[PATCH] Generic BUG for i386

This makes i386 use the generic BUG machinery.  There are no functional
changes from the old i386 implementation.

The main advantage in using the generic BUG machinery for i386 is that the
inlined overhead of BUG is just the ud2a instruction; the file+line(+function)
information are no longer inlined into the instruction stream.  This reduces
cache pollution, and makes disassembly work properly.

Signed-off-by: Jeremy Fitzhardinge <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Hugh Dickens <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Rusty Russell <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
Jeremy Fitzhardinge 2006-12-08 02:36:21 -08:00 • committed by Linus Torvalds
commit 91768d6c2b
6 changed files with 42 additions and 40 deletions

View file

@ -49,6 +49,11 @@ config GENERIC_IOMAP
bool
default y
config GENERIC_BUG
bool
default y
depends on BUG
config GENERIC_HWEIGHT
bool
default y

View file

@ -21,6 +21,7 @@
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/bug.h>
#if 0
#define DEBUGP printk
@ -141,10 +142,11 @@ int module_finalize(const Elf_Ehdr *hdr,
apply_paravirt(pseg, pseg + para->sh_size);
}
return 0;
return module_bug_finalize(hdr, sechdrs, me);
}
void module_arch_cleanup(struct module *mod)
{
alternatives_smp_module_del(mod);
module_bug_cleanup(mod);
}

View file

@ -30,6 +30,7 @@
#include <linux/unwind.h>
#include <linux/uaccess.h>
#include <linux/nmi.h>
#include <linux/bug.h>
#ifdef CONFIG_EISA
#include <linux/ioport.h>
@ -420,43 +421,22 @@ void show_registers(struct pt_regs *regs)
printk("\n");
}
static void handle_BUG(struct pt_regs *regs)
int is_valid_bugaddr(unsigned long eip)
{
unsigned long eip = regs->eip;
unsigned short ud2;
if (eip < PAGE_OFFSET)
return;
return 0;
if (probe_kernel_address((unsigned short *)eip, ud2))
return;
if (ud2 != 0x0b0f)
return;
return 0;
printk(KERN_EMERG "------------[ cut here ]------------\n");
#ifdef CONFIG_DEBUG_BUGVERBOSE
do {
unsigned short line;
char *file;
char c;
if (probe_kernel_address((unsigned short *)(eip + 2), line))
break;
if (probe_kernel_address((char **)(eip + 4), file) ||
(unsigned long)file < PAGE_OFFSET ||
probe_kernel_address(file, c))
file = "<bad filename>";
printk(KERN_EMERG "kernel BUG at %s:%d!\n", file, line);
return;
} while (0);
#endif
printk(KERN_EMERG "Kernel BUG at [verbose debug info unavailable]\n");
return ud2 == 0x0b0f;
}
/* This is gone through when something in the kernel
* has done something bad and is about to be terminated.
*/
/*
* This is gone through when something in the kernel has done something bad and
* is about to be terminated.
*/
void die(const char * str, struct pt_regs * regs, long err)
{
static struct {
@ -488,7 +468,8 @@ void die(const char * str, struct pt_regs * regs, long err)
unsigned long esp;
unsigned short ss;
handle_BUG(regs);
report_bug(regs->eip);
printk(KERN_EMERG "%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
#ifdef CONFIG_PREEMPT
printk(KERN_EMERG "PREEMPT ");

View file

@ -57,6 +57,8 @@ SECTIONS
RODATA
BUG_TABLE
. = ALIGN(4);
.tracedata : AT(ADDR(.tracedata) - LOAD_OFFSET) {
__tracedata_start = .;