Re: Help in loading modules

[Sumitra Sharma <sumitraartsy@gmail.com>]

On Sun, Mar 12, 2023 at 06:25:21PM -0700, Ira Weiny wrote:
> Sumitra Sharma wrote:
> > More information:
> > 
> > Upon running the "dmesg" it shows 
> > ##
> > BPF: 	Invalid name_offset:2154618
> > [ 2905.429687] failed to validate module [pi433] BTF: -22
> > ##
> 
> Good start.  I did some digging.
> 
> $ git grep "failed to validate module"
> kernel/bpf/btf.c:                               pr_warn("failed to validate module [%s] BTF: %ld\n",
> 
> 
> kernel/bpf/btf.c:
> ...
>                         if (!IS_ENABLED(CONFIG_MODULE_ALLOW_BTF_MISMATCH)) {
>                                 pr_warn("failed to validate module [%s] BTF: %ld\n",
>                                         mod->name, PTR_ERR(btf));
>                                 err = PTR_ERR(btf);
> 			} else {
> ...
> 
> 
> $ git grep BTF_MISMATCH
> kernel/bpf/btf.c:               if (env->btf->base_btf && IS_ENABLED(CONFIG_MODULE_ALLOW_BTF_MISMATCH))
> kernel/bpf/btf.c:               if (env->btf->base_btf && IS_ENABLED(CONFIG_MODULE_ALLOW_BTF_MISMATCH))
> kernel/bpf/btf.c:                       if (!IS_ENABLED(CONFIG_MODULE_ALLOW_BTF_MISMATCH)) {
> lib/Kconfig.debug:config MODULE_ALLOW_BTF_MISMATCH
> 
> 
> lib/Kconfig.debug:
> ...
> config MODULE_ALLOW_BTF_MISMATCH
>         bool "Allow loading modules with non-matching BTF type info"
>         depends on DEBUG_INFO_BTF_MODULES
>         help
>           For modules whose split BTF does not match vmlinux, load without
>           BTF rather than refusing to load. The default behavior with
>           module BTF enabled is to reject modules with such mismatches;
>           this option will still load module BTF where possible but ignore
>           it when a mismatch is found.
> ...
> 
> For more information on BTF:
> 
> https://docs.kernel.org/bpf/btf.html
> 
> Are you building this module in the same place as the running kernel?  It would
> probably be easier to do so.
> 
> Ira
>

Hi Ira,

What is the solution to this?

Regards,

Sumitra

> > 
> > Also I checked under "/lib/modules/`uname -r`" in the "modules.dep" file it do contains the  "kernel/drivers/staging/pi433/pi433.ko:".
> > 
> > I also tried running "sudo insmod ./kernel/drivers/staging/pi433/pi433.ko" which again prints the error:
> > 
> > ##
> > insmod: ERROR: could not insert module ./kernel/drivers/staging/pi433/pi433.ko: Invalid parameters
> > ##
> > 
> > Other than these I also checked the ".config" which contains: 
> > 
> > ##
> > CONFIG_SPI=y
> > CONFIG_STAGING=y
> > CONFIG_PI433=m
> > ##
> > 
> > where the module dependencies were given as 
> > 
> > Symbol: PI433 [=m]                                                                                               │  
> >   │ Type  : tristate                                                                                                 │  
> >   │ Defined at drivers/staging/pi433/Kconfig:2                                                                       │  
> >   │   Prompt: Pi433 - a 433MHz radio module for Raspberry Pi                                                         │  
> >   │   Depends on: STAGING [=y] && SPI [=y]                                                                           │  
> >   │   Location:                                                                                                      │  
> >   │     -> Device Drivers                                                                                            │  
> >   │       -> Staging drivers (STAGING [=y])                                                                          │  
> >   │ (1)     -> Pi433 - a 433MHz radio module for Raspberry Pi (PI433 [=m])  
> >  
> > 
> 
>