[Buildroot] usb_modeswitch and lsusb yield Segmentation fault

[Gustavo Zacarias <gustavo@zacarias.com.ar>]

On 12/09/2012 08:06 PM, Sagaert Johan wrote:

> Hi
>  
> I am using the latest git pull of buildroot.
>  
> Both usb_modeswitch and lsusb fail on execute.
>  
> # lsusb
> Segmentation fault
> # usb_modeswitch
> Segmentation fault
>  
> Can sombody verify this on a real target ?
>  
> (i am using a karo tx53 module running kernel 3.4.21)
>  
> I suspect it has something to do with libusb.

Hi.
I recall a similar problem with earlier (0.9.32ish or less) versions of
uClibc with NPTL, which toolchain are you using?

> Looking at the makefile of usb_modeswitch, it seems to link
> against libusb.so
> It looks this is pointing to libusb-compat-0.1.4
>  
> In the source code of usb_modeswitch there is a line (1896)  saying : 
> ....based on libusb0 (0.1.12 and above ...)
>  
> So something seems to be wrong (libusb-compat-0.1.4 is the latest
> version) , should usb_modeswitch be linked to libusb-1.0.9 instead. ?
>  
> I will try to link against to the other usblib, as soon as my current
> build finishes ...
>  
> I suspect the lsusb problem is similar

There was an older API libusb (libusb-0*) which usb_modeswitch uses, and
there is a newer API libusb (libusb-1*) now.
libusb-compat is a compatibility layer to use the new one (libusb-1*)
with applications that expect the old API without the need for both.
I haven't seen any issues with it rather than the old misbehaving NPTL
threading from older uClibc versions.
And you won't be able to link against libusb-1* without some source code
tweaking.
Regards.