# [HOWTO] Enable local APIC on DELL INSPIRON/LATITUDE

## mfkr79

Revisions

Initial release --> 5 July 2004

Last Update --> 25 October 2004, added  procedure for 2.6.9 kernels and other considerations in my feedback post

Definition

APIC means Advanced Programmable Interrupt Controller, an improved version of PIC.

It is a Programmable Interrupt Controller that can handle interrupts from and for multiple CPUs, and, usually, has more available interrupt lines that a typical PIC.

APIC must not be confused with ACPI, that stands for Advanced Configuration and Power Interface, and is an open industry standard for configuration and power management.

Why ?

APIC is important not only in multi-processor environment, but could be useful in uniprocessor too, in order to resolve resource conflicts and cause is necessary for enabling new features in the PCI specifications.

I see some people complaining about problems with Linux on their Inspiron, they think these problems could be related to the lack of APIC support in the kernel.

I'm quite happy with the Gentoo installation on my Inspiron 8500, but recently, using lastest kernel versions, I find too many components using the same IRQs (the so called IRQ-sharing).

This behaviour sometime brings to strange outputs in dmesg, something like "can't grab IRQ xx". This force me to disable some options/features in order to mantain my system usable.

So I decide to try enabling local APIC on my DELL, to see if this help to solve this kind of problems.

As my attempt was successful, I decide to share it with Gentoo users, hoping this could solve other problems or help us to understand which Inspiron/Latitude models works well with local APIC enabled, and if is better to leave it disabled or not.

Who can/should try this ?

If you're completly satisfied with your Linux config, don't try this procedure; but if you are extremely mad & curious (like me  :Smile: ) or think local APIC could improve your system config or help solving some kind of problems, continue this reading.

I don't know if ALL  Inspiron/Latitude really have problems with handling enabled local APICs.

To my knowledge, kernel devs have blacklisted them because early models have problems.

Googling around I can't find any evidence of the fact that all recent Inspiron (like mine) can't handle correctly APIC, and it seems that someone else has tried to enable it.

Bottom line:

all users with Pentium4, mobile Pentium4 and mobile Pentium4-M can try, cause the Pentium4 processor family has local APIC, my Inspiron is working.

Pentium-M (Centrino) seems to work with local APIC enabled.

Pentium3-based models probably are the cause of the blacklisting of early Inspiron/Latitude.

They have a BIOS bug that can't be worked around, except by refusing to enable the local APIC  :Sad: 

In particular 

Inspiron 8600 : has Pentium-M, seems to work with APIC

Inspiron 8500 : has mobile Pentium4-M, mine works well with local APIC enabled

Inspiron 8200 : has mobile Pentium4-M, probably has problems with APIC

Inspiron 51x0 : some have Pentium4, other mobile Pentium4, the early models haven't HyperThreading, on a 5150 equipped with mobile Pentium4 (NO HT) one user reports responsiveness improvements and better IRQ management with local APIC enabled

Inspiron xx0m : I believe all have Pentium-M, waiting for feedback...

To my knowledge the commercial brand "Latitude" is targeted to business clients and has the same components of the correspondent Inspiron models, so see above

Latitude D600 : has Pentium-M, works

Latitude C640 : has mobile Pentium4-M, probably has problems with the local APIC enabled

Latitude X200 : has Pentium3, seems fine

Requirements

2.6 kernel tree

DELL notebook with this message in dmesg

```
Dell Inspiron with broken BIOS detected. Refusing to enable the local APIC.
```

or this one

```
Dell Latitude with broken BIOS detected. Refusing to enable the local APIC.
```

Obviously you won't see this message if you don't select in your kernel config

```
Processor type and features  --->  [*] Local APIC support on uniprocessors
```

---EDIT---

Starting from 2.6.9 kernels the Inspiron/Latitude series is no more blacklisted,

so you won't see the above message if you enable APIC in your config

and conseguently the following part "Instructions" is no more needed  :Razz: 

You only have to do  these simple things:

Enable both Local & IO APIC

```
Processor type and features  --->

[*] Local APIC support on uniprocessors

[*]   IO-APIC support on uniprocessors
```

compile kernel and reboot the machine

If this is not sufficient, you will see something like this in dmesg

```
...

No local APIC, or hardware disabled
```

Then you need a further step, ie you have to pass to your bootloader these parameters

```
apic=debug lapic
```

and reboot

Now you should see something like this in dmesg

```
Local APIC disabled by BIOS -- reenabling.

Found and enabled local APIC!

mapped APIC to ffffd000 (fee00000)

...

