The patch titled revert "Drop tasklist lock in do_sched_setscheduler" has been removed from the -mm tree. Its filename is for-2618-revert-drop-tasklist-lock-in-do_sched_setscheduler.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ Subject: revert "Drop tasklist lock in do_sched_setscheduler" From: Oleg Nesterov <oleg@xxxxxxxxxx> sched_setscheduler() looks at ->signal->rlim[]. It is unsafe do dereference ->signal unless tasklist_lock or ->siglock is held (or p == current). We pin the task structure, but this can't prevent from release_task()->__exit_signal() which sets ->signal = NULL. Restore tasklist_lock across the setscheduler call. Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> Cc: Greg KH <greg@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxx> --- kernel/sched.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff -puN kernel/sched.c~for-2618-revert-drop-tasklist-lock-in-do_sched_setscheduler kernel/sched.c --- a/kernel/sched.c~for-2618-revert-drop-tasklist-lock-in-do_sched_setscheduler +++ a/kernel/sched.c @@ -4162,10 +4162,8 @@ do_sched_setscheduler(pid_t pid, int pol read_unlock_irq(&tasklist_lock); return -ESRCH; } - get_task_struct(p); - read_unlock_irq(&tasklist_lock); retval = sched_setscheduler(p, policy, &lparam); - put_task_struct(p); + read_unlock_irq(&tasklist_lock); return retval; } _ Patches currently in -mm which might be from oleg@xxxxxxxxxx are pid-implement-transfer_pid-and-use-it-to-simplify-de_thread.patch pid-remove-temporary-debug-code-in-attach_pid.patch rtmutex-clean-up-and-remove-some-extra-spinlocks.patch rtmutex-clean-up-and-remove-some-extra-spinlocks-more.patch elf_core_dump-dont-take-tasklist_lock.patch elf_fdpic_core_dump-dont-take-tasklist_lock.patch has_stopped_jobs-cleanup.patch __dequeue_signal-cleanup.patch do_sched_setscheduler-dont-take-tasklist_lock.patch introduce-is_rt_policy-helper.patch sched_setscheduler-fix-policy-checks.patch reparent_to_init-use-has_rt_policy.patch copy_process-cosmetic-ioprio-tweak.patch futex_find_get_task-dont-take-tasklist_lock.patch sys_get_robust_list-dont-take-tasklist_lock.patch set-exit_dead-state-in-do_exit-not-in-schedule.patch kill-pf_dead-flag.patch introduce-task_dead-state.patch simplify-pid-iterators.patch pidhash-temporary-debug-checks.patch - To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html