[patch 19/38] Use generic bug.

Martin Schwidefsky
2007-04-27T14:06:35Z

[-- Attachment #1: 122-bug-output.diff --]
[-- Type: text/plain, Size: 7001 bytes --]

From: Heiko Carstens <heiko.carstens@de.ibm.com>

Generic bug implementation for s390. Will increase the value of the
console output on BUG() statements since registers r0-r5,r14 will
not be clobbered by a printk() call that was previously done before
the illegal instruction of BUG() was hit.
Also implements an architecture specific WARN_ON(). Output of that
could be increased but requires common code change.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
---

arch/s390/Kconfig | 5 ++
arch/s390/defconfig | 2 +
arch/s390/kernel/module.c | 4 +-
arch/s390/kernel/traps.c | 17 ++++++++--
arch/s390/kernel/vmlinux.lds.S | 10 +++++
include/asm-s390/bug.h | 69 +++++++++++++++++++++++++++++++++--------
6 files changed, 89 insertions(+), 18 deletions(-)

Index: quilt-2.6/arch/s390/defconfig
===================================================================
--- quilt-2.6.orig/arch/s390/defconfig 2007-04-27 16:01:49.000000000 +0200
+++ quilt-2.6/arch/s390/defconfig 2007-04-27 16:04:56.000000000 +0200
@@ -12,6 +12,7 @@
# CONFIG_ARCH_HAS_ILOG2_U64 is not set
CONFIG_GENERIC_HWEIGHT=y
CONFIG_GENERIC_TIME=y
+CONFIG_GENERIC_BUG=y
CONFIG_NO_IOMEM=y
CONFIG_S390=y
CONFIG_DEFCONFIG_LIST="/lib/modules/$UNAME_RELEASE/.config"
@@ -705,6 +706,7 @@
CONFIG_DEBUG_SPINLOCK_SLEEP=y
# CONFIG_DEBUG_LOCKING_API_SELFTESTS is not set
# CONFIG_DEBUG_KOBJECT is not set
+CONFIG_DEBUG_BUGVERBOSE=y
# CONFIG_DEBUG_INFO is not set
# CONFIG_DEBUG_VM is not set
# CONFIG_DEBUG_LIST is not set
Index: quilt-2.6/arch/s390/Kconfig
===================================================================
--- quilt-2.6.orig/arch/s390/Kconfig 2007-04-27 16:01:49.000000000 +0200
+++ quilt-2.6/arch/s390/Kconfig 2007-04-27 16:04:56.000000000 +0200
@@ -41,6 +41,11 @@
config GENERIC_TIME
def_bool y

+config GENERIC_BUG
+ bool
+ depends on BUG
+ default y
+
config NO_IOMEM
def_bool y

Index: quilt-2.6/arch/s390/kernel/module.c
===================================================================
--- quilt-2.6.orig/arch/s390/kernel/module.c 2007-04-27 16:01:49.000000000 +0200
+++ quilt-2.6/arch/s390/kernel/module.c 2007-04-27 16:04:56.000000000 +0200
@@ -31,6 +31,7 @@
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/moduleloader.h>
+#include <linux/bug.h>

#if 0
#define DEBUGP printk
@@ -398,9 +399,10 @@
struct module *me)
{
vfree(me->arch.syminfo);
- return 0;
+ return module_bug_finalize(hdr, sechdrs, me);
}

void module_arch_cleanup(struct module *mod)
{
+ module_bug_cleanup(mod);
}
Index: quilt-2.6/arch/s390/kernel/traps.c
===================================================================
--- quilt-2.6.orig/arch/s390/kernel/traps.c 2007-04-27 16:04:56.000000000 +0200
+++ quilt-2.6/arch/s390/kernel/traps.c 2007-04-27 16:04:56.000000000 +0200
@@ -30,7 +30,7 @@
#include <linux/kallsyms.h>
#include <linux/reboot.h>
#include <linux/kprobes.h>
-
+#include <linux/bug.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/io.h>
@@ -297,6 +297,11 @@
#endif
}

+int is_valid_bugaddr(unsigned long addr)
+{
+ return 1;
+}
+
static void __kprobes inline do_trap(long interruption_code, int signr,
char *str, struct pt_regs *regs,
siginfo_t *info)
@@ -323,8 +328,14 @@
fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
if (fixup)
regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
- else
- die(str, regs, interruption_code);
+ else {
+ enum bug_trap_type btt;
+
+ btt = report_bug(regs->psw.addr & PSW_ADDR_INSN);
+ if (btt == BUG_TRAP_TYPE_WARN)
+ return;
+ die(str, regs, interruption_code);
+ }
}
}

