[lkml]   [2002]   [Sep]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[PATCH] BUG(): sched.c: Line 944

The current in_atomic() check fails with kernel preemption enabled since
we set preempt_count to PREEMPT_ACTIVE in preempt_schedule().

We need to additionally check whether PREEMPT_ACTIVE is set.

There is also still the issue that bugging out is a bit drastic and a
hindrance to debugging; but I will tackle that later. For now, please
apply this so we can at least boot with preemption enabled.

Patch is against 2.5.35-bk.

Robert Love

diff -urN linux-2.5.35/kernel/sched.c linux/kernel/sched.c
--- linux-2.5.35/kernel/sched.c Sun Sep 15 22:18:24 2002
+++ linux/kernel/sched.c Mon Sep 16 14:43:54 2002
@@ -940,8 +940,7 @@
struct list_head *queue;
int idx;

- if (unlikely(in_atomic()))
- BUG();
+ BUG_ON(in_atomic() && preempt_count() != PREEMPT_ACTIVE);

@@ -959,7 +958,7 @@
* if entering off of a kernel preemption go straight
* to picking the next task.
- if (unlikely(preempt_count() & PREEMPT_ACTIVE))
+ if (unlikely(preempt_count() == PREEMPT_ACTIVE))
goto pick_next_task;

switch (prev->state) {
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:0.085 / U:2.864 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site