mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-05 23:16:42 +07:00
9f29b8fb41
use new 'datap' variable type of void pointer in order to remove unnecessary castings. Signed-off-by: Namhyung Kim <namhyung@gmail.com> Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
357 lines
9.2 KiB
C
357 lines
9.2 KiB
C
/*
|
|
* Copyright (C) 2004-2006 Atmel Corporation
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
#undef DEBUG
|
|
#include <linux/kernel.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/ptrace.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/user.h>
|
|
#include <linux/security.h>
|
|
#include <linux/unistd.h>
|
|
#include <linux/notifier.h>
|
|
|
|
#include <asm/traps.h>
|
|
#include <asm/uaccess.h>
|
|
#include <asm/ocd.h>
|
|
#include <asm/mmu_context.h>
|
|
#include <linux/kdebug.h>
|
|
|
|
static struct pt_regs *get_user_regs(struct task_struct *tsk)
|
|
{
|
|
return (struct pt_regs *)((unsigned long)task_stack_page(tsk) +
|
|
THREAD_SIZE - sizeof(struct pt_regs));
|
|
}
|
|
|
|
void user_enable_single_step(struct task_struct *tsk)
|
|
{
|
|
pr_debug("user_enable_single_step: pid=%u, PC=0x%08lx, SR=0x%08lx\n",
|
|
tsk->pid, task_pt_regs(tsk)->pc, task_pt_regs(tsk)->sr);
|
|
|
|
/*
|
|
* We can't schedule in Debug mode, so when TIF_BREAKPOINT is
|
|
* set, the system call or exception handler will do a
|
|
* breakpoint to enter monitor mode before returning to
|
|
* userspace.
|
|
*
|
|
* The monitor code will then notice that TIF_SINGLE_STEP is
|
|
* set and return to userspace with single stepping enabled.
|
|
* The CPU will then enter monitor mode again after exactly
|
|
* one instruction has been executed, and the monitor code
|
|
* will then send a SIGTRAP to the process.
|
|
*/
|
|
set_tsk_thread_flag(tsk, TIF_BREAKPOINT);
|
|
set_tsk_thread_flag(tsk, TIF_SINGLE_STEP);
|
|
}
|
|
|
|
void user_disable_single_step(struct task_struct *child)
|
|
{
|
|
/* XXX(hch): a no-op here seems wrong.. */
|
|
}
|
|
|
|
/*
|
|
* Called by kernel/ptrace.c when detaching
|
|
*
|
|
* Make sure any single step bits, etc. are not set
|
|
*/
|
|
void ptrace_disable(struct task_struct *child)
|
|
{
|
|
clear_tsk_thread_flag(child, TIF_SINGLE_STEP);
|
|
clear_tsk_thread_flag(child, TIF_BREAKPOINT);
|
|
ocd_disable(child);
|
|
}
|
|
|
|
/*
|
|
* Read the word at offset "offset" into the task's "struct user". We
|
|
* actually access the pt_regs struct stored on the kernel stack.
|
|
*/
|
|
static int ptrace_read_user(struct task_struct *tsk, unsigned long offset,
|
|
unsigned long __user *data)
|
|
{
|
|
unsigned long *regs;
|
|
unsigned long value;
|
|
|
|
if (offset & 3 || offset >= sizeof(struct user)) {
|
|
printk("ptrace_read_user: invalid offset 0x%08lx\n", offset);
|
|
return -EIO;
|
|
}
|
|
|
|
regs = (unsigned long *)get_user_regs(tsk);
|
|
|
|
value = 0;
|
|
if (offset < sizeof(struct pt_regs))
|
|
value = regs[offset / sizeof(regs[0])];
|
|
|
|
pr_debug("ptrace_read_user(%s[%u], %#lx, %p) -> %#lx\n",
|
|
tsk->comm, tsk->pid, offset, data, value);
|
|
|
|
return put_user(value, data);
|
|
}
|
|
|
|
/*
|
|
* Write the word "value" to offset "offset" into the task's "struct
|
|
* user". We actually access the pt_regs struct stored on the kernel
|
|
* stack.
