Hexagon: Provide basic debugging and system trap support.
Signed-off-by: Richard Kuo <rkuo@codeaurora.org> Signed-off-by: Linas Vepstas <linas@codeaurora.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Richard Kuo
Linus Torvalds
parent
39e89c9fc5
commit
cf9750bae2
2 changed files with 483 additions and 0 deletions
29
arch/hexagon/include/asm/traps.h
Normal file
29
arch/hexagon/include/asm/traps.h
Normal file
|
|
@ -0,0 +1,29 @@
|
||||||
|
/*
|
||||||
|
* Trap support for Hexagon
|
||||||
|
*
|
||||||
|
* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
|
||||||
|
*
|
||||||
|
* This program is free software; you can redistribute it and/or modify
|
||||||
|
* it under the terms of the GNU General Public License version 2 and
|
||||||
|
* only version 2 as published by the Free Software Foundation.
|
||||||
|
*
|
||||||
|
* This program is distributed in the hope that it will be useful,
|
||||||
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||||
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||||
|
* GNU General Public License for more details.
|
||||||
|
*
|
||||||
|
* You should have received a copy of the GNU General Public License
|
||||||
|
* along with this program; if not, write to the Free Software
|
||||||
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
|
||||||
|
* 02110-1301, USA.
|
||||||
|
*/
|
||||||
|
|
||||||
|
#ifndef _ASM_HEXAGON_TRAPS_H
|
||||||
|
#define _ASM_HEXAGON_TRAPS_H
|
||||||
|
|
||||||
|
#include <asm/registers.h>
|
||||||
|
|
||||||
|
extern int die(const char *str, struct pt_regs *regs, long err);
|
||||||
|
extern int die_if_kernel(char *str, struct pt_regs *regs, long err);
|
||||||
|
|
||||||
|
#endif /* _ASM_HEXAGON_TRAPS_H */
|
||||||
454
arch/hexagon/kernel/traps.c
Normal file
454
arch/hexagon/kernel/traps.c
Normal file
|
|
@ -0,0 +1,454 @@
|
||||||
|
/*
|
||||||
|
* Kernel traps/events for Hexagon processor
|
||||||
|
*
|
||||||
|
* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
|
||||||
|
*
|
||||||
|
* This program is free software; you can redistribute it and/or modify
|
||||||
|
* it under the terms of the GNU General Public License version 2 and
|
||||||
|
* only version 2 as published by the Free Software Foundation.
|
||||||
|
*
|
||||||
|
* This program is distributed in the hope that it will be useful,
|
||||||
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||||
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||||
|
* GNU General Public License for more details.
|
||||||
|
*
|
||||||
|
* You should have received a copy of the GNU General Public License
|
||||||
|
* along with this program; if not, write to the Free Software
|
||||||
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
|
||||||
|
* 02110-1301, USA.
|
||||||
|
*/
|
||||||
|
|
||||||
|
#include <linux/init.h>
|
||||||
|
#include <linux/sched.h>
|
||||||
|
#include <linux/module.h>
|
||||||
|
#include <linux/kallsyms.h>
|
||||||
|
#include <linux/kdebug.h>
|
||||||
|
#include <linux/syscalls.h>
|
||||||
|
#include <linux/signal.h>
|
||||||
|
#include <linux/tracehook.h>
|
||||||
|
#include <asm/traps.h>
|
||||||
|
#include <asm/vm_fault.h>
|
||||||
|
#include <asm/syscall.h>
|
||||||
|
#include <asm/registers.h>
|
||||||
|
#include <asm/unistd.h>
|
||||||
|
#include <asm/sections.h>
|
||||||
|
#ifdef CONFIG_KGDB
|
||||||
|
# include <linux/kgdb.h>
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#define TRAP_SYSCALL 1
|
||||||
|
#define TRAP_DEBUG 0xdb
