![David S. Miller](/assets/img/avatar_default.png)
Functions invoked early when booting up a cpu can't use tracing because mcount requires a valid 'current_thread_info()' and TLB mappings to be setup. The code path of sun4v_register_mondo_queues --> register_one_mondo is one such case. sun4v_register_mondo_queues already has the necessary 'notrace' annotation, but register_one_mondo does not. Normally register_one_mondo is inlined so the bug doesn't trigger, but with some config/compiler combinations, it won't be so we must properly mark it notrace. While we're here, add 'notrace' annoations to prom_printf and prom_halt so that early error handling won't have the same problem. Reported-by: Alexander Beregalov <a.beregalov@gmail.com> Reported-by: Leif Sawyer <lsawyer@gci.com> Signed-off-by: David S. Miller <davem@davemloft.net>
47 lines
1.1 KiB
C
47 lines
1.1 KiB
C
/*
|
|
* printf.c: Internal prom library printf facility.
|
|
*
|
|
* Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
|
|
* Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
|
|
* Copyright (c) 2002 Pete Zaitcev (zaitcev@yahoo.com)
|
|
*
|
|
* We used to warn all over the code: DO NOT USE prom_printf(),
|
|
* and yet people do. Anton's banking code was outputting banks
|
|
* with prom_printf for most of the 2.4 lifetime. Since an effective
|
|
* stick is not available, we deployed a carrot: an early printk
|
|
* through PROM by means of -p boot option. This ought to fix it.
|
|
* USE printk; if you need, deploy -p.
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/compiler.h>
|
|
|
|
#include <asm/openprom.h>
|
|
#include <asm/oplib.h>
|
|
|
|
static char ppbuf[1024];
|
|
|
|
void notrace prom_write(const char *buf, unsigned int n)
|
|
{
|
|
char ch;
|
|
|
|
while (n != 0) {
|
|
--n;
|
|
if ((ch = *buf++) == '\n')
|
|
prom_putchar('\r');
|
|
prom_putchar(ch);
|
|
}
|
|
}
|
|
|
|
void notrace prom_printf(const char *fmt, ...)
|
|
{
|
|
va_list args;
|
|
int i;
|
|
|
|
va_start(args, fmt);
|
|
i = vscnprintf(ppbuf, sizeof(ppbuf), fmt, args);
|
|
va_end(args);
|
|
|
|
prom_write(ppbuf, i);
|
|
}
|