Re: overlaping printk

[Ingo Molnar]

* Ricky Beam <jfbeam@xxxxxxxxxxxxxx> wrote:

> It looks like somewhere in the path of release_console_sem() more than
> one CPU is running the log. [...]

the problem is this code in printk:

        if (oops_in_progress) {
                /* If a crash is occurring, make sure we can't deadlock */
                spin_lock_init(&logbuf_lock);
                /* And make sure that we print immediately */
                init_MUTEX(&console_sem);
        }

so two crashes on two separate CPUs can go on in parallel. The problem
is not constrained to the serial line - i've seen it on VGA too (albeit
there it's much more rare).

	Ingo
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/