3.12-stable review patch. If anyone has any objections, please let me know.
------------------ From: Thomas Pfaff <[email protected]> commit bbfe65c219c638e19f1da5adab1005b2d68ca810 upstream. In commit ee23871389 ("genirq: Set irq thread to RT priority on creation") we moved the assigment of the thread's priority from the thread's function into __setup_irq(). That function may run in user context for instance if the user opens an UART node and then driver calls requests in the ->open() callback. That user may not have CAP_SYS_NICE and so the irq thread won't run with the SCHED_OTHER policy. This patch uses sched_setscheduler_nocheck() so we omit the CAP_SYS_NICE check which is otherwise required for the SCHED_OTHER policy. [bigeasy: Rewrite the changelog] Signed-off-by: Thomas Pfaff <[email protected]> Cc: Ivo Sieben <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Sebastian Andrzej Siewior <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- kernel/irq/manage.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -956,7 +956,7 @@ __setup_irq(unsigned int irq, struct irq goto out_mput; } - sched_setscheduler(t, SCHED_FIFO, ¶m); + sched_setscheduler_nocheck(t, SCHED_FIFO, ¶m); /* * We keep the reference to the task struct even if -- 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/

