CPU busy, the littevGl may be crash

How-to
1

Hi
my project always crash when the cpu is busy, the core dump strace is below,

#0 0xaaaaaaaaaaaaaaaa in ?? ()
#1 0x0000000000436bf8 in lv_refr_obj (obj=0x592298 <work_mem_int+3448>, mask_ori_p=0x7f985cf760)
at /AA-GIT/UCM630X/Modules_RK/gui_code/lvgl/src/lv_core/lv_refr.c:517
#2 0x0000000000436cfc in lv_refr_obj (obj=0x591a4c <work_mem_int+1324>, mask_ori_p=0x7f985cf7c0)
at /AA-GIT/UCM630X/Modules_RK/gui_code/lvgl/src/lv_core/lv_refr.c:547
#3 0x0000000000436cfc in lv_refr_obj (obj=0x5917ac <work_mem_int+652>, mask_ori_p=0x7f985cf858)
at /AA-GIT/UCM630X/Modules_RK/gui_code/lvgl/src/lv_core/lv_refr.c:547
#4 0x0000000000436a64 in lv_refr_obj_and_children (top_p=0x5917ac <work_mem_int+652>, mask_p=0x7f985cf858)
at /AA-GIT/UCM630X/Modules_RK/gui_code/lvgl/src/lv_core/lv_refr.c:459
#5 0x0000000000436894 in lv_refr_area_part (area_p=0x591670 <work_mem_int+336>)
at /AA-GIT/UCM630X/Modules_RK/gui_code/lvgl/src/lv_core/lv_refr.c:397
#6 0x000000000043675c in lv_refr_area (area_p=0x591670 <work_mem_int+336>)
at /AA-GIT/UCM630X/Modules_RK/gui_code/lvgl/src/lv_core/lv_refr.c:353
#7 0x00000000004363cc in lv_refr_areas () at /AA-GIT/UCM630X/Modules_RK/gui_code/lvgl/src/lv_core/lv_refr.c:278
#8 0x0000000000435e18 in lv_disp_refr_task (task=0x591968 <work_mem_int+1096>)
at /AA-GIT/UCM630X/Modules_RK/gui_code/lvgl/src/lv_core/lv_refr.c:171
#9 0x000000000044a73c in lv_task_exec (task=0x591968 <work_mem_int+1096>)
at /AA-GIT/UCM630X/Modules_RK/gui_code/lvgl/src/lv_misc/lv_task.c:362
#10 0x000000000044a038 in lv_task_handler ()
at /AA-GIT/UCM630X/Modules_RK/gui_code/lvgl/src/lv_misc/lv_task.c:132
#11 0x0000000000412d04 in litteVGlHandler_thread (data=0x0) at main.cpp:563
#12 0x0000007f9a4a10e8 in start_thread ()
from /home/xp/UCM630XDebug/UCM630X_V1_0_2_1/rootfs/lib/libpthread-2.26.so
#13 0x0000007f99f8392c in thread_start () at …/sysdeps/unix/sysv/linux/aarch64/clone.S:78

please give me some advise to find what happend? thanks

2

the littevGL verison is 6.1

3

I’d suggest figuring out why it ends up executing at 0xaaaaaaaaaaaaaaaa. This smells like memory corruption.

4

Seing multiple 0xaa is a sign of using uninitialized pointer from an lv_obj, as lv_mem_alloc() memsets the freshly allocated space by 0xaa #if LV_MEM_ADD_JUNK.

Indeed, lv_refr.c:517 is
obj->design_cb(obj, &obj_ext_mask, LV_DESIGN_DRAW_MAIN);
so it’s an attempt to refresh an object which hasn’t set design_cb.

Evan, can you please show us what are you trying to draw?

JW

PS. Reminded me of what have I seen when investigating Lv_tabview_create() with copy does not initialize ext->tab_cnt

5

Just draw one page and image ,and some text label, some code like here:
if(bg_img == NULL)
{
#ifdef USE_SRC_IMAGE
bg_img = lv_img_create(lv_scr_act(), NULL);
if(page == PAGE_HOME)
lv_img_set_src(bg_img, &bg_1);
else
lv_img_set_src(bg_img,&bg_2);

     lv_obj_align(bg_img, NULL, LV_ALIGN_CENTER, 0, 0);
     lv_obj_set_drag(bg_img, true);
     lv_obj_set_size(bg_img, LV_HOR_RES, LV_VER_RES);

