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Diffstat (limited to 'kernel/fork.c')
-rw-r--r--kernel/fork.c170
1 files changed, 113 insertions, 57 deletions
diff --git a/kernel/fork.c b/kernel/fork.c
index 7161ebe67cbb..5a90b0f6d668 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -58,6 +58,7 @@
#include <linux/tsacct_kern.h>
#include <linux/cn_proc.h>
#include <linux/freezer.h>
+#include <linux/kaiser.h>
#include <linux/delayacct.h>
#include <linux/taskstats_kern.h>
#include <linux/random.h>
@@ -75,6 +76,8 @@
#include <linux/aio.h>
#include <linux/compiler.h>
#include <linux/sysctl.h>
+#include <linux/kcov.h>
+#include <linux/cpufreq_times.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
@@ -147,18 +150,18 @@ static inline void free_task_struct(struct task_struct *tsk)
}
#endif
-void __weak arch_release_thread_info(struct thread_info *ti)
+void __weak arch_release_thread_stack(unsigned long *stack)
{
}
-#ifndef CONFIG_ARCH_THREAD_INFO_ALLOCATOR
+#ifndef CONFIG_ARCH_THREAD_STACK_ALLOCATOR
/*
* Allocate pages if THREAD_SIZE is >= PAGE_SIZE, otherwise use a
* kmemcache based allocator.
*/
# if THREAD_SIZE >= PAGE_SIZE
-static struct thread_info *alloc_thread_info_node(struct task_struct *tsk,
+static unsigned long *alloc_thread_stack_node(struct task_struct *tsk,
int node)
{
struct page *page = alloc_kmem_pages_node(node, THREADINFO_GFP,
@@ -167,29 +170,32 @@ static struct thread_info *alloc_thread_info_node(struct task_struct *tsk,
return page ? page_address(page) : NULL;
}
-static inline void free_thread_info(struct thread_info *ti)
+static inline void free_thread_stack(unsigned long *stack)
{
- free_kmem_pages((unsigned long)ti, THREAD_SIZE_ORDER);
+ struct page *page = virt_to_page(stack);
+
+ kaiser_unmap_thread_stack(stack);
+ __free_kmem_pages(page, THREAD_SIZE_ORDER);
}
# else
-static struct kmem_cache *thread_info_cache;
+static struct kmem_cache *thread_stack_cache;
-static struct thread_info *alloc_thread_info_node(struct task_struct *tsk,
+static unsigned long *alloc_thread_stack_node(struct task_struct *tsk,
int node)
{
- return kmem_cache_alloc_node(thread_info_cache, THREADINFO_GFP, node);
+ return kmem_cache_alloc_node(thread_stack_cache, THREADINFO_GFP, node);
}
-static void free_thread_info(struct thread_info *ti)
+static void free_thread_stack(unsigned long *stack)
{
- kmem_cache_free(thread_info_cache, ti);
+ kmem_cache_free(thread_stack_cache, stack);
}
-void thread_info_cache_init(void)
+void thread_stack_cache_init(void)
{
- thread_info_cache = kmem_cache_create("thread_info", THREAD_SIZE,
+ thread_stack_cache = kmem_cache_create("thread_stack", THREAD_SIZE,
THREAD_SIZE, 0, NULL);
- BUG_ON(thread_info_cache == NULL);
+ BUG_ON(thread_stack_cache == NULL);
}
# endif
#endif
@@ -212,18 +218,19 @@ struct kmem_cache *vm_area_cachep;
/* SLAB cache for mm_struct structures (tsk->mm) */
static struct kmem_cache *mm_cachep;
-static void account_kernel_stack(struct thread_info *ti, int account)
+static void account_kernel_stack(unsigned long *stack, int account)
{
- struct zone *zone = page_zone(virt_to_page(ti));
+ struct zone *zone = page_zone(virt_to_page(stack));
mod_zone_page_state(zone, NR_KERNEL_STACK, account);
}
void free_task(struct task_struct *tsk)