```

---/EDIT---

Instructions

[ I will leave this part, even if is no more needed with 2.6.9 kernels, for those who want to play with older kernels  :Cool:  ]

Now we are going to force the use of local APIC

  Identify the directory containing the kernel source, usually something like /usr/src/"your kernel"

 Move to the directory /usr/src/"your kernel"/arch/i386/kernel

 With your favourite text editor, open the file named dmi_scan.c

 Find the rows corresponding to your notebook model and comment out them using /* */ ...in this way:

/*

the part of code you have to disable

*/

For Inspiron:

```
{ local_apic_kills_bios, "Dell Inspiron", {

         MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),

         MATCH(DMI_PRODUCT_NAME, "Inspiron"),

         NO_MATCH, NO_MATCH

         } },

```

For Latitude:

```
{ local_apic_kills_bios, "Dell Latitude", {

         MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),

         MATCH(DMI_PRODUCT_NAME, "Latitude"),

         NO_MATCH, NO_MATCH

         } },

```

 Save the file dmi_scan.c and compile the modified kernel source. Don't forget you have to select (NOT as modules)

```
Processor type and features  --->

[*] Local APIC support on uniprocessors

[*]   IO-APIC support on uniprocessors

<*> /dev/cpu/microcode - Intel IA32 CPU microcode support

<*> /dev/cpu/*/msr - Model-specific register support

<*> /dev/cpu/*/cpuid - CPU information support

```

 Reboot selecting the recompiled kernel and check dmesg output

If you find a message like this "No local APIC, or hardware disabled" jump to next step;

if the local APIC is enabled, the procedure ends here, if you want, go to (12)

Is necessary another change to the kernel source.

Move to /usr/src/"nome kernel"/arch/i386/kernel

 With your favourite text editor, open the file named apic.c

 Find the part of source showed here...

```
goto no_apic;

case X86_VENDOR_INTEL:

   if (boot_cpu_data.x86 == 6 ||

      (boot_cpu_data.x86 == 15 && (cpu_has_apic ||enable_local_apic > 0)) ||     

      (boot_cpu_data.x86 == 5 && cpu_has_apic))

         break;

   goto no_apic;

default:

   goto no_apic;

}

```

...comment out this line with /* code */

```
(boot_cpu_data.x86 == 15 && (cpu_has_apic || enable_local_apic > 0)) ||

```

...and change it with this one

```
(boot_cpu_data.x86 == 15 || enable_local_apic > 0) ||

```

 Save the file apic.c and compile the modified kernel source. Don't forget you have to select (NOT as modules)

```
Processor type and features  --->

[*] Local APIC support on uniprocessors

[*]   IO-APIC support on uniprocessors

<*> /dev/cpu/microcode - Intel IA32 CPU microcode support

<*> /dev/cpu/*/msr - Model-specific register support

<*> /dev/cpu/*/cpuid - CPU information support

```

 Reboot selecting the recompiled kernel and check dmesg output

You should read this

```
Local APIC disabled by BIOS -- reenabling.

Found and enabled local APIC!

 ...

Using local APIC timer interrupts.

calibrating APIC timer ...

..... CPU clock speed is xxxx MHz.

..... host bus clock speed is xxx MHz.

```

 Now "apic" is one of the CPU flags, to check this, write

```
cat /proc/cpuinfo | grep flags
```

I obtain

```
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe cid
```

I'm glad to receive comments and critics too, in particular I'd like some feedback where you say if it works, your laptop model, Cpu type, BIOS version, kernel used, ACPI subsys revision and so on...

