linux/arch/powerpc/kernel/traps.c

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/*
* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Modified by Cort Dougan (cort@cs.nmt.edu)
* and Paul Mackerras (paulus@samba.org)
*/
/*
* This file handles the architecture-dependent parts of hardware exceptions
*/
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/prctl.h>
#include <linux/delay.h>
#include <linux/kprobes.h>
#include <linux/kexec.h>
#include <linux/backlight.h>
#include <linux/bug.h>
#include <linux/kdebug.h>
#include <asm/pgtable.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/machdep.h>
#include <asm/rtas.h>
#include <asm/pmc.h>
#ifdef CONFIG_PPC32
#include <asm/reg.h>
#endif
#ifdef CONFIG_PMAC_BACKLIGHT
#include <asm/backlight.h>
#endif
#ifdef CONFIG_PPC64
#include <asm/firmware.h>
#include <asm/processor.h>
#endif
[POWERPC] Add the use of the firmware soft-reset-nmi to kdump. With this patch, kdump uses the firmware soft-reset NMI for two purposes: 1) Initiate the kdump (take a crash dump) by issuing a soft-reset. 2) Break a CPU out of a deadlock condition that is detected during kdump processing. When a soft-reset is initiated each CPU will enter system_reset_exception() and set its corresponding bit in the global bit-array cpus_in_sr then call die(). When die() finds the CPU's bit set in cpu_in_sr crash_kexec() is called to initiate a crash dump. The first CPU to enter crash_kexec() is called the "crashing CPU". All other CPUs are "secondary CPUs". The secondary CPU's pass through to crash_kexec_secondary() and sleep. The crashing CPU waits for all CPUs to enter via soft-reset then boots the kdump kernel (see crash_soft_reset_check()) When the system crashes due to a panic or exception, crash_kexec() is called by panic() or die(). The crashing CPU sends an IPI to all other CPUs to notify them of the pending shutdown. If a CPU is in a deadlock or hung state with interrupts disabled, the IPI will not be delivered. The result being, that the kdump kernel is not booted. This problem is solved with the use of a firmware generated soft-reset. After the crashing_cpu has issued the IPI, it waits for 10 sec for all CPUs to enter crash_ipi_callback(). A CPU signifies its entry to crash_ipi_callback() by setting its corresponding bit in the cpus_in_crash bit array. After 10 sec, if one or more CPUs have not set their bit in cpus_in_crash we assume that the CPU(s) is deadlocked. The operator is then prompted to generate a soft-reset to break the deadlock. Each CPU enters the soft reset handler as described above. Two conditions must be handled at this point: 1) The system crashed because the operator generated a soft-reset. See 2) The system had crashed before the soft-reset was generated ( in the case of a Panic or oops). The first CPU to enter crash_kexec() uses the state of the kexec_lock to determine this state. If kexec_lock is already held then condition 2 is true and crash_kexec_secondary() is called, else; this CPU is flagged as the crashing CPU, the kexec_lock is acquired and crash_kexec() proceeds as described above. Each additional CPUs responding to the soft-reset will pass through crash_kexec() to kexec_secondary(). All secondary CPUs call crash_ipi_callback() readying them self's for the shutdown. When ready they clear their bit in cpus_in_sr. The crashing CPU waits in kexec_secondary() until all other CPUs have cleared their bits in cpus_in_sr. The kexec kernel boot is then started. Signed-off-by: Haren Myneni <haren@us.ibm.com> Signed-off-by: David Wilder <dwilder@us.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-23 22:29:34 +00:00
#include <asm/kexec.h>
#ifdef CONFIG_DEBUGGER
int (*__debugger)(struct pt_regs *regs);
int (*__debugger_ipi)(struct pt_regs *regs);
int (*__debugger_bpt)(struct pt_regs *regs);
int (*__debugger_sstep)(struct pt_regs *regs);
int (*__debugger_iabr_match)(struct pt_regs *regs);
int (*__debugger_dabr_match)(struct pt_regs *regs);
int (*__debugger_fault_handler)(struct pt_regs *regs);
EXPORT_SYMBOL(__debugger);
EXPORT_SYMBOL(__debugger_ipi);
EXPORT_SYMBOL(__debugger_bpt);
EXPORT_SYMBOL(__debugger_sstep);
EXPORT_SYMBOL(__debugger_iabr_match);
EXPORT_SYMBOL(__debugger_dabr_match);
EXPORT_SYMBOL(__debugger_fault_handler);
#endif
/*
* Trap & Exception support
*/
#ifdef CONFIG_PMAC_BACKLIGHT
static void pmac_backlight_unblank(void)
{
mutex_lock(&pmac_backlight_mutex);
if (pmac_backlight) {
struct backlight_properties *props;
props = &pmac_backlight->props;
props->brightness = props->max_brightness;
props->power = FB_BLANK_UNBLANK;
backlight_update_status(pmac_backlight);
}
mutex_unlock(&pmac_backlight_mutex);
}
#else
static inline void pmac_backlight_unblank(void) { }
#endif
int die(const char *str, struct pt_regs *regs, long err)
{
static struct {
spinlock_t lock;
u32 lock_owner;
int lock_owner_depth;
} die = {
.lock = __SPIN_LOCK_UNLOCKED(die.lock),
.lock_owner = -1,
.lock_owner_depth = 0
};
