CODEWITHSUNDEEP
android
dtbaker
dtbaker

Reputation: 4919

Custom Android kernel - unable to load kernel modules

I'm having issues loading kernel modules on Android, the kernel has been crosscompiled from a 64bit linux box. Kernel boots fine, it just wont load any modules (even bcm4329.ko for wifi)

The kernel and modules are flashed onto the device (HTC Desire) using CWM "install from zip" feature in recovery. 

root@android:/data # uname -a                                                  
Linux localhost 2.6.38.8-dtbaker2-ics+ #3 PREEMPT Sun May 5 18:50:10 EST 2013 armv7l GNU/Linux

trying to load module manually:

root@android:/system/lib/modules/dtbaker2-ics # ls -l 
-rw-rw-rw- root     root       287308 2013-05-05 08:50 bcm4329.ko
root@android:/system/lib/modules/dtbaker2-ics # depmod -a 
root@android:/system/lib/modules/dtbaker2-ics # modprobe bcm4329               
modprobe: 'dtbaker2-ics/bcm4329.ko': unknown symbol in module or invalid parameter
root@android:/system/lib/modules/dtbaker2-ics # insmod bcm4329.ko          
insmod: init_module 'bcm4329.ko' failed (No such file or directory)
root@android:/system/lib/modules/dtbaker2-ics # modinfo bcm4329.ko             
filename:       bcm4329.ko
license:        GPL v2
alias:          sdio:c*v02D0d4319*
alias:          sdio:c*v02D0d4329*
alias:          sdio:c*v02D0d0493*
alias:          sdio:c*v02D0d0492*
alias:          sdio:c*v02D0d0000*
depends:        
vermagic:       2.6.38.8-dtbaker2-ics+ preempt mod_unload ARMv7 
parm:           dhd_oob_gpio_num:DHD oob gpio number
parm:           clockoverride:SDIO card clock override

dmesg output after modprobe or insmod:

[ 1525.047424] bcm4329: Unknown symbol _GLOBAL_OFFSET_TABLE_ (err 0)

The /proc/config.gz output from my custom built kernel is identical to the output from a fresh install of this ICS ROM (bar the date).

A couple of forum posts mentioned SLAB/SLUB and module loading issues, so I even tried to rebuild the initial SLAB kernel (dtbaker-ics) with the SLUB option (dtbaker2-ics) and the identical problem exists.

Could this be a 64bit cross compilation issue? Is it weird that the kernel works fine but modules are not loaded?

Upvotes: 3

Views: 7251

Answers (1)

dtbaker
dtbaker

Reputation: 4919

Ah! "Unknown symbol _GLOBAL_OFFSET_TABLE_" error: https://groups.google.com/forum/?fromgroups=#!topic/android-kernel/dzEIOVuxtEo

I remembered early on I swapped to using prebuilt toolchain arm-linux-androideabi-4.4.3 instead of arm-eabi-4.4.0 because arm-eabi-4.4.0 did not work for me on 64bit ubuntu ( shrug )

As per the above google groups post, modified my kernel Makefile from this:

MODFLAGS        = -DMODULE -march=armv7-a -mfpu=vfpv3 -ftree-vectorize

to this:

MODFLAGS        = -DMODULE -march=armv7-a -mfpu=vfpv3 -ftree-vectorize -fno-pic

Then re-built the kernel modules:

make clean
make modules

and copied my new module back over to android, away she goes!

Upvotes: 4

Related Questions