Why are functions loaded at aligned addresses in x86 Linux for elf executables?

Posted by user344787 on Stack Overflow See other posts from Stack Overflow or by user344787
Published on 2010-05-19T06:48:05Z Indexed on 2010/05/19 6:50 UTC
Read the original article Hit count: 305

Filed under:

linux

|

elf

|

loading

Hi,

I've been looking at Linux elf executables on x86, mostly using IDA but also gdb. One thing I've noticed is functions are always loaded at word aligned addresses? Anybody knows the reason of that? I am not aware of any requirement of x86 instructions to start at aligned addresses. And it cannot be due to page alignment cause the page boundary can still be anywhere within the function.

I would appreciate any insight at all.

Thanks.

© Stack Overflow or respective owner

Related posts about linux

apt-get install and update fail

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I've got a problem with apt-get update and apt-get install ... commands . every time update or installing fails and errors are : Get:1 http://dl.google.com stable Release.gpg [198B] Ign http://dl.google.com/linux/chrome/deb/ stable/main Translation-en_US Get:2 http://dl… >>> More
kernel module compiling error

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
sh@ubuntu:/home/ccpp/helloworld$ make gcc-4.6 -O2 -DMODULE -D_KERNEL_ -W -Wall -Wstrict-prototypes -Wmissing-prototypes -isystem /lib/modules/`uname -r`/build/include -c -o hello-1.o hello-1.c hello-1.c:4:0: warning: "MODULE" redefined [enabled by default] <command-line>:0:0: note: this is… >>> More
Build-Essentials installation failing

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I am having trouble accessing the several critical header files that show to be a part of the build process. The "Ubuntu Software Center" shows "Build Essentials" as installed: Next I did the following two commands, which did not improve the problem: ~$ sudo apt-get install build-essential [sudo]… >>> More
Updating Debian kernel

as seen on Super User - Search for 'Super User'
I'm trying to update my Debian machine to 2.6.32-46 (which is the new stable). However, after doing apt-get update my apt-cache search linux-image shows me: linux-headers-2.6.32-5-486 - Header files for Linux 2.6.32-5-486 linux-headers-2.6.32-5-686-bigmem - Header files for Linux 2.6.32-5-686-bigmem linux-headers-2… >>> More
Serial connection over a single USB cable (Windows to linux, or linux to linux)

as seen on Server Fault - Search for 'Server Fault'
I'm helping out with a project for an embedded device that only has USB and no serial. This device is running Linux. These days, when we need to connect to a serial port on a device we typically use a USB to serial adapter (on something like a phone system or a load balancing device, etc). I would… >>> More

Related posts about elf

Error Installing MS office in ubuntu 13.04

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
While I am installing ms office 10 or 13 using wine it says the following: Unhandled exception: 0xc06d007e in 32-bit code (0x7b83ae0b). Register dump: CS:0023 SS:002b DS:002b ES:002b FS:0063 GS:006b EIP:7b83ae0b ESP:0a6cd3f8 EBP:0a6cd45c EFLAGS:00000287( - -- I S - -P-C) EAX:7b826449 EBX:7b8b0000… >>> More
LIMBO fails on startup with Internal errors - invalid parameters received

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I installed LIMBO from the Humble Bundle V and as far as I am aware, this has wine packaged with it (I also installed the latest from the repo's in case is was because of that). However the game doesn't even start and fails with the message: Wine Program Error Internal errors - invalid parameters… >>> More
Installing Age of Empires II using PlayOnLinux doesn't work?

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I have tried installing age of empires 2 using PlayOnLinux, the installation appeared to go fine but when I try and open the game it says there is a serious fault. The error report is below, unfortunately this doesn't mean alot to me, I was wondering if you could help, a) By highlighting the problem… >>> More
How can I read kindle book under xfce(ubuntu)? (using chromebook)(wine not working)

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I'm using chromebook, dual booting xfce(ubuntu) and cr os. The ebook I bought on amazon is not supported on kindle cloud reader. (Under xfce)I downloaded wine and tried installing kindle for pc under wine, and after couples of times of trials, it always said installation error and could not install… >>> More
FreeBSD 8.1 64bit logrotate - ELF interpreter /libexec/ld-elf-so.1 not found

as seen on Server Fault - Search for 'Server Fault'
I am trying to get logrotate running on a FreeBSD 8.1 virtual machine. I installed the logrotate with pkg_add, I have created the logrotate.config file and also run: mkdir /var/lib/ touch /var/lib/logrotate.status Now when I do: /usr/local/sbin/logrotate -d /usr/local/etc/logrotate.conf I get… >>> More