[POWERPC] Add the use of the firmware soft-reset-nmi to kdump. With this patch, kdump uses the firmware soft-reset NMI for two purposes: 1) Initiate the kdump (take a crash dump) by issuing a soft-reset. 2) Break a CPU out of a deadlock condition that is detected during kdump processing. When a soft-reset is initiated each CPU will enter system_reset_exception() and set its corresponding bit in the global bit-array cpus_in_sr then call die(). When die() finds the CPU's bit set in cpu_in_sr crash_kexec() is called to initiate a crash dump. The first CPU to enter crash_kexec() is called the "crashing CPU". All other CPUs are "secondary CPUs". The secondary CPU's pass through to crash_kexec_secondary() and sleep. The crashing CPU waits for all CPUs to enter via soft-reset then boots the kdump kernel (see crash_soft_reset_check()) When the system crashes due to a panic or exception, crash_kexec() is called by panic() or die(). The crashing CPU sends an IPI to all other CPUs to notify them of the pending shutdown. If a CPU is in a deadlock or hung state with interrupts disabled, the IPI will not be delivered. The result being, that the kdump kernel is not booted. This problem is solved with the use of a firmware generated soft-reset. After the crashing_cpu has issued the IPI, it waits for 10 sec for all CPUs to enter crash_ipi_callback(). A CPU signifies its entry to crash_ipi_callback() by setting its corresponding bit in the cpus_in_crash bit array. After 10 sec, if one or more CPUs have not set their bit in cpus_in_crash we assume that the CPU(s) is deadlocked. The operator is then prompted to generate a soft-reset to break the deadlock. Each CPU enters the soft reset handler as described above. Two conditions must be handled at this point: 1) The system crashed because the operator generated a soft-reset. See 2) The system had crashed before the soft-reset was generated ( in the case of a Panic or oops). The first CPU to enter crash_kexec() uses the state of the kexec_lock to determine this state. If kexec_lock is already held then condition 2 is true and crash_kexec_secondary() is called, else; this CPU is flagged as the crashing CPU, the kexec_lock is acquired and crash_kexec() proceeds as described above. Each additional CPUs responding to the soft-reset will pass through crash_kexec() to kexec_secondary(). All secondary CPUs call crash_ipi_callback() readying them self's for the shutdown. When ready they clear their bit in cpus_in_sr. The crashing CPU waits in kexec_secondary() until all other CPUs have cleared their bits in cpus_in_sr. The kexec kernel boot is then started. Signed-off-by: Haren Myneni <haren@us.ibm.com> Signed-off-by: David Wilder <dwilder@us.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-23 22:29:34 +00:00
static int die_counter;
unsigned long flags;
if (debugger(regs))
return 1;
oops_enter();
if (die.lock_owner != raw_smp_processor_id()) {
console_verbose();
spin_lock_irqsave(&die.lock, flags);
die.lock_owner = smp_processor_id();
die.lock_owner_depth = 0;
bust_spinlocks(1);
if (machine_is(powermac))
pmac_backlight_unblank();
} else {
local_save_flags(flags);
}
if (++die.lock_owner_depth < 3) {
printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
#ifdef CONFIG_PREEMPT
printk("PREEMPT ");
#endif
#ifdef CONFIG_SMP
printk("SMP NR_CPUS=%d ", NR_CPUS);
#endif
#ifdef CONFIG_DEBUG_PAGEALLOC
printk("DEBUG_PAGEALLOC ");
#endif
#ifdef CONFIG_NUMA
printk("NUMA ");
#endif
printk("%s\n", ppc_md.name ? ppc_md.name : "");
print_modules();
show_regs(regs);
} else {
printk("Recursive die() failure, output suppressed\n");
}
bust_spinlocks(0);
die.lock_owner = -1;
add_taint(TAINT_DIE);
spin_unlock_irqrestore(&die.lock, flags);
[POWERPC] Add the use of the firmware soft-reset-nmi to kdump. With this patch, kdump uses the firmware soft-reset NMI for two purposes: 1) Initiate the kdump (take a crash dump) by issuing a soft-reset. 2) Break a CPU out of a deadlock condition that is detected during kdump processing. When a soft-reset is initiated each CPU will enter system_reset_exception() and set its corresponding bit in the global bit-array cpus_in_sr then call die(). When die() finds the CPU's bit set in cpu_in_sr crash_kexec() is called to initiate a crash dump. The first CPU to enter crash_kexec() is called the "crashing CPU". All other CPUs are "secondary CPUs". The secondary CPU's pass through to crash_kexec_secondary() and sleep. The crashing CPU waits for all CPUs to enter via soft-reset then boots the kdump kernel (see crash_soft_reset_check()) When the system crashes due to a panic or exception, crash_kexec() is called by panic() or die(). The crashing CPU sends an IPI to all other CPUs to notify them of the pending shutdown. If a CPU is in a deadlock or hung state with interrupts disabled, the IPI will not be delivered. The result being, that the kdump kernel is not booted. This problem is solved with the use of a firmware generated soft-reset. After the crashing_cpu has issued the IPI, it waits for 10 sec for all CPUs to enter crash_ipi_callback(). A CPU signifies its entry to crash_ipi_callback() by setting its corresponding bit in the cpus_in_crash bit array. After 10 sec, if one or more CPUs have not set their bit in cpus_in_crash we assume that the CPU(s) is deadlocked. The operator is then prompted to generate a soft-reset to break the deadlock. Each CPU enters the soft reset handler as described above. Two conditions must be handled at this point: 1) The system crashed because the operator generated a soft-reset. See 2) The system had crashed before the soft-reset was generated ( in the case of a Panic or oops). The first CPU to enter crash_kexec() uses the state of the kexec_lock to determine this state. If kexec_lock is already held then condition 2 is true and crash_kexec_secondary() is called, else; this CPU is flagged as the crashing CPU, the kexec_lock is acquired and crash_kexec() proceeds as described above. Each additional CPUs responding to the soft-reset will pass through crash_kexec() to kexec_secondary(). All secondary CPUs call crash_ipi_callback() readying them self's for the shutdown. When ready they clear their bit in cpus_in_sr. The crashing CPU waits in kexec_secondary() until all other CPUs have cleared their bits in cpus_in_sr. The kexec kernel boot is then started. Signed-off-by: Haren Myneni <haren@us.ibm.com> Signed-off-by: David Wilder <dwilder@us.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-23 22:29:34 +00:00