#else
/Create a simple base object/
bg_img = lv_obj_create(lv_scr_act(), NULL);
lv_obj_set_size(bg_img, LV_HOR_RES, LV_VER_RES);
lv_obj_set_style(bg_img, &bg_style);
lv_obj_align(bg_img, NULL, LV_ALIGN_IN_TOP_MID, 0, 0);
#endif
}
#if 1
/if the line is 1 ,the page should recreate,and the prev display need clear/
if(info_page !=NULL && line == 1)
{
lv_obj_del(info_page); //clear
info_page = lv_page_create(lv_scr_act(), NULL);
lv_obj_set_size(info_page, LV_HOR_RES, LV_VER_RES);
lv_obj_align(info_page, NULL, LV_ALIGN_CENTER, 0, 0);
lv_page_set_style(info_page, LV_PAGE_STYLE_BG, &menu_bg_style);
lv_page_set_style(info_page, LV_PAGE_STYLE_SCRL, &menu_bg_style);
lv_page_set_style(info_page, LV_PAGE_STYLE_SB, &menu_bg_style);
lv_page_set_sb_mode(info_page, LV_SB_MODE_AUTO);
}

/*Create a page*/
if(info_page == NULL)
{
    info_page = lv_page_create(lv_scr_act(), NULL);
    lv_obj_set_size(info_page, LV_HOR_RES, LV_VER_RES);
    lv_obj_align(info_page, NULL, LV_ALIGN_CENTER, 0, 0);
    lv_page_set_style(info_page, LV_PAGE_STYLE_BG, &menu_bg_style);           /*Set the scrollbar style*/
    lv_page_set_style(info_page, LV_PAGE_STYLE_SCRL, &menu_bg_style);           /*Set the scrollbar style*/
    lv_page_set_style(info_page, LV_PAGE_STYLE_SB, &menu_bg_style);           /*Set the scrollbar style*/
    lv_page_set_sb_mode(info_page, LV_SB_MODE_AUTO);                     /*Show scroll bars is scrolling is possible*/
}

lv_obj_t *label;

/*display the line content*/
label = lv_label_create(info_page, NULL);
//lv_obj_set_pos(label, 14, FONT_SIZE*(line-1)+LINE_SPACE*line);
if(page == PAGE_HOME)
    lv_label_set_style(label, LV_LABEL_STYLE_MAIN,&menu_bg_style);
else
    lv_label_set_style(label, LV_LABEL_STYLE_MAIN,&info_page_style);
lv_label_set_text(label, contentString);
lv_obj_align(label, bg_img,LV_ALIGN_IN_TOP_LEFT, 14, FONT_SIZE*(line-1)+LINE_SPACE*line);


/*display the line info*/
label = lv_label_create(info_page, NULL);
lv_label_set_style(label, LV_LABEL_STYLE_MAIN,&menu_sel_style);
lv_label_set_text(label, infoString);
lv_obj_align(label, bg_img,LV_ALIGN_IN_TOP_RIGHT, -14, FONT_SIZE*(line-1)+LINE_SPACE*line);

Can i define the LV_MEM_ADD_JUNK to 0?

6

static void* tick_thread(void * data)
{
(void)data;

while(1) {
    //SDL_Delay(5);   /*Sleep for 5 millisecond*/
    usleep(5000);
    //printf("tick_thread run\n");
    lv_tick_inc(5); /*Tell LittelvGL that 5 milliseconds were elapsed*/
}

return 0 ;

}

static void* litteVGlHandler_thread(void * data)
{
(void)data;

while(1) {
    //printf("tick_thread run\n");
    lv_task_handler();
    usleep(5000);
}

return 0 ;

}
int main(int argc, const char **argv)
{
pthread_t tickThread;
pthread_attr_t d;
sched_param param;

pthread_attr_init(&d);
pthread_attr_setstacksize(&d, THREAD_STACKSIZE);
pthread_attr_setdetachstate(&d, PTHREAD_CREATE_DETACHED);

