diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f7dff0457846474c6b1af5822674ffb7a64d2c9b..4a74a7cf0a8bf835800c0cb23d72b17bcb931efa 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 a365ea2383d18c137df14d1fa116fad954d9ca45..e55508b394962d8d77e6fe285cee1a9544214714 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 dcd6e230d16aa7905c1ae075fab469e333f7ef8b..2c9b284036d10217a013e146eba8704123006d65 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 abd24975c9b1d946cec7c85ba7ebe3b820d1c8e4..f8b35df44c60eba57e7b2ec76c068190dd941c79 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 182436b92ba93a95ca6e119108c30d50706b7212..6ec748eccff7e87d7691b92a6d50534d89d4625e 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 70aceefe14d5fa306a3ce78408b9866518030104..e1c7996c018efe688dbe081cc0928f05c5f0bbdd 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 f1a87a690a4cd0555a1bb0ccbd585bb114a498b9..d216e0d2921dafc28b59e9a56dfbd82c660cc0d8 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 63d6246d6dff3caf8b6f7099257f902d50d2de20..6369aeaa70562e92325813857e2ba5c59aadcecb 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 a3454eb56fbf57e3a3868c514cdd72affd578cc4..be28f05bfafa9ee41a53c642f0e384812ea88adf 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 c866a62f766d4ee4bfd5e5bc57e701ef8766159a..57390c7666e5dd8d44bfe9bdf1e503afb13de189 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 7c7362dd2faa9c549500756713ea5512c973cfcf..0205aee44dedd8522be52ffe7d3237dd3819656a 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 392e6af827016cb48d8bfffde0b096463378aaad..133ba78820ee5f2da69b865df43689c0a736ba3e 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 6adac113e96d29b5059ed65ac0522237c9b94388..92f70e4c62529fff53e592f99be9ec12d6372ce2 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 6a17f856f8418b199f78108833d576e18daa142f..381cdf5a9bd1ea5da114e41c068f81c92c879c1e 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 76e7a058b32fc2c4dfb675d262dde082dced208d..0b05545916106cad2f5bd490af19514107a6b9c5 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 8d6449e74431155edcb21308743bd52d449bd8f2..bb2a7e097c7d32d4b86372727005d296335ba72c 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 eff6b88a993f2491b8fb96a2ad553196448966da..82bb1a939c0e496affc2849c1e1af795fe3d5d96 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 412f43453a68ff5260ec46c6211c9249cf9d9cc6..be31a1e0fe78ff23319441d71ad92d3744972f78 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 9263ead9fd32506250d5559feaf008d10a5e5846..0116b449b99346752e542b52dc70ceb5c469e0b7 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,