if (kexec_should_crash(current) ||
kexec_sr_activated(smp_processor_id()))
crash_kexec(regs);
[POWERPC] Add the use of the firmware soft-reset-nmi to kdump. With this patch, kdump uses the firmware soft-reset NMI for two purposes: 1) Initiate the kdump (take a crash dump) by issuing a soft-reset. 2) Break a CPU out of a deadlock condition that is detected during kdump processing. When a soft-reset is initiated each CPU will enter system_reset_exception() and set its corresponding bit in the global bit-array cpus_in_sr then call die(). When die() finds the CPU's bit set in cpu_in_sr crash_kexec() is called to initiate a crash dump. The first CPU to enter crash_kexec() is called the "crashing CPU". All other CPUs are "secondary CPUs". The secondary CPU's pass through to crash_kexec_secondary() and sleep. The crashing CPU waits for all CPUs to enter via soft-reset then boots the kdump kernel (see crash_soft_reset_check()) When the system crashes due to a panic or exception, crash_kexec() is called by panic() or die(). The crashing CPU sends an IPI to all other CPUs to notify them of the pending shutdown. If a CPU is in a deadlock or hung state with interrupts disabled, the IPI will not be delivered. The result being, that the kdump kernel is not booted. This problem is solved with the use of a firmware generated soft-reset. After the crashing_cpu has issued the IPI, it waits for 10 sec for all CPUs to enter crash_ipi_callback(). A CPU signifies its entry to crash_ipi_callback() by setting its corresponding bit in the cpus_in_crash bit array. After 10 sec, if one or more CPUs have not set their bit in cpus_in_crash we assume that the CPU(s) is deadlocked. The operator is then prompted to generate a soft-reset to break the deadlock. Each CPU enters the soft reset handler as described above. Two conditions must be handled at this point: 1) The system crashed because the operator generated a soft-reset. See 2) The system had crashed before the soft-reset was generated ( in the case of a Panic or oops). The first CPU to enter crash_kexec() uses the state of the kexec_lock to determine this state. If kexec_lock is already held then condition 2 is true and crash_kexec_secondary() is called, else; this CPU is flagged as the crashing CPU, the kexec_lock is acquired and crash_kexec() proceeds as described above. Each additional CPUs responding to the soft-reset will pass through crash_kexec() to kexec_secondary(). All secondary CPUs call crash_ipi_callback() readying them self's for the shutdown. When ready they clear their bit in cpus_in_sr. The crashing CPU waits in kexec_secondary() until all other CPUs have cleared their bits in cpus_in_sr. The kexec kernel boot is then started. Signed-off-by: Haren Myneni <haren@us.ibm.com> Signed-off-by: David Wilder <dwilder@us.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-23 22:29:34 +00:00
crash_kexec_secondary(regs);
if (in_interrupt())
panic("Fatal exception in interrupt");
if (panic_on_oops)
panic("Fatal exception");
oops_exit();
do_exit(err);
return 0;
}
void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
{
siginfo_t info;
const char fmt32[] = KERN_INFO "%s[%d]: unhandled signal %d " \
"at %08lx nip %08lx lr %08lx code %x\n";
const char fmt64[] = KERN_INFO "%s[%d]: unhandled signal %d " \
"at %016lx nip %016lx lr %016lx code %x\n";
if (!user_mode(regs)) {
if (die("Exception in kernel mode", regs, signr))
return;
} else if (show_unhandled_signals &&
unhandled_signal(current, signr) &&
printk_ratelimit()) {
printk(regs->msr & MSR_SF ? fmt64 : fmt32,
current->comm, current->pid, signr,
addr, regs->nip, regs->link, code);
}
memset(&info, 0, sizeof(info));
info.si_signo = signr;
info.si_code = code;
info.si_addr = (void __user *) addr;
force_sig_info(signr, &info, current);
/*
* Init gets no signals that it doesn't have a handler for.
* That's all very well, but if it has caused a synchronous
* exception and we ignore the resulting signal, it will just
* generate the same exception over and over again and we get
* nowhere. Better to kill it and let the kernel panic.
*/
