Re: [PATCH] schedule() in_atomic() fix

[Robert Love <rml@tech9.net>]

On Wed, 2002-09-18 at 00:46, Robert Love wrote:

> Attached patch fixes the scheduler in_atomic() problem with kernel
> preemption enabled (and is also working - when kernel preemption is on,
> it finds a couple issues during boot).

Attached version works with non-CONFIG_PREEMPT ...

	Robert Love

diff -urN linux-2.5.36/kernel/sched.c linux/kernel/sched.c
--- linux-2.5.36/kernel/sched.c	Tue Sep 17 20:58:48 2002
+++ linux/kernel/sched.c	Wed Sep 18 11:03:44 2002
@@ -940,8 +940,17 @@
 	struct list_head *queue;
 	int idx;
 
-	if (unlikely(in_atomic()))
-		BUG();
+	/*
+	 * Test if we are atomic.  Since do_exit() needs to call into
+	 * schedule() atomically, we ignore that for now.  Otherwise,
+	 * whine if we are scheduling when we should not be.
+	 */
+	if (likely(current->state != TASK_ZOMBIE)) {
+		if (unlikely(in_atomic())) {
+			printk(KERN_ERR "scheduling while atomic!\n");
+			dump_stack();
+		}
+	}
 
 #if CONFIG_DEBUG_HIGHMEM
 	check_highmem_ptes();