{
+ cpufreq_task_times_exit(tsk);
account_kernel_stack(tsk->stack, -1);
- arch_release_thread_info(tsk->stack);
- free_thread_info(tsk->stack);
+ arch_release_thread_stack(tsk->stack);
+ free_thread_stack(tsk->stack);
rt_mutex_debug_task_free(tsk);
ftrace_graph_exit_task(tsk);
put_seccomp_filter(tsk);
@@ -331,26 +338,31 @@ void set_task_stack_end_magic(struct task_struct *tsk)
*stackend = STACK_END_MAGIC; /* for overflow detection */
}
-static struct task_struct *dup_task_struct(struct task_struct *orig)
+static struct task_struct *dup_task_struct(struct task_struct *orig, int node)
{
struct task_struct *tsk;
- struct thread_info *ti;
- int node = tsk_fork_get_node(orig);
+ unsigned long *stack;
int err;
+ if (node == NUMA_NO_NODE)
+ node = tsk_fork_get_node(orig);
tsk = alloc_task_struct_node(node);
if (!tsk)
return NULL;
- ti = alloc_thread_info_node(tsk, node);
- if (!ti)
+ stack = alloc_thread_stack_node(tsk, node);
+ if (!stack)
goto free_tsk;
err = arch_dup_task_struct(tsk, orig);
if (err)
- goto free_ti;
+ goto free_stack;
+
+ tsk->stack = stack;
- tsk->stack = ti;
+ err = kaiser_map_thread_stack(tsk->stack);
+ if (err)
+ goto free_stack;
#ifdef CONFIG_SECCOMP
/*
* We must handle setting up seccomp filters once we're under
@@ -367,7 +379,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig)
set_task_stack_end_magic(tsk);
#ifdef CONFIG_CC_STACKPROTECTOR
- tsk->stack_canary = get_random_int();
+ tsk->stack_canary = get_random_long();
#endif
/*
@@ -382,12 +394,14 @@ static struct task_struct *dup_task_struct(struct task_struct *orig)
tsk->task_frag.page = NULL;
tsk->wake_q.next = NULL;
- account_kernel_stack(ti, 1);
+ account_kernel_stack(stack, 1);
+
+ kcov_task_init(tsk);
return tsk;
-free_ti:
- free_thread_info(ti);
+free_stack:
+ free_thread_stack(stack);
free_tsk:
free_task_struct(tsk);
return NULL;
@@ -585,7 +599,8 @@ static void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
#endif
}
-static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p)
+static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p,
+ struct user_namespace *user_ns)
{
mm->mmap = NULL;
mm->mm_rb = RB_ROOT;
@@ -625,6 +640,7 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p)
if (init_new_context(p, mm))
goto fail_nocontext;
+ mm->user_ns = get_user_ns(user_ns);
return mm;
fail_nocontext:
@@ -670,7 +686,7 @@ struct mm_struct *mm_alloc(void)
return NULL;
memset(mm, 0, sizeof(*mm));
- return mm_init(mm, current);
+ return mm_init(mm, current, current_user_ns());
}
/*
@@ -685,10 +701,31 @@ void __mmdrop(struct mm_struct *mm)
destroy_context(mm);
mmu_notifier_mm_destroy(mm);
check_mm(mm);
+ put_user_ns(mm->user_ns);
free_mm(mm);
}
EXPORT_SYMBOL_GPL(__mmdrop);
+static inline void __mmput(struct mm_struct *mm)
+{
+ VM_BUG_ON(atomic_read(&mm->mm_users));
+
+ uprobe_clear_state(mm);
+ exit_aio(mm);
+ ksm_exit(mm);
+ khugepaged_exit(mm); /* must run before exit_mmap */
+ exit_mmap(mm);
+ set_mm_exe_file(mm, NULL);
+ if (!list_empty(&mm->mmlist)) {
+ spin_lock(&mmlist_lock);
+ list_del(&mm->mmlist);
+ spin_unlock(&mmlist_lock);
+ }
+ if (mm->binfmt)
+ module_put(mm->binfmt->module);
+ mmdrop(mm);
+}
+
/*
* Decrement the use count and release all resources for an mm.
