imx6Dp galcore crash running 2 qt5 applications

[vaudoitlaurent]

Hi,

on a board with an imx6DP, 2G DDR, we have 2 QT5 applications running.

One on a dual lvds channel display (ldb used), 1920*720

One on a hdmi display, 1920*1080

Applications runs well, and randomly, after a while we get a galcore crash with the message:

"DMA appears to be stuck at this address:

     0x6D765710

   dmaLow   = 0x48000000

   dmaHigh  = 0x00000701

   dmaState = 0x00000015

   and a dump of galcore memory.

   We have a 320M cma, and galdcore have a 128M.

   I've tried increasing cma to 512M (as we have 2G ddr) and galcore to 256M => Problem still appears

   I've also tried imx6 running at 792MHz instead of 996Mhz => problem reproduced

   VDDpu and VDDSoc semms correct

   Running 2 nxp graphic demo applications does not reproduced

   Running 2 qt5 webview applications does not reproduced

   We have a yocto kirkstone image, using a linux-fslc-imx 5.15.148 kernel from linux 5.15-2.2.x-imx branch

   I've tested galcore version  6.4.3.p4.6 and 6.4.3.p4.10, problem reproduced

   Running kmemleak, i see some memory leak in galcore module, but don't know if it is due to a problem in applications which does not free some object or in the driver

   Would you have some idea on what i could have a look to fix this crash?

   Could this be due to a wrong memory acces in the application, who would corrupt galcore contiguous memory pool?

   Thanks in advance for your help

   Regards

   Laurent

[vaudoitlaurent]

Hi, thanks for your answer,

i've allreadyu tried increasing/decrasing CMA between 512M and 256M, without success. I will try icreasing to 996 as you suggest.

when the problem occurs, cat /proc/meminfo does not show we run out of memory (i mean cma free is quite correct), so i don't think it is a cma meory issue.

I found on nxp forum a post mentionning the CONFIG_MX6_VPU_352M.

On my setup this is not activated. I am currently running a test with this config activated, and it seems it decrease the frequency of the problem.

If i understand  well this option, this will increase the VDDPu and de activate the busfreq driver.

Is it something i should go further on?

[Bio_TICFSL]

Hi,

I see some issue in galcore, are you working with module galcore or driver? I can not reproduce this issue but repeat I have 4GB of RAM, maybe this is related. also please try to test the latest BSP.

  Regards

[vaudoitlaurent]

Hi,

i use galcore as a module.

i've tried  6.4.3.p4.6 and 6.4.3.p4.10 version

Regards

Laurent

[Bio_TICFSL]

Hi,

correct! you may check if the driver fails please download and test the official BSP:

https://www.nxp.com/design/design-center/software/embedded-software/i-mx-software/embedded-linux-for...

Regards

[Bio_TICFSL]

Hello,

Just for the top of my head, try to move the DMAhigh address to more memory o less memory and try to change the CMA to 916M, this is a memory issue the graphics app must run. I tested to run two QT  app on 6.6.36 BSP and works ok without modify nothing just i have 4 GB of RAM

Regards