linux_dsm_epyc7002/arch/sh/kernel/machvec.c
Paul Mundt 5556410e22 sh: panic on machvec section misalignment.
Now that __initmv references the machvec section unconditionally
there have been cases where folks have been mistakenly flagging
non-machvec structures with the machvec section attribute (presumably
to shut up modpost). This leads to obscure breakage in earlyprintk
amongst other places and is rather non-obvious.

Add a simple sanity check to try and catch __initmv misuse and
panic early.

Reported-by: Markus Brunner <super.firetwister@gmail.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-08-07 19:13:23 +09:00

138 lines
3.3 KiB
C

/*
* arch/sh/kernel/machvec.c
*
* The SuperH machine vector setup handlers, yanked from setup.c
*
* Copyright (C) 1999 Niibe Yutaka
* Copyright (C) 2002 - 2007 Paul Mundt
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/init.h>
#include <linux/string.h>
#include <asm/machvec.h>
#include <asm/sections.h>
#include <asm/io.h>
#include <asm/irq.h>
#define MV_NAME_SIZE 32
#define for_each_mv(mv) \
for ((mv) = (struct sh_machine_vector *)&__machvec_start; \
(mv) && (unsigned long)(mv) < (unsigned long)&__machvec_end; \
(mv)++)
static struct sh_machine_vector * __init get_mv_byname(const char *name)
{
struct sh_machine_vector *mv;
for_each_mv(mv)
if (strcasecmp(name, mv->mv_name) == 0)
return mv;
return NULL;
}
static unsigned int __initdata machvec_selected;
static int __init early_parse_mv(char *from)
{
char mv_name[MV_NAME_SIZE] = "";
char *mv_end;
char *mv_comma;
int mv_len;
struct sh_machine_vector *mvp;
mv_end = strchr(from, ' ');
if (mv_end == NULL)
mv_end = from + strlen(from);
mv_comma = strchr(from, ',');
mv_len = mv_end - from;
if (mv_len > (MV_NAME_SIZE-1))
mv_len = MV_NAME_SIZE-1;
memcpy(mv_name, from, mv_len);
mv_name[mv_len] = '\0';
from = mv_end;
machvec_selected = 1;
/* Boot with the generic vector */
if (strcmp(mv_name, "generic") == 0)
return 0;
mvp = get_mv_byname(mv_name);
if (unlikely(!mvp)) {
printk("Available vectors:\n\n\t'%s', ", sh_mv.mv_name);
for_each_mv(mvp)
printk("'%s', ", mvp->mv_name);
printk("\n\n");
panic("Failed to select machvec '%s' -- halting.\n",
mv_name);
} else
sh_mv = *mvp;
return 0;
}
early_param("sh_mv", early_parse_mv);
void __init sh_mv_setup(void)
{
/*
* Only overload the machvec if one hasn't been selected on
* the command line with sh_mv=
*/
if (!machvec_selected) {
unsigned long machvec_size;
machvec_size = ((unsigned long)&__machvec_end -
(unsigned long)&__machvec_start);
/*
* Sanity check for machvec section alignment. Ensure
* __initmv hasn't been misused.
*/
if (machvec_size % sizeof(struct sh_machine_vector))
panic("machvec misaligned, invalid __initmv use?");
/*
* If the machvec hasn't been preselected, use the first
* vector (usually the only one) from .machvec.init.
*/
if (machvec_size >= sizeof(struct sh_machine_vector))
sh_mv = *(struct sh_machine_vector *)&__machvec_start;
}
printk(KERN_NOTICE "Booting machvec: %s\n", get_system_type());
/*
* Manually walk the vec, fill in anything that the board hasn't yet
* by hand, wrapping to the generic implementation.
*/
#define mv_set(elem) do { \
if (!sh_mv.mv_##elem) \
sh_mv.mv_##elem = generic_##elem; \
} while (0)
mv_set(inb); mv_set(inw); mv_set(inl);
mv_set(outb); mv_set(outw); mv_set(outl);
mv_set(inb_p); mv_set(inw_p); mv_set(inl_p);
mv_set(outb_p); mv_set(outw_p); mv_set(outl_p);
mv_set(insb); mv_set(insw); mv_set(insl);
mv_set(outsb); mv_set(outsw); mv_set(outsl);
mv_set(readb); mv_set(readw); mv_set(readl);
mv_set(writeb); mv_set(writew); mv_set(writel);
mv_set(ioport_map);
mv_set(ioport_unmap);
mv_set(irq_demux);
if (!sh_mv.mv_nr_irqs)
sh_mv.mv_nr_irqs = NR_IRQS;
}