*/
@@ -696,24 +733,24 @@ void mmput(struct mm_struct *mm)
{
might_sleep();
+ if (atomic_dec_and_test(&mm->mm_users))
+ __mmput(mm);
+}
+EXPORT_SYMBOL_GPL(mmput);
+
+static void mmput_async_fn(struct work_struct *work)
+{
+ struct mm_struct *mm = container_of(work, struct mm_struct, async_put_work);
+ __mmput(mm);
+}
+
+void mmput_async(struct mm_struct *mm)
+{
if (atomic_dec_and_test(&mm->mm_users)) {
- uprobe_clear_state(mm);
- exit_aio(mm);
- ksm_exit(mm);
- khugepaged_exit(mm); /* must run before exit_mmap */
- exit_mmap(mm);
- set_mm_exe_file(mm, NULL);
- if (!list_empty(&mm->mmlist)) {
- spin_lock(&mmlist_lock);
- list_del(&mm->mmlist);
- spin_unlock(&mmlist_lock);
- }
- if (mm->binfmt)
- module_put(mm->binfmt->module);
- mmdrop(mm);
+ INIT_WORK(&mm->async_put_work, mmput_async_fn);
+ schedule_work(&mm->async_put_work);
}
}
-EXPORT_SYMBOL_GPL(mmput);
/**
* set_mm_exe_file - change a reference to the mm's executable file
@@ -942,7 +979,7 @@ static struct mm_struct *dup_mm(struct task_struct *tsk)
memcpy(mm, oldmm, sizeof(*mm));
- if (!mm_init(mm, tsk))
+ if (!mm_init(mm, tsk, mm->user_ns))
goto fail_nomem;
err = dup_mmap(mm, oldmm);
@@ -1099,7 +1136,9 @@ static int copy_sighand(unsigned long clone_flags, struct task_struct *tsk)
return -ENOMEM;
atomic_set(&sig->count, 1);
+ spin_lock_irq(&current->sighand->siglock);
memcpy(sig->action, current->sighand->action, sizeof(sig->action));
+ spin_unlock_irq(&current->sighand->siglock);
return 0;
}
@@ -1267,7 +1306,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
int __user *child_tidptr,
struct pid *pid,
int trace,
- unsigned long tls)
+ unsigned long tls,
+ int node)
{
int retval;
struct task_struct *p;
@@ -1320,10 +1360,24 @@ static struct task_struct *copy_process(unsigned long clone_flags,
goto fork_out;
retval = -ENOMEM;
- p = dup_task_struct(current);
+ p = dup_task_struct(current, node);
if (!p)
goto fork_out;
+ cpufreq_task_times_init(p);
+
+ /*
+ * This _must_ happen before we call free_task(), i.e. before we jump
+ * to any of the bad_fork_* labels. This is to avoid freeing
+ * p->set_child_tid which is (ab)used as a kthread's data pointer for
+ * kernel threads (PF_KTHREAD).
+ */
+ p->set_child_tid = (clone_flags & CLONE_CHILD_SETTID) ? child_tidptr : NULL;
+ /*
+ * Clear TID on mm_release()?
+ */
+ p->clear_child_tid = (clone_flags & CLONE_CHILD_CLEARTID) ? child_tidptr : NULL;
+
ftrace_graph_init_task(p);
rt_mutex_init_task(p);
@@ -1485,11 +1539,6 @@ static struct task_struct *copy_process(unsigned long clone_flags,
}
}
- p->set_child_tid = (clone_flags & CLONE_CHILD_SETTID) ? child_tidptr : NULL;
- /*
- * Clear TID on mm_release()?
- */
- p->clear_child_tid = (clone_flags & CLONE_CHILD_CLEARTID) ? child_tidptr : NULL;
#ifdef CONFIG_BLOCK
p->plug = NULL;
#endif
@@ -1585,11 +1634,13 @@ static struct task_struct *copy_process(unsigned long clone_flags,
*/
recalc_sigpending();
if (signal_pending(current)) {
- spin_unlock(&current->sighand->siglock);
- write_unlock_irq(&tasklist_lock);
retval = -ERESTARTNOINTR;
goto bad_fork_cancel_cgroup;
}
+ if (unlikely(!(ns_of_pid(pid)->nr_hashed & PIDNS_HASH_ADDING))) {
+ retval = -ENOMEM;
+ goto bad_fork_cancel_cgroup;
+ }
if (likely(p->pid)) {
ptrace_init_task(p, (clone_flags & CLONE_PTRACE) || trace);
@@ -1640,6 +1691,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
return p;
bad_fork_cancel_cgroup:
+ spin_unlock(&current->sighand->siglock);
+ write_unlock_irq(&tasklist_lock);
cgroup_cancel_fork(p, cgrp_ss_priv);
bad_fork_free_pid:
threadgroup_change_end(current);
@@ -1696,7 +1749,8 @@ static inline void init_idle_pids(struct pid_link *links)
struct task_struct *fork_idle(int cpu)
{
struct task_struct *task;
- task = copy_process(CLONE_VM, 0, 0, NULL, &init_struct_pid, 0, 0);
+ task = copy_process(CLONE_VM, 0, 0, NULL, &init_struct_pid, 0, 0,
+ cpu_to_node(cpu));
if (!IS_ERR(task)) {
init_idle_pids(task->pids);
init_idle(task, cpu);
@@ -1741,7 +1795,7 @@ long _do_fork(unsigned long clone_flags,
}
p = copy_process(clone_flags, stack_start, stack_size,
- child_tidptr, NULL, trace, tls);
+ child_tidptr, NULL, trace, tls, NUMA_NO_NODE);
/*
* Do this prior waking up the new thread - the thread pointer
* might get invalid after that point, if the thread exits quickly.
@@ -1750,6 +1804,8 @@ long _do_fork(unsigned long clone_flags,
struct completion vfork;
struct pid *pid;
+ cpufreq_task_times_alloc(p);
+
trace_sched_process_fork(current, p);
pid = get_task_pid(p, PIDTYPE_PID);
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-23 14:54:30 +0000