(&imr->num_leaf_free)); diff --git a/drivers/misc/mic/scif/scif_dma.c b/drivers/misc/mic/scif/scif_dma.c index 63d6246d6dff..6369aeaa7056 100644 --- a/drivers/misc/mic/scif/scif_dma.c +++ b/drivers/misc/mic/scif/scif_dma.c @@ -200,15 +200,18 @@ static void scif_mmu_notifier_release(struct mmu_notifier *mn, schedule_work(&scif_info.misc_work); } -static void scif_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, +static int scif_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, struct mm_struct *mm, unsigned long start, - unsigned long end) + unsigned long end, + bool blockable) { struct scif_mmu_notif *mmn; mmn = container_of(mn, struct scif_mmu_notif, ep_mmu_notifier); scif_rma_destroy_tcw(mmn, start, end - start); + + return 0; } static void scif_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn, diff --git a/drivers/misc/sgi-gru/grutlbpurge.c b/drivers/misc/sgi-gru/grutlbpurge.c index a3454eb56fbf..be28f05bfafa 100644 --- a/drivers/misc/sgi-gru/grutlbpurge.c +++ b/drivers/misc/sgi-gru/grutlbpurge.c @@ -219,9 +219,10 @@ void gru_flush_all_tlb(struct gru_state *gru) /* * MMUOPS notifier callout functions */ -static void gru_invalidate_range_start(struct mmu_notifier *mn, +static int gru_invalidate_range_start(struct mmu_notifier *mn, struct mm_struct *mm, - unsigned long start, unsigned long end) + unsigned long start, unsigned long end, + bool blockable) { struct gru_mm_struct *gms = container_of(mn, struct gru_mm_struct, ms_notifier); @@ -231,6 +232,8 @@ static void gru_invalidate_range_start(struct mmu_notifier *mn, gru_dbg(grudev, "gms %p, start 0x%lx, end 0x%lx, act %d\n", gms, start, end, atomic_read(&gms->ms_range_active)); gru_flush_tlb_range(gms, start, end - start); + + return 0; } static void gru_invalidate_range_end(struct mmu_notifier *mn, diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c index c866a62f766d..57390c7666e5 100644 --- a/drivers/xen/gntdev.c +++ b/drivers/xen/gntdev.c @@ -479,18 +479,25 @@ static const struct vm_operations_struct gntdev_vmops = { /* ------------------------------------------------------------------ */ +static bool in_range(struct gntdev_grant_map *map, + unsigned long start, unsigned long end) +{ + if (!map->vma) + return false; + if (map->vma->vm_start >= end) + return false; + if (map->vma->vm_end <= start) + return false; + + return true; +} + static void unmap_if_in_range(struct gntdev_grant_map *map, unsigned long start, unsigned long end) { unsigned long mstart, mend; int err; - if (!map->vma) - return; - if (map->vma->vm_start >= end) - return; - if (map->vma->vm_end <= start) - return; mstart = max(start, map->vma->vm_start); mend = min(end, map->vma->vm_end); pr_debug("map %d+%d (%lx %lx), range %lx %lx, mrange %lx %lx\n", @@ -503,21 +510,40 @@ static void unmap_if_in_range(struct gntdev_grant_map *map, WARN_ON(err); } -static void mn_invl_range_start(struct mmu_notifier *mn, +static int mn_invl_range_start(struct mmu_notifier *mn, struct mm_struct *mm, - unsigned long start, unsigned long end) + unsigned long start, unsigned long end, + bool blockable) { struct gntdev_priv *priv = container_of(mn, struct gntdev_priv, mn); struct gntdev_grant_map *map; + int ret = 0; + + /* TODO do we really need a mutex here? */ + if (blockable) + mutex_lock(&priv->lock); + else if (!mutex_trylock(&priv->lock)) + return -EAGAIN; - mutex_lock(&priv->lock); list_for_each_entry(map, &priv->maps, next) { + if (in_range(map, start, end)) { + ret = -EAGAIN; + goto out_unlock; + } unmap_if_in_range(map, start, end); } list_for_each_entry(map, &priv->freeable_maps, next) { + if (in_range(map, start, end)) { + ret = -EAGAIN; + goto out_unlock; + } unmap_if_in_range(map, start, end); } + +out_unlock: mutex_unlock(&priv->lock); + + return ret; } static void mn_release(struct mmu_notifier *mn, diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 7c7362dd2faa..0205aee44ded 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1289,8 +1289,8 @@ static inline long kvm_arch_vcpu_async_ioctl(struct file *filp, } #endif /* CONFIG_HAVE_KVM_VCPU_ASYNC_IOCTL */ -void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm, - unsigned long start, unsigned long end); +int kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm, + unsigned long start, unsigned long end, bool blockable); #ifdef CONFIG_HAVE_KVM_VCPU_RUN_PID_CHANGE int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu); diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h index 392e6af82701..133ba78820ee 100644 --- a/include/linux/mmu_notifier.h +++ b/include/linux/mmu_notifier.h @@ -151,13 +151,15 @@ struct mmu_notifier_ops { * address space but may still be referenced by sptes until * the last refcount is dropped. * - * If both of these callbacks cannot block, and invalidate_range - * cannot block, mmu_notifier_ops.flags should have - * MMU_INVALIDATE_DOES_NOT_BLOCK set. + * If blockable argument is set to false then the callback cannot + * sleep and has to return with -EAGAIN. 