|
|
*/
|
|
static int ptrace_write_user(struct task_struct *tsk, unsigned long offset,
|
|
unsigned long value)
|
|
{
|
|
unsigned long *regs;
|
|
|
|
pr_debug("ptrace_write_user(%s[%u], %#lx, %#lx)\n",
|
|
tsk->comm, tsk->pid, offset, value);
|
|
|
|
if (offset & 3 || offset >= sizeof(struct user)) {
|
|
pr_debug(" invalid offset 0x%08lx\n", offset);
|
|
return -EIO;
|
|
}
|
|
|
|
if (offset >= sizeof(struct pt_regs))
|
|
return 0;
|
|
|
|
regs = (unsigned long *)get_user_regs(tsk);
|
|
regs[offset / sizeof(regs[0])] = value;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ptrace_getregs(struct task_struct *tsk, void __user *uregs)
|
|
{
|
|
struct pt_regs *regs = get_user_regs(tsk);
|
|
|
|
return copy_to_user(uregs, regs, sizeof(*regs)) ? -EFAULT : 0;
|
|
}
|
|
|
|
static int ptrace_setregs(struct task_struct *tsk, const void __user *uregs)
|
|
{
|
|
struct pt_regs newregs;
|
|
int ret;
|
|
|
|
ret = -EFAULT;
|
|
if (copy_from_user(&newregs, uregs, sizeof(newregs)) == 0) {
|
|
struct pt_regs *regs = get_user_regs(tsk);
|
|
|
|
ret = -EINVAL;
|
|
if (valid_user_regs(&newregs)) {
|
|
*regs = newregs;
|
|
ret = 0;
|
|
}
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
long arch_ptrace(struct task_struct *child, long request,
|
|
unsigned long addr, unsigned long data)
|
|
{
|
|
int ret;
|
|
void __user *datap = (void __user *) data;
|
|
|
|
switch (request) {
|
|
/* Read the word at location addr in the child process */
|
|
case PTRACE_PEEKTEXT:
|
|
case PTRACE_PEEKDATA:
|
|
ret = generic_ptrace_peekdata(child, addr, data);
|
|
break;
|
|
|
|
case PTRACE_PEEKUSR:
|
|
ret = ptrace_read_user(child, addr, datap);
|
|
break;
|
|
|
|
/* Write the word in data at location addr */
|
|
case PTRACE_POKETEXT:
|
|
case PTRACE_POKEDATA:
|
|
ret = generic_ptrace_pokedata(child, addr, data);
|
|
break;
|
|
|
|
case PTRACE_POKEUSR:
|
|
ret = ptrace_write_user(child, addr, data);
|
|
break;
|
|
|
|
case PTRACE_GETREGS:
|
|
ret = ptrace_getregs(child, datap);
|
|
break;
|
|
|
|
case PTRACE_SETREGS:
|
|
ret = ptrace_setregs(child, datap);
|
|
break;
|
|
|
|
default:
|
|
ret = ptrace_request(child, request, addr, data);
|
|
break;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
asmlinkage void syscall_trace(void)
|
|
{
|
|
if (!test_thread_flag(TIF_SYSCALL_TRACE))
|
|
return;
|
|
if (!(current->ptrace & PT_PTRACED))
|
|
return;
|
|
|
|
/* The 0x80 provides a way for the tracing parent to
|
|
* distinguish between a syscall stop and SIGTRAP delivery */
|
|
ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
|
|
? 0x80 : 0));
|
|
|
|
/*
|
|
* this isn't the same as continuing with a signal, but it
|
|
* will do for normal use. strace only continues with a
|
|
* signal if the stopping signal is not SIGTRAP. -brl
|
|
*/
|
|
if (current->exit_code) {
|
|
pr_debug("syscall_trace: sending signal %d to PID %u\n",
|
|
current->exit_code, current->pid);
|
|
send_sig(current->exit_code, current, 1);
|
|
current->exit_code = 0;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* debug_trampoline() is an assembly stub which will store all user
|
|
* registers on the stack and execute a breakpoint instruction.
|
|
*
|
|
* If we single-step into an exception handler which runs with
|
|
* interrupts disabled the whole time so it doesn't have to check for
|
|
* pending work, its return address will be modified so that it ends
|
|
* up returning to debug_trampoline.
|
|
*
|
|
* If the exception handler decides to store the user context and
|
|
* enable interrupts after all, it will restore the original return
|
|
* address and status register value. Before it returns, it will
|
|
* notice that TIF_BREAKPOINT is set and execute a breakpoint
|
|
* instruction.
|
|
*/
|
|
extern void debug_trampoline(void);
|
|
|
|
asmlinkage struct pt_regs *do_debug(struct pt_regs *regs)
|
|
{
|
|
struct thread_info *ti;
|
|
unsigned long trampoline_addr;
|
|
u32 status;
|
|
u32 ctrl;
|
|
int code;
|
|
|
|
status = ocd_read(DS);
|
|
ti = current_thread_info();
|
|
code = TRAP_BRKPT;
|
|
|
|
pr_debug("do_debug: status=0x%08x PC=0x%08lx SR=0x%08lx tif=0x%08lx\n",
|
|
status, regs->pc, regs->sr, ti->flags);
|
|
|
|
if (!user_mode(regs)) {
|
|
unsigned long die_val = DIE_BREAKPOINT;
|
|
|
|
if (status & (1 << OCD_DS_SSS_BIT))
|
|
die_val = DIE_SSTEP;
|
|
|
|
if (notify_die(die_val, "ptrace", regs, 0, 0, SIGTRAP)
|
|
== NOTIFY_STOP)
|
|
return regs;
|
|
|
|
if ((status & (1 << OCD_DS_SWB_BIT))
|
|
&& test_and_clear_ti_thread_flag(
|
|
ti, TIF_BREAKPOINT)) {
|
|
/*
|
|
* Explicit breakpoint from trampoline or
|
|
* exception/syscall/interrupt handler.