/*set priority*/
pthread_attr_setschedpolicy(&d,SCHED_RR);
pthread_attr_getschedparam(&d, &param);
param.sched_priority=1;
pthread_attr_setschedparam(&d, &param);
pthread_create(&tickThread, &d, tick_thread, NULL); // LCD navigation and display.
if(lv_sdk_Init())
{
    cout << "[LCD] initFT4222 init failed !" << endl;
}
create_lv_style();

pthread_t handlerThread;
pthread_attr_t f;
pthread_attr_init(&f);
pthread_attr_setschedpolicy(&f,SCHED_RR);
pthread_attr_getschedparam(&f, &param);
param.sched_priority=0;
pthread_attr_setschedparam(&f, &param);
pthread_attr_setstacksize(&f, THREAD_STACKSIZE);
pthread_attr_setdetachstate(&f, PTHREAD_CREATE_DETACHED);
pthread_create(&handlerThread, &f, litteVGlHandler_thread, NULL); // update the lcd

while (1)
{
    /* update the network info */
    usleep(5000);

}

return 0;

}

Please help me to check the tick hander and task_handler ,thanks!

7

(gdb) p obj
$5 = {par = 0x591a4c <work_mem_int+1324>, child_ll = {n_size = 128, head = 0x0, tail = 0x0}, coords = {x1 = 0,
y1 = 0, x2 = 100, y2 = 66}, event_cb = 0xaaaaaaaaaaaaaaaa, signal_cb = 0xaaaaaaaaaaaaaaaa,
design_cb = 0xaaaaaaaaaaaaaaaa, ext_attr = 0xaaaaaaaaaaaaaaaa, style_p = 0xaaaaaaaaaaaaaaaa,
group_p = 0xaaaaaaaaaaaaaaaa, ext_click_pad = {x1 = 0, y1 = 0, x2 = 0, y2 = 0}, click = 0 ‘\000’,
drag = 1 ‘\001’, drag_throw = 0 ‘\000’, drag_parent = 1 ‘\001’, hidden = 0 ‘\000’, top = 1 ‘\001’,
opa_scale_en = 0 ‘\000’, parent_event = 1 ‘\001’, drag_dir = 2 ‘\002’, reserved = 42 '’,
protect = 170 ‘\252’, opa_scale = 170 ‘\252’, ext_draw_pad = 0, realign = {base = 0x0, xofs = 0, yofs = 0,
align = 0 ‘\000’, auto_realign = 0 ‘\000’, origo_align = 1 ‘\001’}, user_data = 0xaaaaaaaaaaaaaaaa}

8

other refresh page thread statck,
#0 lv_ll_init (ll_p=0x591a54 <work_mem_int+1332>, node_size=128)
at /AA-GIT/UCM630X/Modules_RK/gui_code/lvgl/src/lv_misc/lv_ll.c:52
#1 0x00000000004321e0 in lv_obj_create (parent=0x5917ac <work_mem_int+652>, copy=0x0)
at /AA-GIT/UCM630X/Modules_RK/gui_code/lvgl/src/lv_core/lv_obj.c:222
#2 0x0000000000443864 in lv_cont_create (par=0x5917ac <work_mem_int+652>, copy=0x0)
at /AA-GIT/UCM630X/Modules_RK/gui_code/lvgl/src/lv_objx/lv_cont.c:69
#3 0x00000000004460e0 in lv_page_create (par=0x5917ac <work_mem_int+652>, copy=0x0)
at /AA-GIT/UCM630X/Modules_RK/gui_code/lvgl/src/lv_objx/lv_page.c:79
#4 0x0000000000417d44 in lcdFrameBuffer::build_home_info_page (this=0x349bc390, page=PAGE_HOME,
contentString=0x349bc680 “Model”, infoString=0x349bc880 “UCM6302 V1.2B”, line=1) at main.cpp:2387
#5 0x000000000041b730 in lcdFrameBuffer::buildPage (this=0x349bc390, page=PAGE_HOME, line=2) at main.cpp:3166
#6 0x00000000004204f8 in lcdFrameBuffer::writeFrameBuffer (this=0x349bc390, page=PAGE_HOME, line=1)
at main.cpp:4100
#7 0x0000000000416678 in refresh (id=0x0) at main.cpp:1803
#8 0x0000007f7adc50e8 in start_thread ()
from /home/xp/UCM630XDebug/UCM630X_V1_0_2_1/rootfs/lib/libpthread-2.26.so
#9 0x0000007f7a8a792c in thread_start () at …/sysdeps/unix/sysv/linux/aarch64/clone.S:78

9

Can you show also the parent (dereference obj.par)?

I don’t see anything suspicious in the code but I am not an LVGL expert.

JW