Disclaimer: Remember please that these are low level stuffs, I'm not responsible if you damage your config, your data or your laptop following this procedure.

I'm not a kernel developer, nor a coder, these modifications work for me, I don't think they're dangerous, but I can't promise they'll work for you too

Bye

This is the translation of the original italian version

Questa è la traduzione della versione originale in italianoLast edited by mfkr79 on Mon Oct 25, 2004 10:00 pm; edited 19 times in total

----------

## mfkr79

Meanwhile,

this is my own feedback  :Cool: 

Local APIC works well on DELL Inspiron 8500 with BIOS A06

CPU type = mobile Intel Pentium4-M 2.4 GHz (cpu family 15, model 2, stepping 7)

Till now I've tried these kernels :

linux-2.6.7-gentoo-r8 (ACPI Subsystem revision 20040326)

linux-2.6.7-love5 (ACPI Subsystem revision 20040615)

linux-2.6.8-rc2-love3 (ACPI Subsystem revision 20040326)

linux-2.6.9-gentoo-r1 (ACPI Subsystem revision 20040816)

No lockups at all, system seems rock solid, all services work as usual... I've played with some games (UT2003/04, RtCW, Doom3), ripped CD & DVD, browsing the web and write this howto without apparent problems   :Wink: 

I don't have immediate death on power unplug, tried several times

No performance enhancements at all.

System responsiveness seems the same...

Only a major annoyance, the shutdown sequence is completed correctly (all services stopped and all partitions unmounted), but at the end the system displays "power down" without turning off, so I have to hold down the power button for 5 secs (this doesn't happen without APIC)

IMHO, on Inspiron 8500, life is better without APIC, until I won't be able to use IO APIC, if implemented, for IRQ routing instead of common PIC

Bye

----------

## hanzotutu

```

hanzo@scimd: pts/2: 37 files 1.5Mb-> dmesg | less

...

Local APIC disabled by BIOS -- reenabling.

Found and enabled local APIC!

...

```

CPU type P-M 1.4G, Dell D600, kernel mm-sources-2.6.6

----------

## smart

Latitude C640, Pentium 4M 1.8G, 15.2.7 , BIOS A10

kernel 2.6.7

no go

immediate death on power unplug test

the disappointment increases due to noticeably snappier response while the system is running with APIC

this is unbelievably weak in my opinion. this is not an old BIOS or old machine. Dell should definitely improve on its support since such problems with dell laptops are obviously known since generation 3 pentiums. cannot recommend buying a dell under these circumstances, apic IS an important feature.

----------

## mfkr79

@ hanzotutu : Thanks for your feedback

 *smart wrote:*   

> Latitude C640, Pentium 4M 1.8G, 15.2.7 , BIOS A10
> 
> kernel 2.6.7
> 
> no go
> ...

 

To solve this you can try to pass a custom DSDT (Differentiated System Description Table) to the kernel, cause often that in DELL BIOS is buggy 

Look here for more info

 *Quote:*   

> this is unbelievably weak in my opinion. this is not an old BIOS or old machine. Dell should definitely improve on its support since such problems with dell laptops are obviously known since generation 3 pentiums. cannot recommend buying a dell under these circumstances, apic IS an important feature.

 

I agree, shame on you, DELL !!!

----------

## ercxy

Dell lattitude d600 1.6ghz pentium M worked...

I had some lockups before when I autoload  ndiswrapper module.. I will try if enapling APIC fixes this problem..I don't see any particular gain or loss for the time been..

thanks ..

Well it didn't fix ndiswrapper problem.. suggestion , do not delete the code, just comment out that part... So you can easily convert it to original..

commenting :

/*

the part of the code you don't want

*/

----------

## mfkr79

 *ercxy wrote:*   

> Dell lattitude d600 1.6ghz pentium M worked...
> 
> I had some lockups before when I autoload  ndiswrapper module.. I will try if enapling APIC fixes this problem..I don't see any particular gain or loss for the time been..

