diff options
| author | Keith Packard <keithp@keithp.com> | 2016-03-26 15:54:24 -0700 |
|---|---|---|
| committer | Keith Packard <keithp@keithp.com> | 2016-03-26 16:07:20 -0700 |
| commit | 4fa71ecf168e275b24534a5a20e3dd4e178c7bbd (patch) | |
| tree | d3d042dbb8a3dff4d3133959db64dd6d90055c0d /src | |
| parent | 6a9546413d6a236c010e806b50506d870961d074 (diff) | |
altos/stm: Validate current task SP in interrupt by looking at PSP
We use a separate stack pointer for task code, which means we can
verify that it is in range in any interrupt handler. This adds checks
for the task stack (under #ifdef DEBUG) that run in ao_wakeup as well
as at every timer interrupt.
Signed-off-by: Keith Packard <keithp@keithp.com>
Diffstat (limited to 'src')
| -rw-r--r-- | src/kernel/ao_task.c | 2 | ||||
| -rw-r--r-- | src/kernel/ao_task.h | 4 | ||||
| -rw-r--r-- | src/stm/ao_arch_funcs.h | 16 | ||||
| -rw-r--r-- | src/stm/ao_timer.c | 1 |
4 files changed, 22 insertions, 1 deletions
diff --git a/src/kernel/ao_task.c b/src/kernel/ao_task.c index 55e423bb..104d1074 100644 --- a/src/kernel/ao_task.c +++ b/src/kernel/ao_task.c @@ -355,7 +355,6 @@ ao_yield(void) ao_arch_naked_define */ if (ao_cur_task->wchan == NULL) ao_task_to_run_queue(ao_cur_task); - ao_cur_task = NULL; for (;;) { ao_arch_memory_barrier(); if (!ao_list_is_empty(&run_queue)) @@ -425,6 +424,7 @@ ao_sleep(__xdata void *wchan) void ao_wakeup(__xdata void *wchan) __reentrant { + ao_validate_cur_stack(); #if HAS_TASK_QUEUE struct ao_task *sleep, *next; struct ao_list *sleep_queue; diff --git a/src/kernel/ao_task.h b/src/kernel/ao_task.h index c6bec0e3..0e353fe8 100644 --- a/src/kernel/ao_task.h +++ b/src/kernel/ao_task.h @@ -56,6 +56,10 @@ extern __data uint8_t ao_num_tasks; extern __xdata struct ao_task *__data ao_cur_task; extern __data uint8_t ao_task_minimize_latency; /* Reduce IRQ latency */ +#ifndef HAS_ARCH_VALIDATE_CUR_STACK +#define ao_validate_cur_stack() +#endif + /* ao_task.c */ diff --git a/src/stm/ao_arch_funcs.h b/src/stm/ao_arch_funcs.h index 02b344b1..6b38032c 100644 --- a/src/stm/ao_arch_funcs.h +++ b/src/stm/ao_arch_funcs.h @@ -366,6 +366,22 @@ static inline void ao_arch_restore_stack(void) { #define HAS_SAMPLE_PROFILE 0 #endif +#if DEBUG +#define HAS_ARCH_VALIDATE_CUR_STACK 1 + +static inline void +ao_validate_cur_stack(void) +{ + uint8_t *psp; + + asm("mrs %0,psp" : "=&r" (psp)); + if (ao_cur_task && + psp <= ao_cur_task->stack && + psp >= ao_cur_task->stack - 256) + ao_panic(AO_PANIC_STACK); +} +#endif + #if !HAS_SAMPLE_PROFILE #define HAS_ARCH_START_SCHEDULER 1 diff --git a/src/stm/ao_timer.c b/src/stm/ao_timer.c index 8db62e76..91ede84b 100644 --- a/src/stm/ao_timer.c +++ b/src/stm/ao_timer.c @@ -41,6 +41,7 @@ volatile __data uint8_t ao_data_count; void stm_systick_isr(void) { + ao_validate_cur_stack(); if (stm_systick.csr & (1 << STM_SYSTICK_CSR_COUNTFLAG)) { ++ao_tick_count; #if HAS_TASK_QUEUE |