diff options
Diffstat (limited to 'kernel/fork.c')
-rw-r--r-- | kernel/fork.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index 9a05bd93f8e7..997ac1d584f7 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -315,6 +315,9 @@ static void account_kernel_stack(struct task_struct *tsk, int account) static void release_task_stack(struct task_struct *tsk) { + if (WARN_ON(tsk->state != TASK_DEAD)) + return; /* Better to leak the stack than to free prematurely */ + account_kernel_stack(tsk, -1); arch_release_thread_stack(tsk->stack); free_thread_stack(tsk); @@ -359,6 +362,12 @@ static inline void free_signal_struct(struct signal_struct *sig) { taskstats_tgid_free(sig); sched_autogroup_exit(sig); + /* + * __mmdrop is not safe to call from softirq context on x86 due to + * pgd_dtor so postpone it to the async context + */ + if (sig->oom_mm) + mmdrop_async(sig->oom_mm); kmem_cache_free(signal_cachep, sig); } @@ -541,7 +550,8 @@ free_tsk: } #ifdef CONFIG_MMU -static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) +static __latent_entropy int dup_mmap(struct mm_struct *mm, + struct mm_struct *oldmm) { struct vm_area_struct *mpnt, *tmp, *prev, **pprev; struct rb_node **rb_link, *rb_parent; @@ -848,6 +858,7 @@ static inline void __mmput(struct mm_struct *mm) ksm_exit(mm); khugepaged_exit(mm); /* must run before exit_mmap */ exit_mmap(mm); + mm_put_huge_zero_page(mm); set_mm_exe_file(mm, NULL); if (!list_empty(&mm->mmlist)) { spin_lock(&mmlist_lock); @@ -856,6 +867,7 @@ static inline void __mmput(struct mm_struct *mm) } if (mm->binfmt) module_put(mm->binfmt->module); + set_bit(MMF_OOM_SKIP, &mm->flags); mmdrop(mm); } @@ -1433,7 +1445,8 @@ init_task_pid(struct task_struct *task, enum pid_type type, struct pid *pid) * parts of the process environment (as per the clone * flags). The actual kick-off is left to the caller. */ -static struct task_struct *copy_process(unsigned long clone_flags, +static __latent_entropy struct task_struct *copy_process( + unsigned long clone_flags, unsigned long stack_start, unsigned long stack_size, int __user *child_tidptr, @@ -1852,6 +1865,7 @@ bad_fork_cleanup_count: atomic_dec(&p->cred->user->processes); exit_creds(p); bad_fork_free: + p->state = TASK_DEAD; put_task_stack(p); free_task(p); fork_out: @@ -1918,6 +1932,7 @@ long _do_fork(unsigned long clone_flags, p = copy_process(clone_flags, stack_start, stack_size, child_tidptr, NULL, trace, tls, NUMA_NO_NODE); + add_latent_entropy(); /* * Do this prior waking up the new thread - the thread pointer * might get invalid after that point, if the thread exits quickly. |