|
|
*
|
|
* The real saved regs are on the stack right
|
|
* after the ones we saved on entry.
|
|
*/
|
|
regs++;
|
|
pr_debug(" -> TIF_BREAKPOINT done, adjusted regs:"
|
|
"PC=0x%08lx SR=0x%08lx\n",
|
|
regs->pc, regs->sr);
|
|
BUG_ON(!user_mode(regs));
|
|
|
|
if (test_thread_flag(TIF_SINGLE_STEP)) {
|
|
pr_debug("Going to do single step...\n");
|
|
return regs;
|
|
}
|
|
|
|
/*
|
|
* No TIF_SINGLE_STEP means we're done
|
|
* stepping over a syscall. Do the trap now.
|
|
*/
|
|
code = TRAP_TRACE;
|
|
} else if ((status & (1 << OCD_DS_SSS_BIT))
|
|
&& test_ti_thread_flag(ti, TIF_SINGLE_STEP)) {
|
|
|
|
pr_debug("Stepped into something, "
|
|
"setting TIF_BREAKPOINT...\n");
|
|
set_ti_thread_flag(ti, TIF_BREAKPOINT);
|
|
|
|
/*
|
|
* We stepped into an exception, interrupt or
|
|
* syscall handler. Some exception handlers
|
|
* don't check for pending work, so we need to
|
|
* set up a trampoline just in case.
|
|
*
|
|
* The exception entry code will undo the
|
|
* trampoline stuff if it does a full context
|
|
* save (which also means that it'll check for
|
|
* pending work later.)
|
|
*/
|
|
if ((regs->sr & MODE_MASK) == MODE_EXCEPTION) {
|
|
trampoline_addr
|
|
= (unsigned long)&debug_trampoline;
|
|
|
|
pr_debug("Setting up trampoline...\n");
|
|
ti->rar_saved = sysreg_read(RAR_EX);
|
|
ti->rsr_saved = sysreg_read(RSR_EX);
|
|
sysreg_write(RAR_EX, trampoline_addr);
|
|
sysreg_write(RSR_EX, (MODE_EXCEPTION
|
|
| SR_EM | SR_GM));
|
|
BUG_ON(ti->rsr_saved & MODE_MASK);
|
|
}
|
|
|
|
/*
|
|
* If we stepped into a system call, we
|
|
* shouldn't do a single step after we return
|
|
* since the return address is right after the
|
|
* "scall" instruction we were told to step
|
|
* over.
|
|
*/
|
|
if ((regs->sr & MODE_MASK) == MODE_SUPERVISOR) {
|
|
pr_debug("Supervisor; no single step\n");
|
|
clear_ti_thread_flag(ti, TIF_SINGLE_STEP);
|
|
}
|
|
|
|
ctrl = ocd_read(DC);
|
|
ctrl &= ~(1 << OCD_DC_SS_BIT);
|
|
ocd_write(DC, ctrl);
|
|
|
|
return regs;
|
|
} else {
|
|
printk(KERN_ERR "Unexpected OCD_DS value: 0x%08x\n",
|
|
status);
|
|
printk(KERN_ERR "Thread flags: 0x%08lx\n", ti->flags);
|
|
die("Unhandled debug trap in kernel mode",
|
|
regs, SIGTRAP);
|
|
}
|
|
} else if (status & (1 << OCD_DS_SSS_BIT)) {
|
|
/* Single step in user mode */
|
|
code = TRAP_TRACE;
|
|
|
|
ctrl = ocd_read(DC);
|
|
ctrl &= ~(1 << OCD_DC_SS_BIT);
|
|
ocd_write(DC, ctrl);
|
|
}
|
|
|
|
pr_debug("Sending SIGTRAP: code=%d PC=0x%08lx SR=0x%08lx\n",
|
|
code, regs->pc, regs->sr);
|
|
|
|
clear_thread_flag(TIF_SINGLE_STEP);
|
|
_exception(SIGTRAP, regs, code, instruction_pointer(regs));
|
|
|
|
return regs;
|
|
}
|