|
||||||
|
|
||||||
|
void __init trap_init(void)
|
||||||
|
{
|
||||||
|
}
|
||||||
|
|
||||||
|
#ifdef CONFIG_GENERIC_BUG
|
||||||
|
/* Maybe should resemble arch/sh/kernel/traps.c ?? */
|
||||||
|
int is_valid_bugaddr(unsigned long addr)
|
||||||
|
{
|
||||||
|
return 1;
|
||||||
|
}
|
||||||
|
#endif /* CONFIG_GENERIC_BUG */
|
||||||
|
|
||||||
|
static const char *ex_name(int ex)
|
||||||
|
{
|
||||||
|
switch (ex) {
|
||||||
|
case HVM_GE_C_XPROT:
|
||||||
|
case HVM_GE_C_XUSER:
|
||||||
|
return "Execute protection fault";
|
||||||
|
case HVM_GE_C_RPROT:
|
||||||
|
case HVM_GE_C_RUSER:
|
||||||
|
return "Read protection fault";
|
||||||
|
case HVM_GE_C_WPROT:
|
||||||
|
case HVM_GE_C_WUSER:
|
||||||
|
return "Write protection fault";
|
||||||
|
case HVM_GE_C_XMAL:
|
||||||
|
return "Misaligned instruction";
|
||||||
|
case HVM_GE_C_RMAL:
|
||||||
|
return "Misaligned data load";
|
||||||
|
case HVM_GE_C_WMAL:
|
||||||
|
return "Misaligned data store";
|
||||||
|
case HVM_GE_C_INVI:
|
||||||
|
case HVM_GE_C_PRIVI:
|
||||||
|
return "Illegal instruction";
|
||||||
|
case HVM_GE_C_BUS:
|
||||||
|
return "Precise bus error";
|
||||||
|
case HVM_GE_C_CACHE:
|
||||||
|
return "Cache error";
|
||||||
|
|
||||||
|
case 0xdb:
|
||||||
|
return "Debugger trap";
|
||||||
|
|
||||||
|
default:
|
||||||
|
return "Unrecognized exception";
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
static void do_show_stack(struct task_struct *task, unsigned long *fp,
|
||||||
|
unsigned long ip)
|
||||||
|
{
|
||||||
|
int kstack_depth_to_print = 24;
|
||||||
|
unsigned long offset, size;
|
||||||
|
const char *name = NULL;
|
||||||
|
unsigned long *newfp;
|
||||||
|
unsigned long low, high;
|
||||||
|
char tmpstr[128];
|
||||||
|
char *modname;
|
||||||
|
int i;
|
||||||
|
|
||||||
|
if (task == NULL)
|
||||||
|
task = current;
|
||||||
|
|
||||||
|
printk(KERN_INFO "CPU#%d, %s/%d, Call Trace:\n",
|
||||||
|
raw_smp_processor_id(), task->comm,
|
||||||
|
task_pid_nr(task));
|
||||||
|
|
||||||
|
if (fp == NULL) {
|
||||||
|
if (task == current) {
|
||||||
|
asm("%0 = r30" : "=r" (fp));
|
||||||
|
} else {
|
||||||
|
fp = (unsigned long *)
|
||||||
|
((struct hexagon_switch_stack *)
|
||||||
|
task->thread.switch_sp)->fp;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
if ((((unsigned long) fp) & 0x3) || ((unsigned long) fp < 0x1000)) {
|
||||||
|
printk(KERN_INFO "-- Corrupt frame pointer %p\n", fp);
|
||||||
|
return;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Saved link reg is one word above FP */
|
||||||
|
if (!ip)
|
||||||
|
ip = *(fp+1);
|
||||||
|
|
||||||
|
/* Expect kernel stack to be in-bounds */
|
||||||
|
low = (unsigned long)task_stack_page(task);
|
||||||
|
high = low + THREAD_SIZE - 8;
|
||||||
|
low += sizeof(struct thread_info);
|
||||||
|
|
||||||
|
for (i = 0; i < kstack_depth_to_print; i++) {
|
||||||
|
|
||||||
|
name = kallsyms_lookup(ip, &size, &offset, &modname, tmpstr);
|
||||||
|
|
||||||
|
printk(KERN_INFO "[%p] 0x%lx: %s + 0x%lx", fp, ip, name,
|
||||||
|
offset);
|
||||||
|
if (((unsigned long) fp < low) || (high < (unsigned long) fp))
|
||||||
|
printk(KERN_CONT " (FP out of bounds!)");
|
||||||
|
if (modname)
|
||||||
|
printk(KERN_CONT " [%s] ", modname);
|
||||||
|
printk(KERN_CONT "\n");
|
||||||
|
|
||||||
|
newfp = (unsigned long *) *fp;
|
||||||
|
|
||||||
|
if (((unsigned long) newfp) & 0x3) {
|
||||||
|
printk(KERN_INFO "-- Corrupt frame pointer %p\n",