Index: quilt-2.6/arch/s390/kernel/vmlinux.lds.S
===================================================================
--- quilt-2.6.orig/arch/s390/kernel/vmlinux.lds.S 2007-04-27 16:01:49.000000000 +0200
+++ quilt-2.6/arch/s390/kernel/vmlinux.lds.S 2007-04-27 16:04:56.000000000 +0200
@@ -45,6 +45,8 @@
__ex_table : { *(__ex_table) }
__stop___ex_table = .;

+ BUG_TABLE
+
.data : { /* Data */
*(.data)
CONSTRUCTORS
@@ -77,6 +79,12 @@
*(.init.text)
_einittext = .;
}
+ /*
+ * .exit.text is discarded at runtime, not link time,
+ * to deal with references from __bug_table
+ */
+ .exit.text : { *(.exit.text) }
+
.init.data : { *(.init.data) }
. = ALIGN(256);
__setup_start = .;
@@ -116,7 +124,7 @@

/* Sections to be discarded */
/DISCARD/ : {
- *(.exit.text) *(.exit.data) *(.exitcall.exit)
+ *(.exit.data) *(.exitcall.exit)
}

/* Stabs debugging sections. */
Index: quilt-2.6/include/asm-s390/bug.h
===================================================================
--- quilt-2.6.orig/include/asm-s390/bug.h 2007-04-27 16:01:49.000000000 +0200
+++ quilt-2.6/include/asm-s390/bug.h 2007-04-27 16:04:56.000000000 +0200
@@ -1,27 +1,70 @@
-#ifndef _S390_BUG_H
-#define _S390_BUG_H
+#ifndef _ASM_S390_BUG_H
+#define _ASM_S390_BUG_H

#include <linux/kernel.h>

#ifdef CONFIG_BUG

-static inline __attribute__((noreturn)) void __do_illegal_op(void)
-{
-#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 3)
- __builtin_trap();
+#ifdef CONFIG_64BIT
+#define S390_LONG ".quad"
#else
- asm volatile(".long 0");
+#define S390_LONG ".long"
#endif
-}

-#define BUG() do { \
- printk("kernel BUG at %s:%d!\n", __FILE__, __LINE__); \
- __do_illegal_op(); \
+#ifdef CONFIG_DEBUG_BUGVERBOSE
+
+#define __EMIT_BUG(x) do { \
+ asm volatile( \
+ "0: j 0b+2\n" \
+ "1:\n" \
+ ".section .rodata.str,\"aMS\",@progbits,1\n" \
+ "2: .asciz \""__FILE__"\"\n" \
+ ".previous\n" \
+ ".section __bug_table,\"a\"\n" \
+ "3:\t" S390_LONG "\t1b,2b\n" \
+ " .short %0,%1\n" \
+ " .org 3b+%2\n" \
+ ".previous\n" \
+ : : "i" (__LINE__), \
+ "i" (x), \
+ "i" (sizeof(struct bug_entry))); \
} while (0)

+#else /* CONFIG_DEBUG_BUGVERBOSE */
+
+#define __EMIT_BUG(x) do { \
+ asm volatile( \
+ "0: j 0b+2\n" \
+ "1:\n" \
+ ".section __bug_table,\"a\"\n" \
+ "2:\t" S390_LONG "\t1b\n" \
+ " .short %0\n" \
+ " .org 2b+%1\n" \
+ ".previous\n" \
+ : : "i" (x), \
+ "i" (sizeof(struct bug_entry))); \
+} while (0)
+
+#endif /* CONFIG_DEBUG_BUGVERBOSE */
+
+#define BUG() __EMIT_BUG(0)
+
+#define WARN_ON(x) ({ \
+ typeof(x) __ret_warn_on = (x); \
+ if (__builtin_constant_p(__ret_warn_on)) { \
+ if (__ret_warn_on) \
+ __EMIT_BUG(BUGFLAG_WARNING); \
+ } else { \
+ if (unlikely(__ret_warn_on)) \
+ __EMIT_BUG(BUGFLAG_WARNING); \
+ } \
+ unlikely(__ret_warn_on); \
+})
+
#define HAVE_ARCH_BUG
-#endif
+#define HAVE_ARCH_WARN_ON
+#endif /* CONFIG_BUG */

#include <asm-generic/bug.h>

-#endif
+#endif /* _ASM_S390_BUG_H */