 

Thanks for your feedback

 *Quote:*   

> ... suggestion , do not delete the code, just comment out that part... So you can easily convert it to original..

 

Yes, It's better, I'll correct

----------

## smart

 *Quote:*   

> 
> 
> To solve this you can try to pass a custom DSDT (Differentiated System Description Table) to the kernel, cause often that in DELL BIOS is buggy (as mine ) 
> 
> 

 

nice info, still a heck to learn  :Smile: 

However, so far i was not lucky with it. I had just warning in the DTDT, fixed that, but it didn't help. Now i'm trying to look deeper into it. One thing i can say alredy.... it's highly windozeish.

----------

## liuspider

INSPIRON 8600 works!

After step 6, it works  :Wink: 

Gcc 3.3.2, kernel 2.6.7-r1

Thanks.

BTW: no noticable performance improvement are observed...

----------

## liuspider

 *mfkr79 wrote:*   

> Only a minor annoyance, the shutdown sequence is completed correctly (all services stopped and all partitions unmounted), but at the end the system displays "power down" without turning off, so I have to hold down the power button for 5 secs (this doesn't happen without APIC)
> 
> 

 

Same problem here, hope I can find a solution...

----------

## mfkr79

 *liuspider wrote:*   

> Same problem here, hope I can find a solution...

 

Thanks for the info, I'm working on it...

----------

## appleboy

great thing you got going there, it worked for me after going through all of the steps (6+)

I'm using :

gentoo-dev-sources 2.6.7-r9

dell inspiron 8500

gcc 3.3.3

I'm also having the problem with it shutting down, when i run 'init 0' it comes to the part where it says 'power down' and then stalls and i have to hold the button, but other then that it works like a charm.

----------

## d-fens

running 2.6.7-gentoo-r3 and gcc-Version 3.3.2 20031218 (Gentoo Linux 3.3.2-r5, propolice-3.3-7) on a inspiron 8200

well, feels pretty much as before, apart from not shutting down like stated above...

whats that exactly for anyway ... ?   :Twisted Evil: 

[edit1]

chr, tried to unplug and - freeeeeeeze ... so trying to fix this dst whatever stuff ...

[edit2]

my dsts wasn't buggy (just warnings) but kinda old ... BIOS UPDATE ...

----------

## mfkr79

@ d-fens : thanks for the feedback, You got mobile P4-M on your 8200, is it true?

something better after BIOS update?

----------

## d-fens

hi,

yes i have the P4m but the bios update (A11) didn't solve anything. still i have only warnings in the DSDT, so no need to fix it.

the freezing / no poweroff is quite annoying, so i think i'll disable it ... any further ideas?

----------

## mfkr79

sorry, no further ideas...

Probably 8200 is correctly blacklisted  in kernel code, It should be a 8200 BIOS related problem, and disabling APIC is a way to workaround... other recent Inspiron models seem to work well with APIC enabled

----------

## SMoo

I have a Latitude CPx H500GT, using kernel 2.6.7 r13, BIOS rev A14.

I did all the steps and I still get a broken BIOS in #dmesg | less

Any ideas?

----------

## mfkr79

Correct me if I'm wrong, I suppose you have a P3 on your Latitude

The broken BIOS message still looks like previous

```
Dell Latitude with broken BIOS detected. Refusing to enable the local APIC
```

or is different after doing all steps, can you past it?

However, I can say that older INSPIRON/LATITUDE, especially those with P3, seem to have problems working with APIC enabled, so, probably, you should better leave it disabled...

----------

## teedog

What's the best way to bring this to the attention of the kernel developers?

----------

## Archangel1

Interestingly enough, I've got a P3 Latitude X200 which seems to do APIC fine.

I'm not sure it's something you take to the kernel developers - more something that should be taken to Dell to get them to fix. Of course, we all know the likelihood of this...

I've been fairly appalled to find out how broken these things are though - the DSDT on  mine wasn't quite right. It didn't exactly take a rocket scientist to fix either, so it doesn't give the best impression of Dell's technical ability.

