On Tue, Mar 17, 2020 at 05:57:05PM +0100, Oliver Graute wrote: > On 16/03/20, Marco Felsch wrote: > > On 20-03-16 18:30, Andy Shevchenko wrote: > > > On Mon, Mar 16, 2020 at 03:57:36PM +0100, Oliver Graute wrote: > > > > On 02/03/20, Oliver Graute wrote: > > > > > Hello, > > > > > > > > > > I have on of these FT6336G Touch Panels here and I try to get it work > > > > > with the ft6236 driver. It comes up with model identification "0x11". So > > > > > I added that identification to the switch case in > > > > > edt_ft5x06_ts_identify(). But it crashes directly after the probe with a > > > > > corrupted stack. No clue why. Some ideas? > > > > > > > > I still observe sometimes crashes with ft6236G. When it occurs it is > > > > always a stack corruption in the probe function on bootup. > > > > > > > > No clue why stack is corrupted sometimes. Is this related to the buggy > > > > revision field? > > > > > > > > Some further suggestions for debugging this? > > > > > > Are you sure you have proper I²C bus settings on electrical level > > > (pull-up strength, line capacitance, etc.)? > > > > > > > [ 3.806780] edt_ft5x06 1-0038: Model "EP0110M09", Rev. "�", 0x0 sensors > > > > [ 3.808468] at24 2-0050: 2-0050 supply vcc not found, using dummy regulator > > > > [ 3.814864] DEBUG: edt_ft5x06_ts_probe 1201 > > > > [ 3.826215] DEBUG: edt_ft5x06_ts_probe 1211 > > > > [ 3.830512] DEBUG: edt_ft5x06_ts_probe 1214 > > > > [ 3.834904] input: EP0110M09 as /devices/platform/bus@5a000000/5a820000.i2c/i2c-1/1-0038/input/input0 > > > > [ 3.844164] at24 2-0050: 4096 byte 24c32 EEPROM, writable, 1 bytes/write > > > > [ 3.844264] DEBUG: edt_ft5x06_ts_probe 1222 > > > > [ 3.850919] i2c i2c-2: LPI2C adapter registered > > > > [ 3.855187] edt_ft5x06 1-0038: EDT FT5x06 initialized: IRQ 55, WAKE pin -1, Reset pin -1. > > > > > > > [ 3.867878] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: edt_ft5x06_ts_probe+0x5c4/0xb00 > > > > > > Maybe you can look at the assembly to see how compiler puts variables on stack. Also enabling KASAN might help. > > > > This would be the easiest way to debug such failures and since ARMv8 > > support it you just need to enable it =) > > ok, I enabled KASAN and I got the following trace: Nice. I think it has nothing to do with touch screen. By the way... > [ 0.000000] Linux version 5.6.0-rc1-next-20200214-00057-g9e78f1560095-dirty (alarm@imx8qm) (gcc version 9.2.0 (GCC)) #100 SMP PREEMPT Tue Mar 17 15:54:17 UTC 2020 May you try the latest and greatest release candidate, i.e. v5.6-rc6 w/o any patches applied? Then, enable only touchscreen and try again. Otherwise it's probably good to inform ARM + kasan maintainers about the issue. -- With Best Regards, Andy Shevchenko
