Re: Regression: boot failure on AMD Elan TS-5500

From: H. Peter Anvin
Date: Tue Jul 15 2008 - 18:36:35 EST


Sean Young wrote:

When I bisected this issue between latest and 2.6.23 the issue seemed to be
here (round about 2.6.24-rc1). Trying to repeat the same things on latest just led to confusion.

So I've started from scratch with contemporary trees and found something very different.

2.6.25: works
2.6.25.5: works
2.6.25.6: broken
2.6.25.10: broken
2.6.26: works

Now the issue which was introduced in 2.6.25.6 is that a rdtsc will be done
even though this CPU does not support it (before console_init(), leaving
me with only one led for output!). This issue has been fixed in 2.6.26 but not in 2.6.25-stable.

The protected mode jump was just a red herring (or at least whatever was broken back then is fixed now); 2.6.26 is working fine and that's good enough for me.


Okay, that is good to know. We did move the jmp in pmjump.S for 2.6.26; even if it ended up being redundant I have to say I'm happier following the documented script, especially given the apparent recent documentation change on Intel's part about this.

-hpa
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