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 Post subject: ELF 86_64 Relocatable file :: relocation issue
PostPosted: Sun Jun 26, 2022 11:25 am 
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Hello everyone,

I just started writing a 64bit OS.
I was trying to write a module loader.
https://github.com/AdeRegt/SanderOS64/b ... c/module.c
^ ^ ^ ^ this is my attempt

https://github.com/AdeRegt/SanderOS64/b ... keyboard.c
^ ^ ^ ^ this is an example driver

now, I expect the system to print out "Hello, world!".
But the system is printing out strange characters.
What am I doing wrong? I think something with the relocation is not going well.

Thank you in advantage.


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 Post subject: Re: ELF 86_64 Relocatable file :: relocation issue
PostPosted: Sun Jun 26, 2022 1:42 pm 
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You seem to be just reading the file into memory rather than loading the sections to the appropriate addresses.


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 Post subject: Re: ELF 86_64 Relocatable file :: relocation issue
PostPosted: Sun Jun 26, 2022 1:45 pm 
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Yeah, I want to dynamically load the program. So the program must be loaded at any place that I wan.


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 Post subject: Re: ELF 86_64 Relocatable file :: relocation issue
PostPosted: Sun Jun 26, 2022 2:13 pm 
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So you are compiling the code as position-independent?


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 Post subject: Re: ELF 86_64 Relocatable file :: relocation issue
PostPosted: Sun Jun 26, 2022 2:31 pm 
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Exactly


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 Post subject: Re: ELF 86_64 Relocatable file :: relocation issue
PostPosted: Sun Jun 26, 2022 2:46 pm 
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OK. I must have missed the switch for that in your compile command.


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 Post subject: Re: ELF 86_64 Relocatable file :: relocation issue
PostPosted: Sun Jun 26, 2022 4:25 pm 
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What is the address of the "hello world" string?

What address is being passed to k_printf?


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 Post subject: Re: ELF 86_64 Relocatable file :: relocation issue
PostPosted: Mon Jun 27, 2022 3:58 pm 
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Thank you for the answer,

This was indeed the problem, I solved the issue now, thanks allot!


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