[SOLVED] First time building a kernel, what processor family do I choose for my T42?
Linux - NewbieThis Linux forum is for members that are new to Linux.
Just starting out and have a question?
If it is not in the man pages or the how-to's this is the place!
Welcome to LinuxQuestions.org, a friendly and active Linux Community.
You are currently viewing LQ as a guest. By joining our community you will have the ability to post topics, receive our newsletter, use the advanced search, subscribe to threads and access many other special features. Registration is quick, simple and absolutely free. Join our community today!
Note that registered members see fewer ads, and ContentLink is completely disabled once you log in.
If you have any problems with the registration process or your account login, please contact us. If you need to reset your password, click here.
Having a problem logging in? Please visit this page to clear all LQ-related cookies.
Introduction to Linux - A Hands on Guide
This guide was created as an overview of the Linux Operating System, geared toward new users as an exploration tour and getting started guide, with exercises at the end of each chapter.
For more advanced trainees it can be a desktop reference, and a collection of the base knowledge needed to proceed with system and network administration. This book contains many real life examples derived from the author's experience as a Linux system and network administrator, trainer and consultant. They hope these examples will help you to get a better understanding of the Linux system and that you feel encouraged to try out things on your own.
Click Here to receive this Complete Guide absolutely free.
First time building a kernel, what processor family do I choose for my T42?
So there's always ever been "484" or "686" for preconfigured kernels, to my knowledge. I'm building a kernel for the first time on my own for a slackware 14 install, and in the Kernel Configuration, there's a processor family list with 486 already selected, but my specific processor for the T42 Thinkpad I'm using is a Pentium M which is also an option on the list.
My confusion comes from the 486 option stating
This is the processor type of your CPU
and the Pentium M option stating
Select this for Intel Pentium M (not Pentium-4 M) notebook chips.
My processor is definitely Pentium M, but the 486 processor has worked fine in the past. Further, the choice will also wind up affecting certain packages that are cpu-family specific and I don't know if something that works for 486 will work if I choose Pentium M.
As you can see, I'm quite confused. Can anyone offer any insight here?
In general, either choice should be safe. You might see slightly better performance if you build for the 686 or Pentium M architecture, but it will probably be pretty minor. You should not see any software compatibility problems regardless of which architecture you choose. The only difference is which assembler instructions the compiler will be allowed to generate when building the kernel. A kernel containing only 486 compatible instructions will happily run userspace programs containing instructions introduced with more modern processors. The only thing is that a 32 bit kernel can't run 64 bit user space software, generally, but since the Pentium M is a 32 bit chip and can't run 64 bit software anyways, this should not be a big concern.
There is no harm in using the 486, as it should run on most any i486 and later processor. If you are sure that your processor type, then compiling it for that specific type could give you better performance. You just have to realize that that kernel will not run on other processor types like the 486 built kernel can.
<edit> btmiller's post is more concise. I must have been writing mine when that was posted. </edit>
If I'm building it for a Pentium M processor, what difference would it make if the Pentium M kernel wouldn't run on other processors?
Basicly, I think of disaster recovery. If your Pentium-M got fried and the replacement that you find that is compatable with your motherboard/bios isn't a Pentium-M, you will have to have a compatable kernel to boot. A way to ensure that is to keep a 486 one installed even though using the Pentium-M kernel. Also, for disaster recovery, a copy of the install medium can be of real help (ie, kernel won't boot).