----------

## teedog

I meant to let the kernel developers know that not all Inspirons and Lattitudes should be blacklisted as people seem to find that newer models work fine.

----------

## Archangel1

Ah sorry, misunderstood. 

I didn't try altering the blacklist until recently - dmesg seems to be okay before and after? Maybe it snuck through somehow - possibly it's got a weird model string or something.

----------

## gnasnis

It works for me.

Latitude c810 Pentium III 866 MHz BIOS A12

kernel ; gentoo-dev-sources-2.6.7-r14

I just did the step 1-6.

Thx for good info...

----------

## mfkr79

Thanks guys for feedback...

As you can see in the initial part of the HowTO, I'm trying to create a little and up to date list of working / not-working models

IMHO, the best way to let the kernel developers know about our "experimentations" is to contact, by email for example,  the apic code mantainer...

I don't know who mantains this part of code, if anyone gets this info and tells me I'll do the dirty job  :Wink: 

BTW, I'm still playing with local APIC on my Inspiron, I think next step should be enabling, if possible, IO-APIC to manage the IRQ instead of PIC, as dmesg shows

```
ACPI: Using PIC for interrupt routing
```

I'll give a look to the code when I'm less busy

Bye

----------

## gnasnis

I posted this works for me but I found a strange thing.

Kernel was compiled, when reboot immediately it worked.

If I turn off my pc, my notebook does not power off.

When booting, machine stops.

Only once working...

Hmm, very starange...

----------

## ercxy

Well there is new bios (A13) for lattitude D600, i am sure there is similar bios for inspirons too. .. I don't know if this new bios overcome the Apic problem but after updating my system, boot posting is much more faster.

----------

## kwenspc

local APIC works on Inspiron 5100

-> BIOS A31

-> gentoo-dev-sources-2.6.8-r3

-> dmi_scan.c and apic.c are customized

nevertheless, IO-APIC must be disabled.

----------

## thj

Hrm, I think theres some problem with Dell i8500 + APIC on the 2.6.9-gentoo-r1 kernel.

When I do:

```
# dmesg | grep Dell

It returns:

"i8k: unable to get SMM Dell signature

```

And yes, the Local APIC is enablet in the kernel.

I read on some page, that I should add apic=debug to my kernel parameter in grub.conf because thats required for kernel 2.6.9 (something about it's disabled by BIOS i think).

So, I did that, and heres the output of dmesg:

```
# dmesg | grep APIC

It returns:

No local APIC present or hardware disabled

mapped APIC to ffffd000 (01649000)

Local APIC not tetected. Using dummy APIC emulation.

```

So, it dosen't work. :)

I think that you should know that I can't do step 4, because theres nothing that says "Dell Inspiron" in dmi_scan.c - so maybe it's therefore it dosen't work, but I don't know. Actually dmi_scan.c only contains "DELL GX240" concerning Dell stuff.

I hope you can help me out here, because I get alot of IRQ errors, so I hope that APIC will help on that

----------

## thj

I think I've got a bit closer to solve the problem, after following your guide step by step again and again, and changed stuff in my kernel, I get this msg when doing "dmesg | grep APIC"

"No local APIC present or hardware disabled"

And yes, I have done step 9.

I think it's strange that theres no "Dell Inspiron" section in the dmi_scan.c file.

Another question, have you guys enabled "Dell Support" in the kernel? afaik. it's only for i8000 right?

Hope you can help, bye.

Sys:

Dell i8500

BIOS A06

----------

## thj

I think I've solved the problem now.

What i did, was applying the patch I've found here: http://lkml.org/lkml/2004/10/24/116 and added the kernel parameters lapic and apic=debug.

Heres the results:

```
# dmesg |grep -i apic

Kernel command line: root=/dev/hda5 vga=792 lapic apic=debug

Local APIC disabled by BIOS -- reenabling.

Found and enabled local APIC!

mapped APIC to ffffd000 (fee00000)

Using local APIC timer interrupts.

calibrating APIC timer ...
```

Afaik, that seems to be good.

