On Thu, Nov 08, 2007 at 03:48:05PM -0800, [EMAIL PROTECTED] wrote: > With CONFIG_FAIR_CGROUP_SCHED=y, following commands on 2.6.24-rc1 crash > the system.
Thanks for reporting the problem. It was caused because of the fact that current task isn't kept in its runqueue in case of sched_fair class tasks. With the patch below, I could run ns_exec w/o any crash. Can you pls verify it works for you as well? Ingo, Once Suka verifies that the patch fixes his crash, I would request you to include the same in your tree and route it to Linus. -- current task is not present in its runqueue in case of sched_fair class tasks. Take care of this fact in rt_mutex_setprio(), sched_setscheduler() and sched_move_task() routines. Signed-off-by : Srivatsa Vaddagiri <[EMAIL PROTECTED]> --- kernel/sched.c | 45 +++++++++++++++++++++++++-------------------- 1 files changed, 25 insertions(+), 20 deletions(-) Index: current/kernel/sched.c =================================================================== --- current.orig/kernel/sched.c +++ current/kernel/sched.c @@ -3986,11 +3986,13 @@ void rt_mutex_setprio(struct task_struct oldprio = p->prio; on_rq = p->se.on_rq; running = task_running(rq, p); - if (on_rq) { + if (on_rq) dequeue_task(rq, p, 0); - if (running) - p->sched_class->put_prev_task(rq, p); - } + /* current task is not kept in its runqueue in case of sched_fair class. + * Hence we need the 'on_rq?' and 'running?' tests to be separate. + */ + if (running) + p->sched_class->put_prev_task(rq, p); if (rt_prio(prio)) p->sched_class = &rt_sched_class; @@ -3999,9 +4001,9 @@ void rt_mutex_setprio(struct task_struct p->prio = prio; + if (running) + p->sched_class->set_curr_task(rq); if (on_rq) { - if (running) - p->sched_class->set_curr_task(rq); enqueue_task(rq, p, 0); inc_load(rq, p); /* @@ -4298,18 +4300,20 @@ recheck: update_rq_clock(rq); on_rq = p->se.on_rq; running = task_running(rq, p); - if (on_rq) { + if (on_rq) deactivate_task(rq, p, 0); - if (running) - p->sched_class->put_prev_task(rq, p); - } + /* current task is not kept in its runqueue in case of sched_fair class. + * Hence we need the 'on_rq?' and 'running?' tests to be separate. + */ + if (running) + p->sched_class->put_prev_task(rq, p); oldprio = p->prio; __setscheduler(rq, p, policy, param->sched_priority); + if (running) + p->sched_class->set_curr_task(rq); if (on_rq) { - if (running) - p->sched_class->set_curr_task(rq); activate_task(rq, p, 0); /* * Reschedule if we are currently running on this runqueue and @@ -7036,19 +7040,20 @@ void sched_move_task(struct task_struct running = task_running(rq, tsk); on_rq = tsk->se.on_rq; - if (on_rq) { + if (on_rq) dequeue_task(rq, tsk, 0); - if (unlikely(running)) - tsk->sched_class->put_prev_task(rq, tsk); - } + /* current task is not kept in its runqueue in case of sched_fair class. + * Hence we need the 'on_rq?' and 'running?' tests to be separate. + */ + if (unlikely(running)) + tsk->sched_class->put_prev_task(rq, tsk); set_task_cfs_rq(tsk); - if (on_rq) { - if (unlikely(running)) - tsk->sched_class->set_curr_task(rq); + if (unlikely(running)) + tsk->sched_class->set_curr_task(rq); + if (on_rq) enqueue_task(rq, tsk, 0); - } done: task_rq_unlock(rq, &flags); -- Regards, vatsa - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/