Re: [PATCH] 2.4.16 kernel/printk.c (per processorinitializationcheck)

[David Mosberger]

>>>>> On Sun, 9 Dec 2001 00:55:25 +0000 (GMT), Alan Cox <[e-mail]> said:

  >> I don't think you can do it early enough.  calibrate_delay()
  >> requires irqs to be enabled and the first printk() happens long
  >> before irqs are enabled on an AP.

  Alan> So we make sure our initial console code doesnt need udelay(),
  Alan> or set an initial safe default like 25MHz

So someone is going to maintain a list of what a console driver can
and cannot do for all 12+ ports in existence?

The alternative is to do:

--- linux-2.4.16/kernel/printk.c	Mon Nov 26 11:19:24 2001
+++ lia64-kdb/kernel/printk.c	Thu Nov 29 21:45:08 2001
@@ -498,6 +505,10 @@
 	for ( ; ; ) {
 		spin_lock_irqsave(&logbuf_lock, flags);
 		must_wake_klogd |= log_start - log_end;
+#ifdef CONFIG_SMP
+		if (!(cpu_online_map & (1UL << smp_processor_id())))
+			break;
+#endif
 		if (con_start == log_end)
 			break;			/* Nothing to print */
 		_con_start = con_start;

and be done with it.

	--david