pid namespaces: define is_global_init() and is_container_init() is_init() is an ambiguous name for the pid==1 check. Split it into is_global_init() and is_container_init(). A cgroup init has it's tsk->pid == 1. A global init also has it's tsk->pid == 1 and it's active pid namespace is the init_pid_ns. But rather than check the active pid namespace, compare the task structure with 'init_pid_ns.child_reaper', which is initialized during boot to the /sbin/init process and never changes. Changelog: 2.6.22-rc4-mm2-pidns1: - Use 'init_pid_ns.child_reaper' to determine if a given task is the global init (/sbin/init) process. This would improve performance and remove dependence on the task_pid(). 2.6.21-mm2-pidns2: - [Sukadev Bhattiprolu] Changed is_container_init() calls in {powerpc, ppc,avr32}/traps.c for the _exception() call to is_global_init(). This way, we kill only the cgroup if the cgroup's init has a bug rather than force a kernel panic. [akpm@linux-foundation.org: fix comment] [sukadev@us.ibm.com: Use is_global_init() in arch/m32r/mm/fault.c] [bunk@stusta.de: kernel/pid.c: remove unused exports] [sukadev@us.ibm.com: Fix capability.c to work with threaded init] Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Acked-by: Pavel Emelianov <xemul@openvz.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Herbert Poetzel <herbert@13thfloor.at> Cc: Kirill Korotaev <dev@sw.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 06:39:52 +00:00
if (is_global_init(current)) {
__sighandler_t handler;
spin_lock_irq(&current->sighand->siglock);
handler = current->sighand->action[signr-1].sa.sa_handler;
spin_unlock_irq(&current->sighand->siglock);
if (handler == SIG_DFL) {
/* init has generated a synchronous exception
and it doesn't have a handler for the signal */
printk(KERN_CRIT "init has generated signal %d "
"but has no handler for it\n", signr);
do_exit(signr);
}
}
}
#ifdef CONFIG_PPC64
void system_reset_exception(struct pt_regs *regs)
{
/* See if any machine dependent calls */
if (ppc_md.system_reset_exception) {
if (ppc_md.system_reset_exception(regs))
return;
}
[POWERPC] Add the use of the firmware soft-reset-nmi to kdump. With this patch, kdump uses the firmware soft-reset NMI for two purposes: 1) Initiate the kdump (take a crash dump) by issuing a soft-reset. 2) Break a CPU out of a deadlock condition that is detected during kdump processing. When a soft-reset is initiated each CPU will enter system_reset_exception() and set its corresponding bit in the global bit-array cpus_in_sr then call die(). When die() finds the CPU's bit set in cpu_in_sr crash_kexec() is called to initiate a crash dump. The first CPU to enter crash_kexec() is called the "crashing CPU". All other CPUs are "secondary CPUs". The secondary CPU's pass through to crash_kexec_secondary() and sleep. The crashing CPU waits for all CPUs to enter via soft-reset then boots the kdump kernel (see crash_soft_reset_check()) When the system crashes due to a panic or exception, crash_kexec() is called by panic() or die(). The crashing CPU sends an IPI to all other CPUs to notify them of the pending shutdown. If a CPU is in a deadlock or hung state with interrupts disabled, the IPI will not be delivered. The result being, that the kdump kernel is not booted. This problem is solved with the use of a firmware generated soft-reset. After the crashing_cpu has issued the IPI, it waits for 10 sec for all CPUs to enter crash_ipi_callback(). A CPU signifies its entry to crash_ipi_callback() by setting its corresponding bit in the cpus_in_crash bit array. After 10 sec, if one or more CPUs have not set their bit in cpus_in_crash we assume that the CPU(s) is deadlocked. The operator is then prompted to generate a soft-reset to break the deadlock. Each CPU enters the soft reset handler as described above. Two conditions must be handled at this point: 1) The system crashed because the operator generated a soft-reset. See 2) The system had crashed before the soft-reset was generated ( in the case of a Panic or oops). The first CPU to enter crash_kexec() uses the state of the kexec_lock to determine this state. If kexec_lock is already held then condition 2 is true and crash_kexec_secondary() is called, else; this CPU is flagged as the crashing CPU, the kexec_lock is acquired and crash_kexec() proceeds as described above. Each additional CPUs responding to the soft-reset will pass through crash_kexec() to kexec_secondary(). All secondary CPUs call crash_ipi_callback() readying them self's for the shutdown. When ready they clear their bit in cpus_in_sr. The crashing CPU waits in kexec_secondary() until all other CPUs have cleared their bits in cpus_in_sr. The kexec kernel boot is then started. Signed-off-by: Haren Myneni <haren@us.ibm.com> Signed-off-by: David Wilder <dwilder@us.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-23 22:29:34 +00:00
#ifdef CONFIG_KEXEC
cpu_set(smp_processor_id(), cpus_in_sr);
#endif
die("System Reset", regs, SIGABRT);
/*
* Some CPUs when released from the debugger will execute this path.
* These CPUs entered the debugger via a soft-reset. If the CPU was
* hung before entering the debugger it will return to the hung
* state when exiting this function. This causes a problem in
* kdump since the hung CPU(s) will not respond to the IPI sent
* from kdump. To prevent the problem we call crash_kexec_secondary()
* here. If a kdump had not been initiated or we exit the debugger
* with the "exit and recover" command (x) crash_kexec_secondary()
* will return after 5ms and the CPU returns to its previous state.
*/
crash_kexec_secondary(regs);
/* Must die if the interrupt is not recoverable */
if (!(regs->msr & MSR_RI))
panic("Unrecoverable System Reset");
/* What should we do here? We could issue a shutdown or hard reset. */
}
#endif
/*
* I/O accesses can cause machine checks on powermacs.
* Check if the NIP corresponds to the address of a sync