But, when I do a dmesg | grep -i acpi, i still get alot of "ACPI: PCI interrupt bla bla bla bla IRQ 11"

And thats not good, right?

So what can I do now, to get rid of thoose IRQ interrupts/errors or what you call it?

----------

## mfkr79

 *thj wrote:*   

> Hrm, I think theres some problem with Dell i8500 + APIC on the 2.6.9-gentoo-r1 kernel.
> 
> When I do:
> 
> ```
> ...

 

SMM error message is not related with APIC enabling, BUT with the i8k module, 

the so called "Inspiron laptop support" in the kernel.

It is due to the fact that the driver was developed before the 8500 existence, so it can't correctly recognise our model; in a way (ie forcing module loading)

we can make it works well

The driver reads bios version, cpu temp, fans & a/c status, all good except the fact that fan rotation is uncorrect & CPU / GPU fans status is inverted

you can check all with "cat /proc/i8k" if you load i8k with

"modprobe i8k force=1 restricted=1"

 *Quote:*   

> ...I think that you should know that I can't do step 4, because theres nothing that says "Dell Inspiron" in dmi_scan.c - so maybe it's therefore it dosen't work, but I don't know. Actually dmi_scan.c only contains "DELL GX240" concerning Dell stuff.

 

I last try to enable apic with 2.6.8 series...

If kernel sources are changed, I'm forced to update the HowTO  :Smile: 

 *Quote:*   

> I think I've solved the problem now
> 
> ...
> 
> But, when I do a dmesg | grep -i acpi, i still get alot of "ACPI: PCI interrupt bla bla bla bla IRQ 11" 
> ...

 

Give me  some time to pair my situation with your progress, hopefully tonight I'll come with something new  :Wink: 

BTW, in the meanwhile, Can you post here or send me by pm your last dmesg output and the result of "cat /proc/interrupts" with and without apic enabled ?

Bye

----------

## mfkr79

Thanks to thj I discover that 

the original procedure is no more necessary with 2.6.9 kernels

cause sources are changed

I've updated the initial post...Now enabling APIC it's simpler

----------

## GrimSage

 *Quote:*   

> 
> 
> Then you need a further step, ie you have to pass to your bootloader these parameters
> 
> ```
> ...

 

I am still new to most of this.  Where exactly do I put this?[/quote]

----------

## mfkr79

put in the config file of your bootloader

lilo.conf if you use lilo, in the append section

...

image=/boot/kernel-2.6.x

 label="Gentoo-2.6"

 append="root=/dev/hdx ... apic=debug lapic ..."

grub.conf if you use grub

...

# For booting Gentoo

title  Gentoo Linux 2004 (gentoo-dev-sources)

root (hd?,?)

kernel /boot/kernel-gentoo root=/dev/hdx ... apic=debug lapic ...

Bye

----------

## xanderhsia

On my Dell Inspiron 8600, adding apic=debug lapic does enable the local apic  exactly as stated in the first post. However, it seems to have the very bad side effect of causing the acpi lid event to hard crash my laptop.  :Sad:   I have to do the "hold down the power button for 4 seconds" dance to get out of the hard lock. For whatever strange reason, doing a Fn+F8 (which on the 8600 is a special key combo that is supposed to switch between CRT and the LCD) also causes a crash.  

Removing the apic option on the boot line makes the lid work again and the Fn+F8 combo press innocuous (generates no scancodes/acpi events whatsoever). Mind you that I had no acpi scripts to respond to events, so the crashing is not a result of the laptop trying to enter some unsupported suspend mode. 

So be warned! I googled a bit, but didn't find anything conclusive. APIC support seems to be intimately tangled with the BIOS which is written by the vendor.  And we all know how "superb" vendor BIOS coding is   :Wink: 

If you know a workaround, please post. I'd love to have apic w/o crashing!

----------

## desertstalker

Thought Id post my findings:  The APIC on my D600 works however I cannot resume from S3 if  have it enabled.  This occurs with kernel 2.6.10-rc1 and 2.6.9.

I guess i will leave it unenabled

----------

## paladin-zero

 *mfkr79 wrote:*   

> 
> 
> The broken BIOS message still looks like previous
> 
> ```
> ...

 

I just saw this, don't know if its already known to this forum:

http://www.bay-wolf.com/flashbios.htm#problems

 *Quote:*   

> Known problems with BIOS Versions
> 
>    1. If you are using Linux on an Inspiron 8000, do not upgrade the BIOS beyond version 17. All of the subsequent BIOS images are flawed. The kernel gives this message - "Dell Inspiron with broken BIOS detected. Refusing to enable the local APIC." 

 

----------

## einstein1981

hi guys, been reading up on it, but unfortunatly my english only gets me so far, I just want the battery monitor running on my 5150, I emerged acpid, and added the battery run level, and the script as satedt in the gentoo guide for this.

now I try to add the gnome battery monitor, and still get a message that says  : "Can't access ACPI events in /var/run/acpid.socket! Make sure the ACPI subsystem is working and the acpid daemon is running."

now here is the output of my dmesg, 

```
[B] -> GSI 17 (level, low) -> IRQ 17

ACPI: PCI interrupt 0000:01:00.0[A] -> GSI 20 (level, low) -> IRQ 20

ACPI: PCI interrupt 0000:02:01.0[A] -> GSI 17 (level, low) -> IRQ 17

ACPI: PCI interrupt 0000:02:04.0[A] -> GSI 16 (level, low) -> IRQ 16

ACPI: PCI interrupt 0000:02:04.1[A] -> GSI 16 (level, low) -> IRQ 16

Machine check exception polling timer started.

audit: initializing netlink socket (disabled)

audit(1102972449.387:0): initialized

.

.

.

.

.

ACPI: AC Adapter [AC] (on-line)

ACPI: Battery Slot [BAT0] (battery present)

ACPI: Lid Switch [LID]

ACPI: Power Button (CM) [PBTN]

ACPI: Sleep Button (CM) [SBTN]

ACPI: Processor [CPU0] (supports C1 C2 C3, 8 throttling states)

ACPI: Thermal Zone [THM] (71 C)

i8042.c: Warning: Keylock active.

serio: i8042 AUX port at 0x60,0x64 irq 12

serio: i8042 KBD port at 0x60,0x64 irq 1

Serial: 8250/16550 driver $Revision: 1.90 $ 8 ports, IRQ sharing disabled

ACPI: PCI interrupt 0000:00:1f.6[B] -> GSI 17 (level, low) -> IRQ 17

mice: PS/2 mouse device common for all mice

input: AT Translated Set 2 keyboard on isa0060/serio0

Synaptics Touchpad, model: 1

 Firmware: 5.9

 Sensor: 37

 new absolute packet format

 Touchpad has extended capability bits

```

thanks

----------

## MonsterMord

Hi guys,

with the new 2.6.10-gentoo-r4:

without lapic option

```

dmesg | grep -i apic

Local APIC disabled by BIOS -- you can enable it with "lapic"

mapped APIC to ffffd000 (01405000)

```

with lapic option

```
dmesg | grep -i apic

Kernel command line: root=/dev/hda7 lapic video=vesafb:mtrr,ywrap splash=verbose,theme:linux

Local APIC disabled by BIOS -- reenabling.

Found and enabled local APIC!

mapped APIC to ffffd000 (fee00000)

```

It seems work fine!

----------

## mfkr79

Does it power off normally or not ?

ie, after the shutdown sequence, you don't have to hold down power button for 5 secs to halt the system

----------

## gnasnis

kernel ; gentoo-sources-2.6.10-r6

baselayout ; 1.11.8-r3

Latitude C810 Pentium III 866MHz

Sometimes, my machine stopped during booting.

If boot step passes, APIC works. It seems no problem except stopping during booting.

P.S. Gentoo-sources-2.6.10-r5 kills my USB-HDD, argh!!!

----------

