diff options
| -rw-r--r-- | arch/mips/kernel/process.c | 36 | ||||
| -rw-r--r-- | arch/mips/kernel/stacktrace.c | 32 | ||||
| -rw-r--r-- | arch/mips/kernel/traps.c | 3 | ||||
| -rw-r--r-- | include/asm-mips/stacktrace.h | 2 |
4 files changed, 39 insertions, 34 deletions
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c index 6955380..045d987 100644 --- a/arch/mips/kernel/process.c +++ b/arch/mips/kernel/process.c @@ -399,7 +399,7 @@ unsigned long thread_saved_pc(struct task_struct *tsk) #ifdef CONFIG_KALLSYMS /* used by show_backtrace() */ unsigned long unwind_stack(struct task_struct *task, unsigned long *sp, - unsigned long pc, unsigned long ra) + unsigned long pc, unsigned long *ra) { unsigned long stack_page; struct mips_frame_info info; @@ -407,18 +407,42 @@ unsigned long unwind_stack(struct task_struct *task, unsigned long *sp, char namebuf[KSYM_NAME_LEN + 1]; unsigned long size, ofs; int leaf; + extern void ret_from_irq(void); + extern void ret_from_exception(void); stack_page = (unsigned long)task_stack_page(task); if (!stack_page) return 0; + /* + * If we reached the bottom of interrupt context, + * return saved pc in pt_regs. + */ + if (pc == (unsigned long)ret_from_irq || + pc == (unsigned long)ret_from_exception) { + struct pt_regs *regs; + if (*sp >= stack_page && + *sp + sizeof(*regs) <= stack_page + THREAD_SIZE - 32) { + regs = (struct pt_regs *)*sp; + pc = regs->cp0_epc; + if (__kernel_text_address(pc)) { + *sp = regs->regs[29]; + *ra = regs->regs[31]; + return pc; + } + } + return 0; + } if (!kallsyms_lookup(pc, &size, &ofs, &modname, namebuf)) return 0; /* * Return ra if an exception occured at the first instruction */ - if (unlikely(ofs == 0)) - return ra; + if (unlikely(ofs == 0)) { + pc = *ra; + *ra = 0; + return pc; + } info.func = (void *)(pc - ofs); info.func_size = ofs; /* analyze from start to ofs */ @@ -437,11 +461,12 @@ unsigned long unwind_stack(struct task_struct *task, unsigned long *sp, * one. In that cases avoid to return always the * same value. */ - pc = pc != ra ? ra : 0; + pc = pc != *ra ? *ra : 0; else pc = ((unsigned long *)(*sp))[info.pc_offset]; *sp += info.frame_size; + *ra = 0; return __kernel_text_address(pc) ? pc : 0; } #endif @@ -454,6 +479,7 @@ unsigned long get_wchan(struct task_struct *task) unsigned long pc = 0; #ifdef CONFIG_KALLSYMS unsigned long sp; + unsigned long ra = 0; #endif if (!task || task == current || task->state == TASK_RUNNING) @@ -467,7 +493,7 @@ unsigned long get_wchan(struct task_struct *task) sp = task->thread.reg29 + schedule_mfi.frame_size; while (in_sched_functions(pc)) - pc = unwind_stack(task, &sp, pc, 0); + pc = unwind_stack(task, &sp, pc, &ra); #endif out: diff --git a/arch/mips/kernel/stacktrace.c b/arch/mips/kernel/stacktrace.c index 676e6f6..4aabe52 100644 --- a/arch/mips/kernel/stacktrace.c +++ b/arch/mips/kernel/stacktrace.c @@ -31,23 +31,21 @@ static void save_raw_context_stack(struct stack_trace *trace, } } -static struct pt_regs * save_context_stack(struct stack_trace *trace, +static void save_context_stack(struct stack_trace *trace, struct task_struct *task, struct pt_regs *regs) { unsigned long sp = regs->regs[29]; #ifdef CONFIG_KALLSYMS unsigned long ra = regs->regs[31]; unsigned long pc = regs->cp0_epc; - unsigned long stack_page = - (unsigned long)task_stack_page(task); - extern void ret_from_irq(void); - extern void ret_from_exception(void); if (raw_show_trace || !__kernel_text_address(pc)) { + unsigned long stack_page = + (unsigned long)task_stack_page(task); if (stack_page && sp >= stack_page && sp <= stack_page + THREAD_SIZE - 32) save_raw_context_stack(trace, sp); - return NULL; + return; } do { if (trace->skip > 0) @@ -56,25 +54,11 @@ static struct pt_regs * save_context_stack(struct stack_trace *trace, trace->entries[trace->nr_entries++] = pc; if (trace->nr_entries >= trace->max_entries) break; - /* - * If we reached the bottom of interrupt context, - * return saved pt_regs. - */ - if (pc == (unsigned long)ret_from_irq || - pc == (unsigned long)ret_from_exception) { - if (stack_page && sp >= stack_page && - sp <= stack_page + THREAD_SIZE - 32) - return (struct pt_regs *)sp; - break; - } - pc = unwind_stack(task, &sp, pc, ra); - ra = 0; + pc = unwind_stack(task, &sp, pc, &ra); } while (pc); #else save_raw_context_stack(sp); #endif - - return NULL; } /* @@ -97,9 +81,5 @@ void save_stack_trace(struct stack_trace *trace, struct task_struct *task) prepare_frametrace(regs); } - while (1) { - regs = save_context_stack(trace, task, regs); - if (!regs || trace->nr_entries >= trace->max_entries) - break; - } + save_context_stack(trace, task, regs); } diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c index 440b865..b7292a5 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -115,8 +115,7 @@ static void show_backtrace(struct task_struct *task, struct pt_regs *regs) printk("Call Trace:\n"); do { print_ip_sym(pc); - pc = unwind_stack(task, &sp, pc, ra); - ra = 0; + pc = unwind_stack(task, &sp, pc, &ra); } while (pc); printk("\n"); } diff --git a/include/asm-mips/stacktrace.h b/include/asm-mips/stacktrace.h index 231f6f8..07f8733 100644 --- a/include/asm-mips/stacktrace.h +++ b/include/asm-mips/stacktrace.h @@ -6,7 +6,7 @@ #ifdef CONFIG_KALLSYMS extern int raw_show_trace; extern unsigned long unwind_stack(struct task_struct *task, unsigned long *sp, - unsigned long pc, unsigned long ra); + unsigned long pc, unsigned long *ra); #else #define raw_show_trace 1 #define unwind_stack(task, sp, pc, ra) 0 |