[PATCH 08/10] um: Fix possible race on task->mm

2012-03-24 Thread Anton Vorontsov
Checking for task->mm is dangerous as ->mm might disappear (exit_mm() assigns NULL under task_lock(), so tasklist lock is not enough). We can't use get_task_mm()/mmput() pair as mmput() might sleep, so let's take the task lock while we care about its mm. Note that we should also use find_lock_tas

Re: [PATCH 08/10] um: Fix possible race on task->mm

2012-03-24 Thread Richard Weinberger
Am 24.03.2012 11:30, schrieb Anton Vorontsov: > Checking for task->mm is dangerous as ->mm might disappear (exit_mm() > assigns NULL under task_lock(), so tasklist lock is not enough). > > We can't use get_task_mm()/mmput() pair as mmput() might sleep, > so let's take the task lock while we care a