Re: pre-empt and smp in 2.5.37 - is it supposed to work?

Robert Love
2002-09-20T20:04:17Z

On Fri, 2002-09-20 at 16:04, Jurriaan wrote:

> I get a large screen full of hex addresses even before my framebuffer
> activates, so I wonder if breakage when using preempt and smp is a known
> issue in 2.5.37 or not?

You need this yet-to-be-merged patch. It should work fine with it.

It is just an overzealous debugging test..

Robert Love

diff -urN linux-2.5.37/kernel/sched.c linux/kernel/sched.c
--- linux-2.5.37/kernel/sched.c Fri Sep 20 11:20:32 2002
+++ linux/kernel/sched.c Fri Sep 20 15:49:05 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 path 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 "bad: scheduling while atomic!\n");
+ dump_stack();
+ }
+ }

#if CONFIG_DEBUG_HIGHMEM
check_highmem_ptes();