|
||||||
|
newfp);
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Attempt to continue past exception. */
|
||||||
|
if (0 == newfp) {
|
||||||
|
struct pt_regs *regs = (struct pt_regs *) (((void *)fp)
|
||||||
|
+ 8);
|
||||||
|
|
||||||
|
if (regs->syscall_nr != -1) {
|
||||||
|
printk(KERN_INFO "-- trap0 -- syscall_nr: %ld",
|
||||||
|
regs->syscall_nr);
|
||||||
|
printk(KERN_CONT " psp: %lx elr: %lx\n",
|
||||||
|
pt_psp(regs), pt_elr(regs));
|
||||||
|
break;
|
||||||
|
} else {
|
||||||
|
/* really want to see more ... */
|
||||||
|
kstack_depth_to_print += 6;
|
||||||
|
printk(KERN_INFO "-- %s (0x%lx) badva: %lx\n",
|
||||||
|
ex_name(pt_cause(regs)), pt_cause(regs),
|
||||||
|
pt_badva(regs));
|
||||||
|
}
|
||||||
|
|
||||||
|
newfp = (unsigned long *) regs->r30;
|
||||||
|
ip = pt_elr(regs);
|
||||||
|
} else {
|
||||||
|
ip = *(newfp + 1);
|
||||||
|
}
|
||||||
|
|
||||||
|
/* If link reg is null, we are done. */
|
||||||
|
if (ip == 0x0)
|
||||||
|
break;
|
||||||
|
|
||||||
|
/* If newfp isn't larger, we're tracing garbage. */
|
||||||
|
if (newfp > fp)
|
||||||
|
fp = newfp;
|
||||||
|
else
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
void show_stack(struct task_struct *task, unsigned long *fp)
|
||||||
|
{
|
||||||
|
/* Saved link reg is one word above FP */
|
||||||
|
do_show_stack(task, fp, 0);
|
||||||
|
}
|
||||||
|
|
||||||
|
void dump_stack(void)
|
||||||
|
{
|
||||||
|
unsigned long *fp;
|
||||||
|
asm("%0 = r30" : "=r" (fp));
|
||||||
|
show_stack(current, fp);
|
||||||
|
}
|
||||||
|
EXPORT_SYMBOL(dump_stack);
|
||||||
|
|
||||||
|
int die(const char *str, struct pt_regs *regs, long err)
|
||||||
|
{
|
||||||
|
static struct {
|
||||||
|
spinlock_t lock;
|
||||||
|
int counter;
|
||||||
|
} die = {
|
||||||
|
.lock = __SPIN_LOCK_UNLOCKED(die.lock),
|
||||||
|
.counter = 0
|
||||||
|
};
|
||||||
|
|
||||||
|
console_verbose();
|
||||||
|
oops_enter();
|
||||||
|
|
||||||
|
spin_lock_irq(&die.lock);
|
||||||
|
bust_spinlocks(1);
|
||||||
|
printk(KERN_EMERG "Oops: %s[#%d]:\n", str, ++die.counter);
|
||||||
|
|
||||||
|
if (notify_die(DIE_OOPS, str, regs, err, pt_cause(regs), SIGSEGV) ==
|
||||||
|
NOTIFY_STOP)
|
||||||
|
return 1;
|
||||||
|
|
||||||
|
print_modules();
|
||||||
|
show_regs(regs);
|
||||||
|
do_show_stack(current, ®s->r30, pt_elr(regs));
|
||||||
|
|
||||||
|
bust_spinlocks(0);
|
||||||
|
add_taint(TAINT_DIE);
|
||||||
|
|
||||||
|
spin_unlock_irq(&die.lock);
|
||||||
|
|
||||||
|
if (in_interrupt())
|
||||||
|
panic("Fatal exception in interrupt");
|
||||||
|
|
||||||
|
if (panic_on_oops)
|
||||||
|
panic("Fatal exception");
|
||||||
|
|
||||||
|
oops_exit();
|
||||||
|
do_exit(err);
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
int die_if_kernel(char *str, struct pt_regs *regs, long err)
|
||||||
|
{
|
||||||
|
if (!user_mode(regs))
|
||||||
|
return die(str, regs, err);
|
||||||
|
else
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
/*
|
||||||
|
* It's not clear that misaligned fetches are ever recoverable.
|
||||||
|
*/
|
||||||
|
static void misaligned_instruction(struct pt_regs *regs)
|
||||||
|
{
|
||||||
|
die_if_kernel("Misaligned Instruction", regs, 0);
|
||||||
|
force_sig(SIGBUS, current);
|
||||||
|
}
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Misaligned loads and stores, on the other hand, can be
|
||||||
|
* emulated, and probably should be, some day. But for now
|
||||||
|
* they will be considered fatal.