* instruction for which there is an entry in the exception
* table.
* Note that the 601 only takes a machine check on TEA
* (transfer error ack) signal assertion, and does not
* set any of the top 16 bits of SRR1.
* -- paulus.
*/
static inline int check_io_access(struct pt_regs *regs)
{
#ifdef CONFIG_PPC32
unsigned long msr = regs->msr;
const struct exception_table_entry *entry;
unsigned int *nip = (unsigned int *)regs->nip;
if (((msr & 0xffff0000) == 0 || (msr & (0x80000 | 0x40000)))
&& (entry = search_exception_tables(regs->nip)) != NULL) {
/*
* Check that it's a sync instruction, or somewhere
* in the twi; isync; nop sequence that inb/inw/inl uses.
* As the address is in the exception table
* we should be able to read the instr there.
* For the debug message, we look at the preceding
* load or store.
*/
if (*nip == 0x60000000) /* nop */
nip -= 2;
else if (*nip == 0x4c00012c) /* isync */
--nip;
if (*nip == 0x7c0004ac || (*nip >> 26) == 3) {
/* sync or twi */
unsigned int rb;
--nip;
rb = (*nip >> 11) & 0x1f;
printk(KERN_DEBUG "%s bad port %lx at %p\n",
(*nip & 0x100)? "OUT to": "IN from",
regs->gpr[rb] - _IO_BASE, nip);
regs->msr |= MSR_RI;
regs->nip = entry->fixup;
return 1;
}
}
#endif /* CONFIG_PPC32 */
return 0;
}
#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
/* On 4xx, the reason for the machine check or program exception
is in the ESR. */
#define get_reason(regs) ((regs)->dsisr)
#ifndef CONFIG_FSL_BOOKE
#define get_mc_reason(regs) ((regs)->dsisr)
#else
#define get_mc_reason(regs) (mfspr(SPRN_MCSR) & MCSR_MASK)
#endif
#define REASON_FP ESR_FP
#define REASON_ILLEGAL (ESR_PIL | ESR_PUO)
#define REASON_PRIVILEGED ESR_PPR
#define REASON_TRAP ESR_PTR
/* single-step stuff */
#define single_stepping(regs) (current->thread.dbcr0 & DBCR0_IC)
#define clear_single_step(regs) (current->thread.dbcr0 &= ~DBCR0_IC)
#else
/* On non-4xx, the reason for the machine check or program
exception is in the MSR. */
#define get_reason(regs) ((regs)->msr)
#define get_mc_reason(regs) ((regs)->msr)
#define REASON_FP 0x100000
#define REASON_ILLEGAL 0x80000
#define REASON_PRIVILEGED 0x40000
#define REASON_TRAP 0x20000
#define single_stepping(regs) ((regs)->msr & MSR_SE)
#define clear_single_step(regs) ((regs)->msr &= ~MSR_SE)
#endif
static int generic_machine_check_exception(struct pt_regs *regs)
{
unsigned long reason = get_mc_reason(regs);
#if defined(CONFIG_4xx) && !defined(CONFIG_440A)
if (reason & ESR_IMCP) {
printk("Instruction");
mtspr(SPRN_ESR, reason & ~ESR_IMCP);
} else
printk("Data");
printk(" machine check in kernel mode.\n");
#elif defined(CONFIG_440A)
printk("Machine check in kernel mode.\n");
if (reason & ESR_IMCP){
printk("Instruction Synchronous Machine Check exception\n");
mtspr(SPRN_ESR, reason & ~ESR_IMCP);
}
else {
u32 mcsr = mfspr(SPRN_MCSR);
if (mcsr & MCSR_IB)
printk("Instruction Read PLB Error\n");
if (mcsr & MCSR_DRB)
printk("Data Read PLB Error\n");
if (mcsr & MCSR_DWB)
printk("Data Write PLB Error\n");
if (mcsr & MCSR_TLBP)
printk("TLB Parity Error\n");
if (mcsr & MCSR_ICP){
flush_instruction_cache();
printk("I-Cache Parity Error\n");
}
if (mcsr & MCSR_DCSP)
printk("D-Cache Search Parity Error\n");
if (mcsr & MCSR_DCFP)
printk("D-Cache Flush Parity Error\n");
if (mcsr & MCSR_IMPE)
printk("Machine Check exception is imprecise\n");
/* Clear MCSR */
mtspr(SPRN_MCSR, mcsr);
}
#elif defined (CONFIG_E500)
printk("Machine check in kernel mode.\n");
printk("Caused by (from MCSR=%lx): ", reason);
if (reason & MCSR_MCP)
printk("Machine Check Signal\n");
if (reason & MCSR_ICPERR)
printk("Instruction Cache Parity Error\n");
if (reason & MCSR_DCP_PERR)
printk("Data Cache Push Parity Error\n");
if (reason & MCSR_DCPERR)
printk("Data Cache Parity Error\n");
if (reason & MCSR_BUS_IAERR)
printk("Bus - Instruction Address Error\n");
if (reason & MCSR_BUS_RAERR)
printk("Bus - Read Address Error\n");
if (reason & MCSR_BUS_WAERR)
printk("Bus - Write Address Error\n");
if (reason & MCSR_BUS_IBERR)
printk("Bus - Instruction Data Error\n");
if (reason & MCSR_BUS_RBERR)
printk("Bus - Read Data Bus Error\n");
if (reason & MCSR_BUS_WBERR)
printk("Bus - Read Data Bus Error\n");
if (reason & MCSR_BUS_IPERR)
printk("Bus - Instruction Parity Error\n");
if (reason & MCSR_BUS_RPERR)
printk("Bus - Read Parity Error\n");
#elif defined (CONFIG_E200)
printk("Machine check in kernel mode.\n");
printk("Caused by (from MCSR=%lx): ", reason);
if (reason & MCSR_MCP)
printk("Machine Check Signal\n");
if (reason & MCSR_CP_PERR)
printk("Cache Push Parity Error\n");
if (reason & MCSR_CPERR)
printk("Cache Parity Error\n");
if (reason & MCSR_EXCP_ERR)
printk("ISI, ITLB, or Bus Error on first instruction fetch for an exception handler\n");
if (reason & MCSR_BUS_IRERR)
printk("Bus - Read Bus Error on instruction fetch\n");
if (reason & MCSR_BUS_DRERR)
printk("Bus - Read Bus Error on data load\n");
if (reason & MCSR_BUS_WRERR)
printk("Bus - Write Bus Error on buffered store or cache line push\n");
#else /* !CONFIG_4xx && !CONFIG_E500 && !CONFIG_E200 */
printk("Machine check in kernel mode.\n");
printk("Caused by (from SRR1=%lx): ", reason);
switch (reason & 0x601F0000) {
case 0x80000:
printk("Machine check signal\n");
break;
case 0: /* for 601 */
case 0x40000:
case 0x140000: /* 7450 MSS error and TEA */
printk("Transfer error ack signal\n");
break;
case 0x20000:
