[lkml]   [2002]   [Sep]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[PATCH] bad: schedule() with irqs disabled!
On Tue, 2002-09-03 at 09:36, Morten Helgesen wrote:

> bad: schedule() with irqs disabled!

OK, Linus, you are right... there are enough instances of this we are
not going to find them all (although I suspect Andrew's slab.c fixes
will cover most of the cases). Further, I think we can should actually
purposely call preempt_schedule() in certain cases after interrupt
reenable to check for reschedules...

Let's just make it a rule "no preemption if interrupts are off" and
enforce that.

Patch is against 2.5.33-BK, please apply.

Robert Love

diff -urN linux-2.5.33/kernel/sched.c linux/kernel/sched.c
--- linux-2.5.33/kernel/sched.c Sat Aug 31 18:04:53 2002
+++ linux/kernel/sched.c Tue Sep 3 10:48:56 2002
@@ -1032,15 +1032,12 @@
struct thread_info *ti = current_thread_info();

- if (unlikely(ti->preempt_count))
+ /*
+ * If there is a non-zero preempt_count or interrupts are disabled,
+ * we do not want to preempt the current task. Just return..
+ */
+ if (unlikely(ti->preempt_count || irqs_disabled()))
- if (unlikely(irqs_disabled())) {
- preempt_disable();
- printk("bad: schedule() with irqs disabled!\n");
- show_stack(NULL);
- preempt_enable_no_resched();
- return;
- }

ti->preempt_count = PREEMPT_ACTIVE;
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:28    [W:0.035 / U:0.220 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site