why linux ELF base address is 0x8048000?

why linux ELF base address is 0x8048000?

[pei lin]

hi,
   why linux ELF base address is 0x8048000? we can use ld to change
the base address or linker script.BUT why default is 0x8048000? There
must be some reasons or history i don't know. Could u give me an
advice? Thx.


Best Regards.

P.L

Re: why linux ELF base address is 0x8048000?

[pei lin]

The article i read, but it does't explain my question about why linux
loads all elfs to this base address.

2009/2/4 Chris Evans <teknopup@gmail.com>:
> http://www.linux-tutorial.info/modules.php?name=MContent&pageid=327
>
>
> On Tue, Feb 3, 2009 at 1:25 AM, pei lin <telent998@gmail.com> wrote:
>>
>> hi,
>>   why linux ELF base address is 0x8048000? we can use ld to change
>> the base address or linker script.BUT why default is 0x8048000? There
>> must be some reasons or history i don't know. Could u give me an
>> advice? Thx.
>>
>>
>> Best Regards.
>>
>> P.L
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-assembly"
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>

Re: why linux ELF base address is 0x8048000?

[Brian Raiter]

>   why linux ELF base address is 0x8048000? we can use ld to change
> the base address or linker script.BUT why default is 0x8048000?
> There must be some reasons or history i don't know.

As far as I can tell, the reason is that this was the address used by
SVR4, which was the first release of Unix to use ELF executables.

The reason that SVR4 chose that particular address is that the stack
top was located at 0x08000000 (growing downward, of course), and then
the area between 0x08000000 and 0x08048000 was reserved for libc and
possibly other system service code.

b

Re: why linux ELF base address is 0x8048000?

[pei lin]

yeah,that explains some reason. But between 0x08000000 and 0x08048000
should be some other reason for X86 architecture . <<The linker and
loader>> said that "permitting most programs to use a single
second-level page table."

But i can not understand it very well.

Lin

2009/2/5 Brian Raiter <breadbox@muppetlabs.com>:
>>   why linux ELF base address is 0x8048000? we can use ld to change
>> the base address or linker script.BUT why default is 0x8048000?
>> There must be some reasons or history i don't know.
>
> As far as I can tell, the reason is that this was the address used by
> SVR4, which was the first release of Unix to use ELF executables.
>
> The reason that SVR4 chose that particular address is that the stack
> top was located at 0x08000000 (growing downward, of course), and then
> the area between 0x08000000 and 0x08048000 was reserved for libc and
> possibly other system service code.
>
> b
>