printk("Data parity error signal\n");
break;
case 0x10000:
printk("Address parity error signal\n");
break;
case 0x20000000:
printk("L1 Data Cache error\n");
break;
case 0x40000000:
printk("L1 Instruction Cache error\n");
break;
case 0x00100000:
printk("L2 data cache parity error\n");
break;
default:
printk("Unknown values in msr\n");
}
#endif /* CONFIG_4xx */
return 0;
}
void machine_check_exception(struct pt_regs *regs)
{
int recover = 0;
/* See if any machine dependent calls */
if (ppc_md.machine_check_exception)
recover = ppc_md.machine_check_exception(regs);
else
recover = generic_machine_check_exception(regs);
if (recover)
return;
if (user_mode(regs)) {
regs->msr |= MSR_RI;
_exception(SIGBUS, regs, BUS_ADRERR, regs->nip);
return;
}
#if defined(CONFIG_8xx) && defined(CONFIG_PCI)
/* the qspan pci read routines can cause machine checks -- Cort */
bad_page_fault(regs, regs->dar, SIGBUS);
return;
#endif
if (debugger_fault_handler(regs)) {
regs->msr |= MSR_RI;
return;
}
if (check_io_access(regs))
return;
if (debugger_fault_handler(regs))
return;
die("Machine check", regs, SIGBUS);
/* Must die if the interrupt is not recoverable */
if (!(regs->msr & MSR_RI))
panic("Unrecoverable Machine check");
}
void SMIException(struct pt_regs *regs)
{
die("System Management Interrupt", regs, SIGABRT);
}
void unknown_exception(struct pt_regs *regs)
{
printk("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
regs->nip, regs->msr, regs->trap);
_exception(SIGTRAP, regs, 0, 0);
}
void instruction_breakpoint_exception(struct pt_regs *regs)
{
if (notify_die(DIE_IABR_MATCH, "iabr_match", regs, 5,
5, SIGTRAP) == NOTIFY_STOP)
return;
if (debugger_iabr_match(regs))
return;
_exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip);
}
void RunModeException(struct pt_regs *regs)
{
_exception(SIGTRAP, regs, 0, 0);
}
void __kprobes single_step_exception(struct pt_regs *regs)
{
regs->msr &= ~(MSR_SE | MSR_BE); /* Turn off 'trace' bits */
if (notify_die(DIE_SSTEP, "single_step", regs, 5,
5, SIGTRAP) == NOTIFY_STOP)
return;
if (debugger_sstep(regs))
return;
_exception(SIGTRAP, regs, TRAP_TRACE, regs->nip);
}
/*
* After we have successfully emulated an instruction, we have to
* check if the instruction was being single-stepped, and if so,
* pretend we got a single-step exception. This was pointed out
* by Kumar Gala. -- paulus
*/
static void emulate_single_step(struct pt_regs *regs)
{
if (single_stepping(regs)) {
clear_single_step(regs);
_exception(SIGTRAP, regs, TRAP_TRACE, 0);
}
}
static inline int __parse_fpscr(unsigned long fpscr)
{
int ret = 0;
/* Invalid operation */
if ((fpscr & FPSCR_VE) && (fpscr & FPSCR_VX))
ret = FPE_FLTINV;
/* Overflow */
else if ((fpscr & FPSCR_OE) && (fpscr & FPSCR_OX))
ret = FPE_FLTOVF;
/* Underflow */
else if ((fpscr & FPSCR_UE) && (fpscr & FPSCR_UX))
ret = FPE_FLTUND;
/* Divide by zero */
else if ((fpscr & FPSCR_ZE) && (fpscr & FPSCR_ZX))
ret = FPE_FLTDIV;
/* Inexact result */
else if ((fpscr & FPSCR_XE) && (fpscr & FPSCR_XX))
ret = FPE_FLTRES;
return ret;
}
static void parse_fpe(struct pt_regs *regs)
{
int code = 0;
flush_fp_to_thread(current);
code = __parse_fpscr(current->thread.fpscr.val);
_exception(SIGFPE, regs, code, regs->nip);
}
/*
* Illegal instruction emulation support. Originally written to
* provide the PVR to user applications using the mfspr rd, PVR.
* Return non-zero if we can't emulate, or -EFAULT if the associated
* memory access caused an access fault. Return zero on success.
*
* There are a couple of ways to do this, either "decode" the instruction
* or directly match lots of bits. In this case, matching lots of
* bits is faster and easier.
*
*/
#define INST_MFSPR_PVR 0x7c1f42a6
#define INST_MFSPR_PVR_MASK 0xfc1fffff
#define INST_DCBA 0x7c0005ec
#define INST_DCBA_MASK 0xfc0007fe
#define INST_MCRXR 0x7c000400
#define INST_MCRXR_MASK 0xfc0007fe
#define INST_STRING 0x7c00042a
#define INST_STRING_MASK 0xfc0007fe
#define INST_STRING_GEN_MASK 0xfc00067e
#define INST_LSWI 0x7c0004aa
#define INST_LSWX 0x7c00042a
#define INST_STSWI 0x7c0005aa
#define INST_STSWX 0x7c00052a
#define INST_POPCNTB 0x7c0000f4
#define INST_POPCNTB_MASK 0xfc0007fe
static int emulate_string_inst(struct pt_regs *regs, u32 instword)
{
u8 rT = (instword >> 21) & 0x1f;
u8 rA = (instword >> 16) & 0x1f;
u8 NB_RB = (instword >> 11) & 0x1f;
u32 num_bytes;
unsigned long EA;
int pos = 0;
/* Early out if we are an invalid form of lswx */
if ((instword & INST_STRING_MASK) == INST_LSWX)
if ((rT == rA) || (rT == NB_RB))
return -EINVAL;
EA = (rA == 0) ? 0 : regs->gpr[rA];
switch (instword & INST_STRING_MASK) {
case INST_LSWX:
case INST_STSWX:
EA += NB_RB;
num_bytes = regs->xer & 0x7f;
break;
case INST_LSWI:
case INST_STSWI:
num_bytes = (NB_RB == 0) ? 32 : NB_RB;
break;
default:
return -EINVAL;
}
while (num_bytes != 0)
{
u8 val;
u32 shift = 8 * (3 - (pos & 0x3));
switch ((instword & INST_STRING_MASK)) {
case INST_LSWX:
case INST_LSWI:
if (get_user(val, (u8 __user *)EA))
return -EFAULT;
/* first time updating this reg,
* zero it out */
if (pos == 0)
regs->gpr[rT] = 0;
regs->gpr[rT] |= val << shift;
break;
case INST_STSWI:
case INST_STSWX:
val = regs->gpr[rT] >> shift;
if (put_user(val, (u8 __user *)EA))
return -EFAULT;
break;
}
/* move EA to next address */
EA += 1;
num_bytes--;
/* manage our position within the register */
if (++pos == 4) {
pos = 0;
if (++rT == 32)
rT = 0;
}
}
return 0;
}