|
||||||
|
*/
|
||||||
|
static void misaligned_data_load(struct pt_regs *regs)
|
||||||
|
{
|
||||||
|
die_if_kernel("Misaligned Data Load", regs, 0);
|
||||||
|
force_sig(SIGBUS, current);
|
||||||
|
}
|
||||||
|
|
||||||
|
static void misaligned_data_store(struct pt_regs *regs)
|
||||||
|
{
|
||||||
|
die_if_kernel("Misaligned Data Store", regs, 0);
|
||||||
|
force_sig(SIGBUS, current);
|
||||||
|
}
|
||||||
|
|
||||||
|
static void illegal_instruction(struct pt_regs *regs)
|
||||||
|
{
|
||||||
|
die_if_kernel("Illegal Instruction", regs, 0);
|
||||||
|
force_sig(SIGILL, current);
|
||||||
|
}
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Precise bus errors may be recoverable with a a retry,
|
||||||
|
* but for now, treat them as irrecoverable.
|
||||||
|
*/
|
||||||
|
static void precise_bus_error(struct pt_regs *regs)
|
||||||
|
{
|
||||||
|
die_if_kernel("Precise Bus Error", regs, 0);
|
||||||
|
force_sig(SIGBUS, current);
|
||||||
|
}
|
||||||
|
|
||||||
|
/*
|
||||||
|
* If anything is to be done here other than panic,
|
||||||
|
* it will probably be complex and migrate to another
|
||||||
|
* source module. For now, just die.
|
||||||
|
*/
|
||||||
|
static void cache_error(struct pt_regs *regs)
|
||||||
|
{
|
||||||
|
die("Cache Error", regs, 0);
|
||||||
|
}
|
||||||
|
|
||||||
|
/*
|
||||||
|
* General exception handler
|
||||||
|
*/
|
||||||
|
void do_genex(struct pt_regs *regs)
|
||||||
|
{
|
||||||
|
/*
|
||||||
|
* Decode Cause and Dispatch
|
||||||
|
*/
|
||||||
|
switch (pt_cause(regs)) {
|
||||||
|
case HVM_GE_C_XPROT:
|
||||||
|
case HVM_GE_C_XUSER:
|
||||||
|
execute_protection_fault(regs);
|
||||||
|
break;
|
||||||
|
case HVM_GE_C_RPROT:
|
||||||
|
case HVM_GE_C_RUSER:
|
||||||
|
read_protection_fault(regs);
|
||||||
|
break;
|
||||||
|
case HVM_GE_C_WPROT:
|
||||||
|
case HVM_GE_C_WUSER:
|
||||||
|
write_protection_fault(regs);
|
||||||
|
break;
|
||||||
|
case HVM_GE_C_XMAL:
|
||||||
|
misaligned_instruction(regs);
|
||||||
|
break;
|
||||||
|
case HVM_GE_C_RMAL:
|
||||||
|
misaligned_data_load(regs);
|
||||||
|
break;
|
||||||
|
case HVM_GE_C_WMAL:
|
||||||
|
misaligned_data_store(regs);
|
||||||
|
break;
|
||||||
|
case HVM_GE_C_INVI:
|
||||||
|
case HVM_GE_C_PRIVI:
|
||||||
|
illegal_instruction(regs);
|
||||||
|
break;
|
||||||
|
case HVM_GE_C_BUS:
|
||||||
|
precise_bus_error(regs);
|
||||||
|
break;
|
||||||
|
case HVM_GE_C_CACHE:
|
||||||
|
cache_error(regs);
|
||||||
|
break;
|
||||||
|
default:
|
||||||
|
/* Halt and catch fire */
|
||||||
|
panic("Unrecognized exception 0x%lx\n", pt_cause(regs));
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Indirect system call dispatch */
|
||||||
|
long sys_syscall(void)
|
||||||
|
{
|
||||||
|
printk(KERN_ERR "sys_syscall invoked!\n");
|
||||||
|
return -ENOSYS;
|
||||||
|
}
|
||||||
|
|
||||||
|
void do_trap0(struct pt_regs *regs)
|
||||||
|
{
|
||||||
|
unsigned long syscallret = 0;
|
||||||
|
syscall_fn syscall;
|
||||||
|
|
||||||
|
switch (pt_cause(regs)) {
|
||||||
|
case TRAP_SYSCALL:
|
||||||
|
/* System call is trap0 #1 */
|
||||||
|
|
||||||
|
/* allow strace to catch syscall args */
|
||||||
|
if (unlikely(test_thread_flag(TIF_SYSCALL_TRACE) &&
|
||||||
|
tracehook_report_syscall_entry(regs)))
|
||||||
|
return; /* return -ENOSYS somewhere? */
|
||||||
|
|
||||||
|
/* Interrupts should be re-enabled for syscall processing */
|
||||||
|
__vmsetie(VM_INT_ENABLE);
|
||||||
|
|
||||||
|
/*
|
||||||
|
* System call number is in r6, arguments in r0..r5.
