diff options
| -rw-r--r-- | arch/sh/kernel/entry-common.S | 2 | ||||
| -rw-r--r-- | arch/sh/kernel/ptrace.c | 45 | ||||
| -rw-r--r-- | include/asm-sh/thread_info.h | 2 |
3 files changed, 36 insertions, 13 deletions
diff --git a/arch/sh/kernel/entry-common.S b/arch/sh/kernel/entry-common.S index ab4ebb856c2..b4672802719 100644 --- a/arch/sh/kernel/entry-common.S +++ b/arch/sh/kernel/entry-common.S @@ -224,7 +224,7 @@ work_resched: syscall_exit_work: ! r0: current_thread_info->flags ! r8: current_thread_info - tst #_TIF_SYSCALL_TRACE, r0 + tst #_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP, r0 bt/s work_pending tst #_TIF_NEED_RESCHED, r0 #ifdef CONFIG_TRACE_IRQFLAGS diff --git a/arch/sh/kernel/ptrace.c b/arch/sh/kernel/ptrace.c index 04ca13a041c..855f7246cff 100644 --- a/arch/sh/kernel/ptrace.c +++ b/arch/sh/kernel/ptrace.c @@ -8,7 +8,6 @@ * SuperH version: Copyright (C) 1999, 2000 Kaz Kojima & Niibe Yutaka * */ - #include <linux/kernel.h> #include <linux/sched.h> #include <linux/mm.h> @@ -20,8 +19,7 @@ #include <linux/slab.h> #include <linux/security.h> #include <linux/signal.h> - -#include <asm/io.h> +#include <linux/io.h> #include <asm/uaccess.h> #include <asm/pgtable.h> #include <asm/system.h> @@ -59,6 +57,23 @@ static inline int put_stack_long(struct task_struct *task, int offset, return 0; } +static void ptrace_disable_singlestep(struct task_struct *child) +{ + clear_tsk_thread_flag(child, TIF_SINGLESTEP); + + /* + * Ensure the UBC is not programmed at the next context switch. + * + * Normally this is not needed but there are sequences such as + * singlestep, signal delivery, and continue that leave the + * ubc_pc non-zero leading to spurious SIGTRAPs. + */ + if (child->thread.ubc_pc != 0) { + ubc_usercnt -= 1; + child->thread.ubc_pc = 0; + } +} + /* * Called by kernel/ptrace.c when detaching.. * @@ -66,7 +81,7 @@ static inline int put_stack_long(struct task_struct *task, int offset, */ void ptrace_disable(struct task_struct *child) { - /* nothing to do.. */ + ptrace_disable_singlestep(child); } long arch_ptrace(struct task_struct *child, long request, long addr, long data) @@ -76,7 +91,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) switch (request) { /* when I and D space are separate, these will need to be fixed. */ - case PTRACE_PEEKTEXT: /* read word at location addr. */ + case PTRACE_PEEKTEXT: /* read word at location addr. */ case PTRACE_PEEKDATA: { unsigned long tmp; int copied; @@ -94,7 +109,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) unsigned long tmp; ret = -EIO; - if ((addr & 3) || addr < 0 || + if ((addr & 3) || addr < 0 || addr > sizeof(struct user) - 3) break; @@ -129,7 +144,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) case PTRACE_POKEUSR: /* write the word at location addr in the USER area */ ret = -EIO; - if ((addr & 3) || addr < 0 || + if ((addr & 3) || addr < 0 || addr > sizeof(struct user) - 3) break; @@ -156,6 +171,9 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); else clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); + + ptrace_disable_singlestep(child); + child->exit_code = data; wake_up_process(child); ret = 0; @@ -163,14 +181,15 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) } /* - * make the child exit. Best I can do is send it a sigkill. - * perhaps it should be put in the status that it wants to + * make the child exit. Best I can do is send it a sigkill. + * perhaps it should be put in the status that it wants to * exit. */ case PTRACE_KILL: { ret = 0; if (child->exit_state == EXIT_ZOMBIE) /* already dead */ break; + ptrace_disable_singlestep(child); child->exit_code = SIGKILL; wake_up_process(child); break; @@ -196,6 +215,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) ubc_usercnt += 1; child->thread.ubc_pc = pc; + set_tsk_thread_flag(child, TIF_SINGLESTEP); child->exit_code = data; /* give it a chance to run. */ wake_up_process(child); @@ -248,14 +268,15 @@ asmlinkage void do_syscall_trace(void) { struct task_struct *tsk = current; - if (!test_thread_flag(TIF_SYSCALL_TRACE)) + if (!test_thread_flag(TIF_SYSCALL_TRACE) && + !test_thread_flag(TIF_SINGLESTEP)) return; if (!(tsk->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)); + ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) && + !test_thread_flag(TIF_SINGLESTEP) ? 0x80 : 0)); /* * this isn't the same as continuing with a signal, but it will do diff --git a/include/asm-sh/thread_info.h b/include/asm-sh/thread_info.h index 279e70a77c7..31d55e3782d 100644 --- a/include/asm-sh/thread_info.h +++ b/include/asm-sh/thread_info.h @@ -111,6 +111,7 @@ static inline struct thread_info *current_thread_info(void) #define TIF_SIGPENDING 2 /* signal pending */ #define TIF_NEED_RESCHED 3 /* rescheduling necessary */ #define TIF_RESTORE_SIGMASK 4 /* restore signal mask in do_signal() */ +#define TIF_SINGLESTEP 5 /* singlestepping active */ #define TIF_USEDFPU 16 /* FPU was used by this task this quantum (SMP) */ #define TIF_POLLING_NRFLAG 17 /* true if poll_idle() is polling TIF_NEED_RESCHED */ #define TIF_MEMDIE 18 @@ -121,6 +122,7 @@ static inline struct thread_info *current_thread_info(void) #define _TIF_SIGPENDING (1<<TIF_SIGPENDING) #define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED) #define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK) +#define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP) #define _TIF_USEDFPU (1<<TIF_USEDFPU) #define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG) #define _TIF_FREEZE (1<<TIF_FREEZE) |