static int emulate_popcntb_inst(struct pt_regs *regs, u32 instword)
{
u32 ra,rs;
unsigned long tmp;
ra = (instword >> 16) & 0x1f;
rs = (instword >> 21) & 0x1f;
tmp = regs->gpr[rs];
tmp = tmp - ((tmp >> 1) & 0x5555555555555555ULL);
tmp = (tmp & 0x3333333333333333ULL) + ((tmp >> 2) & 0x3333333333333333ULL);
tmp = (tmp + (tmp >> 4)) & 0x0f0f0f0f0f0f0f0fULL;
regs->gpr[ra] = tmp;
return 0;
}
static int emulate_instruction(struct pt_regs *regs)
{
u32 instword;
u32 rd;
if (!user_mode(regs) || (regs->msr & MSR_LE))
return -EINVAL;
CHECK_FULL_REGS(regs);
if (get_user(instword, (u32 __user *)(regs->nip)))
return -EFAULT;
/* Emulate the mfspr rD, PVR. */
if ((instword & INST_MFSPR_PVR_MASK) == INST_MFSPR_PVR) {
rd = (instword >> 21) & 0x1f;
regs->gpr[rd] = mfspr(SPRN_PVR);
return 0;
}
/* Emulating the dcba insn is just a no-op. */
if ((instword & INST_DCBA_MASK) == INST_DCBA)
return 0;
/* Emulate the mcrxr insn. */
if ((instword & INST_MCRXR_MASK) == INST_MCRXR) {
int shift = (instword >> 21) & 0x1c;
unsigned long msk = 0xf0000000UL >> shift;
regs->ccr = (regs->ccr & ~msk) | ((regs->xer >> shift) & msk);
regs->xer &= ~0xf0000000UL;
return 0;
}
/* Emulate load/store string insn. */
if ((instword & INST_STRING_GEN_MASK) == INST_STRING)
return emulate_string_inst(regs, instword);
/* Emulate the popcntb (Population Count Bytes) instruction. */
if ((instword & INST_POPCNTB_MASK) == INST_POPCNTB) {
return emulate_popcntb_inst(regs, instword);
}
return -EINVAL;
}
int is_valid_bugaddr(unsigned long addr)
{
return is_kernel_addr(addr);
}
void __kprobes program_check_exception(struct pt_regs *regs)
{
unsigned int reason = get_reason(regs);
extern int do_mathemu(struct pt_regs *regs);
/* We can now get here via a FP Unavailable exception if the core
* has no FPU, in that case the reason flags will be 0 */
if (reason & REASON_FP) {
/* IEEE FP exception */
parse_fpe(regs);
return;
}
if (reason & REASON_TRAP) {
/* trap exception */
if (notify_die(DIE_BPT, "breakpoint", regs, 5, 5, SIGTRAP)
== NOTIFY_STOP)
return;
if (debugger_bpt(regs))
return;
if (!(regs->msr & MSR_PR) && /* not user-mode */
report_bug(regs->nip, regs) == BUG_TRAP_TYPE_WARN) {
regs->nip += 4;
return;
}
_exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip);
return;
}
local_irq_enable();
#ifdef CONFIG_MATH_EMULATION
/* (reason & REASON_ILLEGAL) would be the obvious thing here,
* but there seems to be a hardware bug on the 405GP (RevD)
* that means ESR is sometimes set incorrectly - either to
* ESR_DST (!?) or 0. In the process of chasing this with the
* hardware people - not sure if it can happen on any illegal
* instruction or only on FP instructions, whether there is a
* pattern to occurences etc. -dgibson 31/Mar/2003 */
switch (do_mathemu(regs)) {
case 0:
emulate_single_step(regs);
return;
case 1: {
int code = 0;
code = __parse_fpscr(current->thread.fpscr.val);
_exception(SIGFPE, regs, code, regs->nip);
return;
}
case -EFAULT:
_exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
return;
}
/* fall through on any other errors */
#endif /* CONFIG_MATH_EMULATION */
/* Try to emulate it if we should. */
if (reason & (REASON_ILLEGAL | REASON_PRIVILEGED)) {
switch (emulate_instruction(regs)) {
case 0:
regs->nip += 4;
emulate_single_step(regs);
return;
case -EFAULT:
_exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
return;
}
}
if (reason & REASON_PRIVILEGED)
_exception(SIGILL, regs, ILL_PRVOPC, regs->nip);
else
_exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
}
void alignment_exception(struct pt_regs *regs)
{
int sig, code, fixed = 0;
/* we don't implement logging of alignment exceptions */
if (!(current->thread.align_ctl & PR_UNALIGN_SIGBUS))
fixed = fix_alignment(regs);
if (fixed == 1) {
regs->nip += 4; /* skip over emulated instruction */
emulate_single_step(regs);
return;
}
/* Operand address was bad */
if (fixed == -EFAULT) {
sig = SIGSEGV;
code = SEGV_ACCERR;
} else {
sig = SIGBUS;
code = BUS_ADRALN;
}
if (user_mode(regs))
_exception(sig, regs, code, regs->dar);
else
bad_page_fault(regs, regs->dar, sig);
}
void StackOverflow(struct pt_regs *regs)
{
printk(KERN_CRIT "Kernel stack overflow in process %p, r1=%lx\n",
current, regs->gpr[1]);
debugger(regs);
show_regs(regs);
panic("kernel stack overflow");
}
void nonrecoverable_exception(struct pt_regs *regs)
{
printk(KERN_ERR "Non-recoverable exception at PC=%lx MSR=%lx\n",
regs->nip, regs->msr);
debugger(regs);
die("nonrecoverable exception", regs, SIGKILL);
}
void trace_syscall(struct pt_regs *regs)
{
printk("Task: %p(%d), PC: %08lX/%08lX, Syscall: %3ld, Result: %s%ld %s\n",
current, task_pid_nr(current), regs->nip, regs->link, regs->gpr[0],
regs->ccr&0x10000000?"Error=":"", regs->gpr[3], print_tainted());
}
void kernel_fp_unavailable_exception(struct pt_regs *regs)
{
printk(KERN_EMERG "Unrecoverable FP Unavailable Exception "
"%lx at %lx\n", regs->trap, regs->nip);
die("Unrecoverable FP Unavailable Exception", regs, SIGABRT);
}
void altivec_unavailable_exception(struct pt_regs *regs)
{
if (user_mode(regs)) {
/* A user program has executed an altivec instruction,
but this kernel doesn't support altivec. */
_exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
return;
}
printk(KERN_EMERG "Unrecoverable VMX/Altivec Unavailable Exception "
"%lx at %lx\n", regs->trap, regs->nip);
die("Unrecoverable VMX/Altivec Unavailable Exception", regs, SIGABRT);
