LinuxQuestions.org
Share your knowledge at the LQ Wiki.
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Distributions > Mandriva
User Name
Password
Mandriva This Forum is for the discussion of Mandriva (Mandrake) Linux.

Notices


Reply
  Search this Thread
Old 12-01-2004, 06:57 AM   #16
aus9
LQ 5k Club
 
Registered: Oct 2003
Location: Australia
Distribution: Devuan
Posts: 5,476

Rep: Reputation: Disabled

for us simple beings do we?

no lapic and noapic for kernel appends
if bios has some power options will it make a diff if we disable them oh gurus?
 
Old 12-01-2004, 07:09 AM   #17
TimMann
LQ Newbie
 
Registered: Nov 2004
Location: Palo Alto, California
Posts: 12

Rep: Reputation: 0
Quote:
Originally posted by opjose
I've seen many a kernel post to the effect that the noapic option should indeed shut off the local apic as well.
I haven't read enough code to be sure exactly how the two options interact, but I don't see anything on the path into detect_init_APIC that depends on the noapic option. Also, I can tell you how the hardware works: the ioapic requires a local apic on each CPU to talk to, so if you shut off the local apic, you necessarily have to shut them both off. However, a local apic can do some limited things without an ioapic. In fact, in a non-multiprocessor-capable system, there may be no ioapic, but the local apic can still be used. I think only the timer part of it is significantly useful without an ioapic.

Quote:
Also you've pretty much confirmed that the kernel is disregarding the nolapic parameter at boot, as all that patch does is to FORCE apic off totally.

Note that the patch does not seem to disable LOCAL apic, but rather it specifies no_apic ...

+ if (enable_local_apic != 1)
+ goto no_apic;

If Local APIC is not enabled on the command line explicitly, disable APIC altogether...
No, you are reading code way too superficially here. The whole function you are looking at is all about the LOCAL apic, even though it doesn't have the word "local" in every label and variable name. Check the message that is printed when you reach the label no_apic. The ioapic stuff is in io-apic.c.

Quote:
Sheez this fix is so simple! I wish Mandrake would include it in their release.

You may want to post it on their bugtracker as well as this seems to be a rather large problem which needs to be addressed. [/B]
Yes, I'll do that soon. It's a trivial backport from 2.6.9, so they shouldn't have any problem including it in an update kernel.
 
Old 12-01-2004, 07:21 AM   #18
TimMann
LQ Newbie
 
Registered: Nov 2004
Location: Palo Alto, California
Posts: 12

Rep: Reputation: 0
Quote:
Originally posted by aus9
for us simple beings do we?

no lapic and noapic for kernel appends
if bios has some power options will it make a diff if we disable them oh gurus?
Sorry, I don't understand the question. This thread is about one specific issue, where the local apic must not be enabled on certain machines, but some kernel versions try to do it anyway, and the "nolapic" option that is supposed to prevent this behavior doesn't work on some of those kernel versions.

I have no idea whether you have this issue or not. Your profile says you're running Slackware 10.0, and I have no clue what kernel that has. If you see "Local APIC disabled by BIOS -- reenabling" in your boot messages and you have lots of problems after that, maybe you have the issue.

If you do have the issue, the only solutions I know of at the moment are to (a) patch your kernel and recompile, or (b) reconfigure your kernel with some options turned off (sorry, I haven't dug up the details on which ones) and recompile, or (c) upgrade or downgrade to a kernel version that works -- a 2.6.9-based kernel should work, for example.
 
Old 12-01-2004, 07:25 AM   #19
opjose
Senior Member
 
Registered: Sep 2004
Location: Outlying D.C.
Distribution: Mandriva
Posts: 2,090

Rep: Reputation: 46
Quote:
Originally posted by TimMann
I haven't read enough code to be sure exactly how the two options interact, but I don't see anything on the path into detect_init_APIC that depends on the noapic option. Also, I can tell you how the hardware works: the ioapic requires a local apic on each CPU to talk to, so if you shut off the local apic, you necessarily have to shut them both off. However, a local apic can do some limited things without an ioapic. In fact, in a non-multiprocessor-capable system, there may be no ioapic, but the local apic can still be used. I think only the timer part of it is significantly useful without an ioapic.


Yeah, I don't doubt you... merely that a lot of contradictory posts appeared, probably from people who had not looked at the code.

Certainly I haven't had any reason to peruse the APIC code to date...

Quote:

No, you are reading code way too superficially here. The whole function you are looking at is all about the LOCAL apic, even though it doesn't have the word "local" in every label and variable name. Check the message that is printed when you reach the label no_apic. The ioapic stuff is in io-apic.c.
Ah!

I had assumed that it was calling another function... my bad.


Quote:
Yes, I'll do that soon. It's a trivial backport from 2.6.9, so they shouldn't have any problem including it in an update kernel.
PLEASE, PLEASE, PLEASE do so!

The shear amount of posts here about "Mandrake Freezing on boot" is enormous and seems to revolve around this issue.

This would be a very welcome fix indeed!!!
 
Old 12-01-2004, 07:26 AM   #20
aus9
LQ 5k Club
 
Registered: Oct 2003
Location: Australia
Distribution: Devuan
Posts: 5,476

Rep: Reputation: Disabled
TimMann

well spotted, I am a ho....I am getting a new computer soon as wanted to try out mdk.
Actually I will have a burner so may try out heaps but thats another story.
 
Old 12-02-2004, 12:23 AM   #21
TimMann
LQ Newbie
 
Registered: Nov 2004
Location: Palo Alto, California
Posts: 12

Rep: Reputation: 0
FYI, I've filed this bug in Mandrake's bugzilla at http://qa.mandrakesoft.com/show_bug.cgi?id=12561
 
Old 12-02-2004, 05:21 AM   #22
opjose
Senior Member
 
Registered: Sep 2004
Location: Outlying D.C.
Distribution: Mandriva
Posts: 2,090

Rep: Reputation: 46
Those Aholes:

Did you see the response?

Quote:
You can drop the theatrics (this problem has been known on cooker for quite a
while, but kernel maintainers changed during community), and test this boot ISO
image (for people for whom the issue affects installation):

http://plf.zarb.org/~bgmilne/10.1/bo...local-apic.iso

Since this didn't help on the machine I was testing on (but
http://plf.zarb.org/~bgmilne/10.1/bo...c-disabled.iso did), I didn't make it
available at the time (19 Oct or so).

Of course, we would still need updated kernel packages ... but I wonder if
anyone has tried booting an smp-kernel on the affected machines.
And MY response to this stupidity!

Quote:
Re: http://qa.mandrakesoft.com/show_bug.cgi?id=12561

Theatrics?

Are you kidding?

This problem is plaguing a lot of people's and does not only affect laptops.

There have been no errata's addressing it and it is quite severe.

Yeah it breaks SMP, but the problem is usually not with SMP systems.


Someone really dropped the ball on this one, citing that it was a known problem on cooker is a rather trite response.
 
  


Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
Diff between mdk 10.1 official and mdk 10.1 community Damitha Mandriva 2 12-13-2004 02:01 AM
MDK 10.1 community download Q Nigh Unstoppabl Mandriva 3 09-27-2004 06:42 PM
mandrake 10 community freezes pizuka3400 Mandriva 5 08-04-2004 01:51 PM
Can't boot MDK 10 Community any more mhl Mandriva 3 06-08-2004 02:25 PM
MDK official vs community Sherpa Mandriva 12 06-06-2004 06:11 AM

LinuxQuestions.org > Forums > Linux Forums > Linux - Distributions > Mandriva

All times are GMT -5. The time now is 05:55 PM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration