diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/sh/include/asm/ptrace.h | 6 | ||||
| -rw-r--r-- | arch/sh/kernel/hw_breakpoint.c | 15 | ||||
| -rw-r--r-- | arch/sh/kernel/ptrace_32.c | 53 |
3 files changed, 71 insertions, 3 deletions
diff --git a/arch/sh/include/asm/ptrace.h b/arch/sh/include/asm/ptrace.h index 1dc12cb44a2..201d11ef211 100644 --- a/arch/sh/include/asm/ptrace.h +++ b/arch/sh/include/asm/ptrace.h @@ -124,6 +124,12 @@ struct task_struct; extern void user_enable_single_step(struct task_struct *); extern void user_disable_single_step(struct task_struct *); +struct perf_event; +struct perf_sample_data; + +extern void ptrace_triggered(struct perf_event *bp, int nmi, + struct perf_sample_data *data, struct pt_regs *regs); + #define task_pt_regs(task) \ ((struct pt_regs *) (task_stack_page(task) + THREAD_SIZE) - 1) diff --git a/arch/sh/kernel/hw_breakpoint.c b/arch/sh/kernel/hw_breakpoint.c index 022d8ed66bd..c515a3ecf56 100644 --- a/arch/sh/kernel/hw_breakpoint.c +++ b/arch/sh/kernel/hw_breakpoint.c @@ -20,6 +20,7 @@ #include <linux/io.h> #include <asm/hw_breakpoint.h> #include <asm/mmu_context.h> +#include <asm/ptrace.h> struct ubc_context { unsigned long pc; @@ -372,7 +373,7 @@ static int __kprobes hw_breakpoint_handler(struct die_args *args) rcu_read_unlock(); } - if (bp) { + if (bp && bp->overflow_handler != ptrace_triggered) { struct arch_hw_breakpoint *info = counter_arch_bp(bp); __raw_writel(UBC_CBR_CE | info->len | info->type, UBC_CBR0); @@ -387,9 +388,19 @@ static int __kprobes hw_breakpoint_handler(struct die_args *args) BUILD_TRAP_HANDLER(breakpoint) { unsigned long ex = lookup_exception_vector(); + siginfo_t info; + int err; TRAP_HANDLER_DECL; - notify_die(DIE_BREAKPOINT, "breakpoint", regs, 0, ex, SIGTRAP); + err = notify_die(DIE_BREAKPOINT, "breakpoint", regs, 0, ex, SIGTRAP); + if (err == NOTIFY_STOP) + return; + + /* Deliver the signal to userspace */ + info.si_signo = SIGTRAP; + info.si_errno = 0; + info.si_code = TRAP_HWBKPT; + force_sig_info(SIGTRAP, &info, current); } /* diff --git a/arch/sh/kernel/ptrace_32.c b/arch/sh/kernel/ptrace_32.c index bdb10446cba..8e094c4c7bb 100644 --- a/arch/sh/kernel/ptrace_32.c +++ b/arch/sh/kernel/ptrace_32.c @@ -2,7 +2,7 @@ * SuperH process tracing * * Copyright (C) 1999, 2000 Kaz Kojima & Niibe Yutaka - * Copyright (C) 2002 - 2008 Paul Mundt + * Copyright (C) 2002 - 2009 Paul Mundt * * Audit support by Yuichi Nakamura <ynakam@hitachisoft.jp> * @@ -26,6 +26,7 @@ #include <linux/tracehook.h> #include <linux/elf.h> #include <linux/regset.h> +#include <linux/hw_breakpoint.h> #include <asm/uaccess.h> #include <asm/pgtable.h> #include <asm/system.h> @@ -63,9 +64,59 @@ static inline int put_stack_long(struct task_struct *task, int offset, return 0; } +void ptrace_triggered(struct perf_event *bp, int nmi, + struct perf_sample_data *data, struct pt_regs *regs) +{ + struct perf_event_attr attr; + + /* + * Disable the breakpoint request here since ptrace has defined a + * one-shot behaviour for breakpoint exceptions. + */ + attr = bp->attr; + attr.disabled = true; + modify_user_hw_breakpoint(bp, &attr); +} + +static int set_single_step(struct task_struct *tsk, unsigned long addr) +{ + struct thread_struct *thread = &tsk->thread; + struct perf_event *bp; + struct perf_event_attr attr; + + bp = thread->ptrace_bps[0]; + if (!bp) { + hw_breakpoint_init(&attr); + + attr.bp_addr = addr; + attr.bp_len = HW_BREAKPOINT_LEN_2; + attr.bp_type = HW_BREAKPOINT_R; + + bp = register_user_hw_breakpoint(&attr, ptrace_triggered, tsk); + if (IS_ERR(bp)) + return PTR_ERR(bp); + + thread->ptrace_bps[0] = bp; + } else { + int err; + + attr = bp->attr; + attr.bp_addr = addr; + err = modify_user_hw_breakpoint(bp, &attr); + if (unlikely(err)) + return err; + } + + return 0; +} + void user_enable_single_step(struct task_struct *child) { + unsigned long pc = get_stack_long(child, offsetof(struct pt_regs, pc)); + set_tsk_thread_flag(child, TIF_SINGLESTEP); + + set_single_step(child, pc); } void user_disable_single_step(struct task_struct *child) |