}
void performance_monitor_exception(struct pt_regs *regs)
{
perf_irq(regs);
}
#ifdef CONFIG_8xx
void SoftwareEmulation(struct pt_regs *regs)
{
extern int do_mathemu(struct pt_regs *);
extern int Soft_emulate_8xx(struct pt_regs *);
#if defined(CONFIG_MATH_EMULATION) || defined(CONFIG_8XX_MINIMAL_FPEMU)
int errcode;
#endif
CHECK_FULL_REGS(regs);
if (!user_mode(regs)) {
debugger(regs);
die("Kernel Mode Software FPU Emulation", regs, SIGFPE);
}
#ifdef CONFIG_MATH_EMULATION
errcode = do_mathemu(regs);
switch (errcode) {
case 0:
emulate_single_step(regs);
return;
case 1: {
int code = 0;
code = __parse_fpscr(current->thread.fpscr.val);
_exception(SIGFPE, regs, code, regs->nip);
return;
}
case -EFAULT:
_exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
return;
default:
_exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
return;
}
#elif defined(CONFIG_8XX_MINIMAL_FPEMU)
errcode = Soft_emulate_8xx(regs);
switch (errcode) {
case 0:
emulate_single_step(regs);
return;
case 1:
_exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
return;
case -EFAULT:
_exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
return;
}
#else
_exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
#endif
}
#endif /* CONFIG_8xx */
#if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
void DebugException(struct pt_regs *regs, unsigned long debug_status)
{
if (debug_status & DBSR_IC) { /* instruction completion */
regs->msr &= ~MSR_DE;
if (user_mode(regs)) {
current->thread.dbcr0 &= ~DBCR0_IC;
} else {
/* Disable instruction completion */
mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) & ~DBCR0_IC);
/* Clear the instruction completion event */
mtspr(SPRN_DBSR, DBSR_IC);
if (debugger_sstep(regs))
return;
}
_exception(SIGTRAP, regs, TRAP_TRACE, 0);
}
}
#endif /* CONFIG_4xx || CONFIG_BOOKE */
#if !defined(CONFIG_TAU_INT)
void TAUException(struct pt_regs *regs)
{
printk("TAU trap at PC: %lx, MSR: %lx, vector=%lx %s\n",
regs->nip, regs->msr, regs->trap, print_tainted());
}
#endif /* CONFIG_INT_TAU */
#ifdef CONFIG_ALTIVEC
void altivec_assist_exception(struct pt_regs *regs)
{
int err;
if (!user_mode(regs)) {
printk(KERN_EMERG "VMX/Altivec assist exception in kernel mode"
" at %lx\n", regs->nip);
die("Kernel VMX/Altivec assist exception", regs, SIGILL);
}
flush_altivec_to_thread(current);
err = emulate_altivec(regs);
if (err == 0) {
regs->nip += 4; /* skip emulated instruction */
emulate_single_step(regs);
return;
}
if (err == -EFAULT) {
/* got an error reading the instruction */
_exception(SIGSEGV, regs, SEGV_ACCERR, regs->nip);
} else {
/* didn't recognize the instruction */
/* XXX quick hack for now: set the non-Java bit in the VSCR */
if (printk_ratelimit())
printk(KERN_ERR "Unrecognized altivec instruction "
"in %s at %lx\n", current->comm, regs->nip);
current->thread.vscr.u[3] |= 0x10000;
}
}
#endif /* CONFIG_ALTIVEC */
#ifdef CONFIG_FSL_BOOKE
void CacheLockingException(struct pt_regs *regs, unsigned long address,
unsigned long error_code)
{
/* We treat cache locking instructions from the user
* as priv ops, in the future we could try to do
* something smarter
*/
if (error_code & (ESR_DLK|ESR_ILK))
_exception(SIGILL, regs, ILL_PRVOPC, regs->nip);
return;
}
#endif /* CONFIG_FSL_BOOKE */
#ifdef CONFIG_SPE
void SPEFloatingPointException(struct pt_regs *regs)
{
unsigned long spefscr;
int fpexc_mode;
int code = 0;
spefscr = current->thread.spefscr;
fpexc_mode = current->thread.fpexc_mode;
/* Hardware does not neccessarily set sticky
* underflow/overflow/invalid flags */
if ((spefscr & SPEFSCR_FOVF) && (fpexc_mode & PR_FP_EXC_OVF)) {
code = FPE_FLTOVF;
spefscr |= SPEFSCR_FOVFS;
}
else if ((spefscr & SPEFSCR_FUNF) && (fpexc_mode & PR_FP_EXC_UND)) {
code = FPE_FLTUND;
spefscr |= SPEFSCR_FUNFS;
}
else if ((spefscr & SPEFSCR_FDBZ) && (fpexc_mode & PR_FP_EXC_DIV))
code = FPE_FLTDIV;
else if ((spefscr & SPEFSCR_FINV) && (fpexc_mode & PR_FP_EXC_INV)) {
code = FPE_FLTINV;
spefscr |= SPEFSCR_FINVS;
}
else if ((spefscr & (SPEFSCR_FG | SPEFSCR_FX)) && (fpexc_mode & PR_FP_EXC_RES))
code = FPE_FLTRES;
current->thread.spefscr = spefscr;
_exception(SIGFPE, regs, code, regs->nip);
return;
}
#endif
/*
* We enter here if we get an unrecoverable exception, that is, one
* that happened at a point where the RI (recoverable interrupt) bit
* in the MSR is 0. This indicates that SRR0/1 are live, and that
* we therefore lost state by taking this exception.
*/
void unrecoverable_exception(struct pt_regs *regs)
{
printk(KERN_EMERG "Unrecoverable exception %lx at %lx\n",
regs->trap, regs->nip);
die("Unrecoverable exception", regs, SIGABRT);
}
#ifdef CONFIG_BOOKE_WDT
/*
* Default handler for a Watchdog exception,
* spins until a reboot occurs
*/
void __attribute__ ((weak)) WatchdogHandler(struct pt_regs *regs)
{
/* Generic WatchdogHandler, implement your own */
mtspr(SPRN_TCR, mfspr(SPRN_TCR)&(~TCR_WIE));
return;
}
void WatchdogException(struct pt_regs *regs)
{
printk (KERN_EMERG "PowerPC Book-E Watchdog Exception\n");
WatchdogHandler(regs);
}
#endif
/*
* We enter here if we discover during exception entry that we are
* running in supervisor mode with a userspace value in the stack pointer.
*/
void kernel_bad_stack(struct pt_regs *regs)
{
printk(KERN_EMERG "Bad kernel stack pointer %lx at %lx\n",
regs->gpr[1], regs->nip);
die("Bad kernel stack pointer", regs, SIGABRT);
}
void __init trap_init(void)
{
}