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charset="UTF-8" X-Stat-Signature: okbqfh56bcdy9fjx1p31fb99g5bd388j X-Rspam-User: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 80733C0009 X-HE-Tag: 1790617313-929089 X-HE-Meta: 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 FhAPcMU9 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Pasha Tatashin In preparation for the partially populated stacks, separate out the __vmalloc_node and vfree calls from the vmap based stack allocations. Signed-off-by: Pasha Tatashin [Fix a bug in original patch: free_vmap_stack(vm_area->addr)] Signed-off-by: Linus Walleij [Add missing free_vmap_stack conversion, fix typos, rebase] Signed-off-by: David Stevens [Resolved conflict in alloc_thread_stack_node(), update commit msg] Signed-off-by: Mostafa Saleh --- kernel/fork.c | 35 +++++++++++++++++++++++------------ 1 file changed, 23 insertions(+), 12 deletions(-) diff --git a/kernel/fork.c b/kernel/fork.c index 473878d7f62f..3f1c46d8f7ec 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -272,6 +272,21 @@ static bool try_release_thread_stack_to_cache(struct vm_struct *vm_area) return false; } +static inline struct vm_struct *alloc_vmap_stack(int node) +{ + void *stack; + + stack = __vmalloc_node(THREAD_SIZE, THREAD_ALIGN, GFP_VMAP_STACK, + node, __builtin_return_address(0)); + + return stack ? find_vm_area(stack) : NULL; +} + +static inline void free_vmap_stack(struct vm_struct *vm_area) +{ + vfree(vm_area->addr); +} + static void thread_stack_free_rcu(struct rcu_head *rh) { struct vm_stack *vm_stack = container_of(rh, struct vm_stack, rcu); @@ -280,7 +295,7 @@ static void thread_stack_free_rcu(struct rcu_head *rh) if (try_release_thread_stack_to_cache(vm_stack->stack_vm_area)) return; - vfree(vm_area->addr); + free_vmap_stack(vm_area); } static void thread_stack_delayed_free(struct task_struct *tsk) @@ -307,7 +322,7 @@ static int free_vm_stack_cache(unsigned int cpu) if (!vm_area) continue; - vfree(vm_area->addr); + free_vmap_stack(vm_area); cached_vm_stack_areas[i] = NULL; } @@ -336,14 +351,14 @@ static int memcg_charge_kernel_stack(struct vm_struct *vm_area) static int alloc_thread_stack_node(struct task_struct *tsk, int node) { struct vm_struct *vm_area; - void *stack; vm_area = alloc_thread_stack_node_from_cache(tsk, node); if (vm_area) { unsigned long offset = 0; + void *stack; if (memcg_charge_kernel_stack(vm_area)) { - vfree(vm_area->addr); + free_vmap_stack(vm_area); return -ENOMEM; } @@ -364,15 +379,12 @@ static int alloc_thread_stack_node(struct task_struct *tsk, int node) return 0; } - stack = __vmalloc_node(THREAD_SIZE, THREAD_ALIGN, - GFP_VMAP_STACK, - node, __builtin_return_address(0)); - if (!stack) + vm_area = alloc_vmap_stack(node); + if (!vm_area) return -ENOMEM; - vm_area = find_vm_area(stack); if (memcg_charge_kernel_stack(vm_area)) { - vfree(stack); + free_vmap_stack(vm_area); return -ENOMEM; } /* @@ -381,8 +393,7 @@ static int alloc_thread_stack_node(struct task_struct *tsk, int node) * so cache the vm_struct. */ tsk->stack_vm_area = vm_area; - stack = kasan_reset_tag(stack); - tsk->stack = stack; + tsk->stack = kasan_reset_tag(vm_area->addr); return 0; } -- 2.56.0.rc1.315.gc6ed9934b7-goog