|
||||||
|
* Fortunately, no Linux syscall has more than 6 arguments,
|
||||||
|
* and Hexagon ABI passes first 6 arguments in registers.
|
||||||
|
* 64-bit arguments are passed in odd/even register pairs.
|
||||||
|
* Fortunately, we have no system calls that take more
|
||||||
|
* than three arguments with more than one 64-bit value.
|
||||||
|
* Should that change, we'd need to redesign to copy
|
||||||
|
* between user and kernel stacks.
|
||||||
|
*/
|
||||||
|
regs->syscall_nr = regs->r06;
|
||||||
|
|
||||||
|
/*
|
||||||
|
* GPR R0 carries the first parameter, and is also used
|
||||||
|
* to report the return value. We need a backup of
|
||||||
|
* the user's value in case we need to do a late restart
|
||||||
|
* of the system call.
|
||||||
|
*/
|
||||||
|
regs->restart_r0 = regs->r00;
|
||||||
|
|
||||||
|
if ((unsigned long) regs->syscall_nr >= __NR_syscalls) {
|
||||||
|
regs->r00 = -1;
|
||||||
|
} else {
|
||||||
|
syscall = (syscall_fn)
|
||||||
|
(sys_call_table[regs->syscall_nr]);
|
||||||
|
syscallret = syscall(regs->r00, regs->r01,
|
||||||
|
regs->r02, regs->r03,
|
||||||
|
regs->r04, regs->r05);
|
||||||
|
}
|
||||||
|
|
||||||
|
/*
|
||||||
|
* If it was a sigreturn system call, don't overwrite
|
||||||
|
* r0 value in stack frame with return value.
|
||||||
|
*
|
||||||
|
* __NR_sigreturn doesn't seem to exist in new unistd.h
|
||||||
|
*/
|
||||||
|
|
||||||
|
if (regs->syscall_nr != __NR_rt_sigreturn)
|
||||||
|
regs->r00 = syscallret;
|
||||||
|
|
||||||
|
/* allow strace to get the syscall return state */
|
||||||
|
if (unlikely(test_thread_flag(TIF_SYSCALL_TRACE)))
|
||||||
|
tracehook_report_syscall_exit(regs, 0);
|
||||||
|
|
||||||
|
break;
|
||||||
|
case TRAP_DEBUG:
|
||||||
|
/* Trap0 0xdb is debug breakpoint */
|
||||||
|
if (user_mode(regs)) {
|
||||||
|
struct siginfo info;
|
||||||
|
|
||||||
|
info.si_signo = SIGTRAP;
|
||||||
|
info.si_errno = 0;
|
||||||
|
/*
|
||||||
|
* Some architecures add some per-thread state
|
||||||
|
* to distinguish between breakpoint traps and
|
||||||
|
* trace traps. We may want to do that, and
|
||||||
|
* set the si_code value appropriately, or we
|
||||||
|
* may want to use a different trap0 flavor.
|
||||||
|
*/
|
||||||
|
info.si_code = TRAP_BRKPT;
|
||||||
|
info.si_addr = (void __user *) pt_elr(regs);
|
||||||
|
send_sig_info(SIGTRAP, &info, current);
|
||||||
|
} else {
|
||||||
|
#ifdef CONFIG_KGDB
|
||||||
|
kgdb_handle_exception(pt_cause(regs), SIGTRAP,
|
||||||
|
TRAP_BRKPT, regs);
|
||||||
|
#endif
|
||||||
|
}
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
/* Ignore other trap0 codes for now, especially 0 (Angel calls) */
|
||||||
|
}
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Machine check exception handler
|
||||||
|
*/
|
||||||
|
void do_machcheck(struct pt_regs *regs)
|
||||||
|
{
|
||||||
|
/* Halt and catch fire */
|
||||||
|
__vmstop();
|
||||||
|
}
|
||||||
Loading…
Add table
Add a link
Reference in a new issue