A call does not work
Posted: Sun Aug 10, 2014 5:54 am
Hello everybody.
I have a little problem with my OS. In the initial loading of my OS, GRUB loads a initrd (Initial RAM Disk) which contains a plain binary that I copy to another address in the memory which is controled by the OS and it's preparated to run applications. After I copy the binary, I try to call it, because I know where the entry point is. Besides, to know if the call has properly worked, the code writes in an address that I also know some numbers that I can read from the debugger.
The code is something like that:
My OS:
Binary
PS. My English is not my mother tongue and, as you all can see, my level isn't too high so, sorry 
PS2. If everyone needed more information, or code, do not doubt to ask me for it.
I have a little problem with my OS. In the initial loading of my OS, GRUB loads a initrd (Initial RAM Disk) which contains a plain binary that I copy to another address in the memory which is controled by the OS and it's preparated to run applications. After I copy the binary, I try to call it, because I know where the entry point is. Besides, to know if the call has properly worked, the code writes in an address that I also know some numbers that I can read from the debugger.
The code is something like that:
My OS:
Code: Select all
void (*call)(void* param) = ((void(*)(void* param)) address; // The address is in the MB 16 and, yes, it's mapped.
call(data); // where data is a struct which contains some information that application needs. Besides, there are also a CRC so
// I can check whether the code have done its work fine. The problem is that the code seems not to work (in fact, it seems
// that it is not called at all ) because the structure isn't modified (when the struct. must have been changed). Moreover,
// when I look at the address I said before, there are nothing.
Code: Select all
unsigned int* address2check = (unsigned int*)0x1400000; // Again, it's mapped and there are no mmio mapped to that address.
*addres2chechk = 0x1234567; // A random number I put.
// Then I use the struct info and I modify its contents.
PS2. If everyone needed more information, or code, do not doubt to ask me for it.