0 should be returned + * otherwise. + * */ - void (*invalidate_range_start)(struct mmu_notifier *mn, + int (*invalidate_range_start)(struct mmu_notifier *mn, struct mm_struct *mm, - unsigned long start, unsigned long end); + unsigned long start, unsigned long end, + bool blockable); void (*invalidate_range_end)(struct mmu_notifier *mn, struct mm_struct *mm, unsigned long start, unsigned long end); @@ -229,8 +231,9 @@ extern int __mmu_notifier_test_young(struct mm_struct *mm, unsigned long address); extern void __mmu_notifier_change_pte(struct mm_struct *mm, unsigned long address, pte_t pte); -extern void __mmu_notifier_invalidate_range_start(struct mm_struct *mm, - unsigned long start, unsigned long end); +extern int __mmu_notifier_invalidate_range_start(struct mm_struct *mm, + unsigned long start, unsigned long end, + bool blockable); extern void __mmu_notifier_invalidate_range_end(struct mm_struct *mm, unsigned long start, unsigned long end, bool only_end); @@ -281,7 +284,15 @@ static inline void mmu_notifier_invalidate_range_start(struct mm_struct *mm, unsigned long start, unsigned long end) { if (mm_has_notifiers(mm)) - __mmu_notifier_invalidate_range_start(mm, start, end); + __mmu_notifier_invalidate_range_start(mm, start, end, true); +} + +static inline int mmu_notifier_invalidate_range_start_nonblock(struct mm_struct *mm, + unsigned long start, unsigned long end) +{ + if (mm_has_notifiers(mm)) + return __mmu_notifier_invalidate_range_start(mm, start, end, false); + return 0; } static inline void mmu_notifier_invalidate_range_end(struct mm_struct *mm, @@ -461,6 +472,12 @@ static inline void mmu_notifier_invalidate_range_start(struct mm_struct *mm, { } +static inline int mmu_notifier_invalidate_range_start_nonblock(struct mm_struct *mm, + unsigned long start, unsigned long end) +{ + return 0; +} + static inline void mmu_notifier_invalidate_range_end(struct mm_struct *mm, unsigned long start, unsigned long end) { diff --git a/include/linux/oom.h b/include/linux/oom.h index 6adac113e96d..92f70e4c6252 100644 --- a/include/linux/oom.h +++ b/include/linux/oom.h @@ -95,7 +95,7 @@ static inline int check_stable_address_space(struct mm_struct *mm) return 0; } -void __oom_reap_task_mm(struct mm_struct *mm); +bool __oom_reap_task_mm(struct mm_struct *mm); extern unsigned long oom_badness(struct task_struct *p, struct mem_cgroup *memcg, const nodemask_t *nodemask, diff --git a/include/rdma/ib_umem_odp.h b/include/rdma/ib_umem_odp.h index 6a17f856f841..381cdf5a9bd1 100644 --- a/include/rdma/ib_umem_odp.h +++ b/include/rdma/ib_umem_odp.h @@ -119,7 +119,8 @@ typedef int (*umem_call_back)(struct ib_umem *item, u64 start, u64 end, */ int rbt_ib_umem_for_each_in_range(struct rb_root_cached *root, u64 start, u64 end, - umem_call_back cb, void *cookie); + umem_call_back cb, + bool blockable, void *cookie); /* * Find first region intersecting with address range. diff --git a/mm/hmm.c b/mm/hmm.c index 76e7a058b32f..0b0554591610 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -177,16 +177,19 @@ static void hmm_release(struct mmu_notifier *mn, struct mm_struct *mm) up_write(&hmm->mirrors_sem); } -static void hmm_invalidate_range_start(struct mmu_notifier *mn, +static int hmm_invalidate_range_start(struct mmu_notifier *mn, struct mm_struct *mm, unsigned long start, - unsigned long end) + unsigned long end, + bool blockable) { struct hmm *hmm = mm->hmm; VM_BUG_ON(!hmm); atomic_inc(&hmm->sequence); + + return 0; } static void hmm_invalidate_range_end(struct mmu_notifier *mn, diff --git a/mm/mmap.c b/mm/mmap.c index 8d6449e74431..bb2a7e097c7d 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -3064,7 +3064,7 @@ void exit_mmap(struct mm_struct *mm) * reliably test it. */ mutex_lock(&oom_lock); - __oom_reap_task_mm(mm); + (void)__oom_reap_task_mm(mm); mutex_unlock(&oom_lock); set_bit(MMF_OOM_SKIP, &mm->flags); diff --git a/mm/mmu_notifier.c b/mm/mmu_notifier.c index eff6b88a993f..82bb1a939c0e 100644 --- a/mm/mmu_notifier.c +++ b/mm/mmu_notifier.c @@ -174,18 +174,29 @@ void __mmu_notifier_change_pte(struct mm_struct *mm, unsigned long address, srcu_read_unlock(&srcu, id); } -void __mmu_notifier_invalidate_range_start(struct mm_struct *mm, - unsigned long start, unsigned long end) +int __mmu_notifier_invalidate_range_start(struct mm_struct *mm, + unsigned long start, unsigned long end, + bool blockable) { struct mmu_notifier *mn; + int ret = 0; int id; id = srcu_read_lock(&srcu); hlist_for_each_entry_rcu(mn, &mm->mmu_notifier_mm->list, hlist) { - if (mn->ops->invalidate_range_start) - mn->ops->invalidate_range_start(mn, mm, start, end); + if (mn->ops->invalidate_range_start) { + int _ret = mn->ops->invalidate_range_start(mn, mm, start, end, blockable); + if (_ret) { + pr_info("%pS callback failed with %d in %sblockable context.\n", + mn->ops->invalidate_range_start, _ret, + !blockable ? "non-" : ""); + ret = _ret; + } + } } srcu_read_unlock(&srcu, id); + + return ret; } EXPORT_SYMBOL_GPL(__mmu_notifier_invalidate_range_start); diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 412f43453a68..be31a1e0fe78 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -487,9 +487,10 @@ static DECLARE_WAIT_QUEUE_HEAD(oom_reaper_wait); static struct task_struct *oom_reaper_list; static DEFINE_SPINLOCK(oom_reaper_lock); -void __oom_reap_task_mm(struct mm_struct *mm) +bool __oom_reap_task_mm(struct mm_struct *mm) { struct vm_area_struct *vma; + bool ret = true; /* * Tell all users of get_user/copy_from_user etc... that the content @@ -519,12 +520,17 @@ void __oom_reap_task_mm(struct mm_struct *mm) struct mmu_gather tlb; tlb_gather_mmu(&tlb, mm, start, end); - mmu_notifier_invalidate_range_start(mm, start, end); + if (mmu_notifier_invalidate_range_start_nonblock(mm, start, end)) { + ret = false; + continue; + } unmap_page_range(&tlb, vma, start, end, NULL); mmu_notifier_invalidate_range_end(mm, start, end); tlb_finish_mmu(&tlb, start, end); } } + + return ret; } static bool oom_reap_task_mm(struct task_struct *tsk, struct mm_struct *mm) @@ -553,18 +559,6 @@ static bool oom_reap_task_mm(struct task_struct *tsk, struct mm_struct *mm) goto unlock_oom; } - /* - * If the mm has invalidate_{start,end}() notifiers that could block, - * sleep to give the oom victim some more time. - * TODO: we really want to get rid of this ugly hack and make sure that - * notifiers cannot block for unbounded amount of time - */ - if (mm_has_blockable_invalidate_notifiers(mm)) { - up_read(&mm->mmap_sem); - schedule_timeout_idle(HZ); - goto unlock_oom; - } - /* * MMF_OOM_SKIP is set by exit_mmap when the OOM reaper can't * work on the mm anymore. The check for MMF_OOM_SKIP must run @@ -579,7 +573,12 @@ static bool oom_reap_task_mm(struct task_struct *tsk, struct mm_struct *mm) trace_start_task_reaping(tsk->pid); - __oom_reap_task_mm(mm); + /* failed to reap part of the address space. Try again later */ + if (!__oom_reap_task_mm(mm)) { + up_read(&mm->mmap_sem); + ret = false; + goto unlock_oom; + } pr_info("oom_reaper: reaped process %d (%s), now anon-rss:%lukB, file-rss:%lukB, shmem-rss:%lukB\n", task_pid_nr(tsk), tsk->comm, diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 9263ead9fd32..0116b449b993 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -140,9 +140,10 @@ static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm); static unsigned long long kvm_createvm_count; static unsigned long long kvm_active_vms; -__weak void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm, - unsigned long start, unsigned long end) +__weak int kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm, + unsigned long start, unsigned long end, bool blockable) { + return 0; } bool kvm_is_reserved_pfn(kvm_pfn_t pfn) @@ -360,13 +361,15 @@ static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn, srcu_read_unlock(&kvm->srcu, idx); } -static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, +static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, struct mm_struct *mm, unsigned long start, - unsigned long end) + unsigned long end, + bool blockable) { struct kvm *kvm = mmu_notifier_to_kvm(mn); int need_tlb_flush = 0, idx; + int ret; idx = srcu_read_lock(&kvm->srcu); spin_lock(&kvm->mmu_lock); @@ -384,9 +387,11 @@ static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, spin_unlock(&kvm->mmu_lock); - kvm_arch_mmu_notifier_invalidate_range(kvm, start, end); + ret = kvm_arch_mmu_notifier_invalidate_range(kvm, start, end, blockable); srcu_read_unlock(&kvm->srcu, idx); + + return ret; } static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,