regression in 2.6.23-rc8 - power off failed

regression in 2.6.23-rc8 - power off failed

[Wolfgang Erig]

Hi,

the latest kernel does not power off my system.

2.6.22 succeeded
2.6.23-rc8 failed

$ git bisect bad  
Bisecting: 0 revisions left to test after this 
[f216cc3748a3a22c2b99390fddcdafa0583791a2] ACPI: suspend: consolidate handling of Sx states.

Which more info is needed?

Wolfgang

regression in 2.6.23-rc8 - power off failed

[Frans Pop]

Wolfgang Erig wrote:
> the latest kernel does not power off my system.

This is a known regression in rc8. See this mail and thread for details:
http://lkml.org/lkml/2007/9/25/239

The issue has already been fixed in Linus' git tree.
Please try again with that, or apply the patches included in the posts
referenced in the message linked above.

Cheers,
Frans Pop

Re: regression in 2.6.23-rc8 - power off failed

[H. Peter Anvin]

Wolfgang Erig wrote:
> Hi,
> 
> the latest kernel does not power off my system.
> 
> 2.6.22 succeeded
> 2.6.23-rc8 failed
> 
> $ git bisect bad  
> Bisecting: 0 revisions left to test after this 
> [f216cc3748a3a22c2b99390fddcdafa0583791a2] ACPI: suspend: consolidate handling of Sx states.
> 
> $ git bisect good 
> Bisecting: 0 revisions left to test after this 
> [626073132b381684c4983e0d911e9aceb32e2cbc] Assembly header and main routine for new x86 setup code 

OK, so which one is the bad one?

	-hpa

regression in 2.6.23-rc8 - power off failed

[Frans Pop]

My apologies for the two bogus addresses in the "To" of my previous
message. Script error, won't happen again.

Frans Pop

Re: regression in 2.6.23-rc8 - power off failed

[Alexey Starikovskiy]

Hi,
This is known issue.
Please try latest rc8-git2, it should contain the fix.

Regards,
Alex.

Wolfgang Erig wrote:
> Hi,
> 
> the latest kernel does not power off my system.
> 
> 2.6.22 succeeded
> 2.6.23-rc8 failed
> 
> $ git bisect bad  
> Bisecting: 0 revisions left to test after this 
> [f216cc3748a3a22c2b99390fddcdafa0583791a2] ACPI: suspend: consolidate handling of Sx states.
> 
> Which more info is needed?
> 
> Wolfgang

Re: regression in 2.6.23-rc8 - power off failed

[Wolfgang Erig]

Both are bad.
Two different systems and two different bisections.
I sent the last step of each.

On Fri, Sep 28, 2007 at 08:05:15PM -0700, H. Peter Anvin wrote:
> Wolfgang Erig wrote:
> > Hi,
> > 
> > the latest kernel does not power off my system.
> > 
> > 2.6.22 succeeded
> > 2.6.23-rc8 failed
> > 
> > $ git bisect bad  
> > Bisecting: 0 revisions left to test after this 
> > [f216cc3748a3a22c2b99390fddcdafa0583791a2] ACPI: suspend: consolidate handling of Sx states.

This is fixed for me after pulling from
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
Thankyou and sorry for the noise.

> > 
> > $ git bisect good 
> > Bisecting: 0 revisions left to test after this 
> > [626073132b381684c4983e0d911e9aceb32e2cbc] Assembly header and main routine for new x86 setup code 
> 
> OK, so which one is the bad one?

This problem (no power off) persists after pull some minutes ago.
Sorry for the confusion.

Wolfgang

Re: regression in 2.6.23-rc8 - power off failed

[H. Peter Anvin]

Wolfgang Erig wrote:
> Both are bad.
> Two different systems and two different bisections.
> I sent the last step of each.

>>> $ git bisect good 
>>> Bisecting: 0 revisions left to test after this 
>>> [626073132b381684c4983e0d911e9aceb32e2cbc] Assembly header and main routine for new x86 setup code 
>> OK, so which one is the bad one?
> 
> This problem (no power off) persists after pull some minutes ago.
> Sorry for the confusion.
> 

I believe there must have been something wrong here (possibly
inconsistent experiments?)  This checkin has *zero code changes* from
the previous one (and next one) -- the kernel should have been binarily
identical to the previous one.  The code introduced in this checkin
doesn't even get compiled until two checkins later,
4fd06960f120e02e9abc802a09f9511c400042a5.

	-hpa

Re: regression in 2.6.23-rc8 - power off failed

[Wolfgang Erig]

On Sat, Sep 29, 2007 at 01:30:33AM -0700, H. Peter Anvin wrote:
> Wolfgang Erig wrote:
> > Both are bad.
> > Two different systems and two different bisections.
> > I sent the last step of each.
> 
> >>> $ git bisect good 
> >>> Bisecting: 0 revisions left to test after this 
> >>> [626073132b381684c4983e0d911e9aceb32e2cbc] Assembly header and main routine for new x86 setup code 
> >> OK, so which one is the bad one?
> > 
> > This problem (no power off) persists after pull some minutes ago.
> > Sorry for the confusion.
> > 
> 
> I believe there must have been something wrong here (possibly
> inconsistent experiments?)  This checkin has *zero code changes* from
> the previous one (and next one) -- the kernel should have been binarily
> identical to the previous one.  The code introduced in this checkin
> doesn't even get compiled until two checkins later,
> 4fd06960f120e02e9abc802a09f9511c400042a5.

I have done two bisections simultanously and it was late at night.
I start again with a fresh tree and better controlled experiments.

Wolfgang

Re: regression in 2.6.23-rc8 - power off failed

[Mark Lord]

Wolfgang Erig wrote:
> On Sat, Sep 29, 2007 at 01:30:33AM -0700, H. Peter Anvin wrote:
>> Wolfgang Erig wrote:
>>> Both are bad.
>>> Two different systems and two different bisections.
>>> I sent the last step of each.
>>>>> $ git bisect good 
>>>>> Bisecting: 0 revisions left to test after this 
>>>>> [626073132b381684c4983e0d911e9aceb32e2cbc] Assembly header and main routine for new x86 setup code 
>>>> OK, so which one is the bad one?
>>> This problem (no power off) persists after pull some minutes ago.
>>> Sorry for the confusion.
>>>
>> I believe there must have been something wrong here (possibly
>> inconsistent experiments?)  This checkin has *zero code changes* from
>> the previous one (and next one) -- the kernel should have been binarily
>> identical to the previous one.  The code introduced in this checkin
>> doesn't even get compiled until two checkins later,
>> 4fd06960f120e02e9abc802a09f9511c400042a5.
> 
> I have done two bisections simultanously and it was late at night.
> I start again with a fresh tree and better controlled experiments.

If this is an SMP system, then you could just be getting random results,
depending upon which CPU is attempting the poweroff.

I have a newish patch in Andrew's tree now to fix SMP poweroff
(has been broken forever), reproduced here below in case you missed it.

* * *
We need to disable all CPUs other than the boot CPU (usually 0)
before attempting to power-off modern SMP machines.
This fixes the hang-on-poweroff issue on my MythTV SMP box,
and also on Thomas Gleixner's new toybox.

Signed-off-by: Mark Lord <mlord@pobox.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
---

--- linux/kernel/sys.c.orig	2007-09-13 09:49:11.000000000 -0400
+++ linux/kernel/sys.c	2007-09-28 15:48:54.000000000 -0400
@@ -32,6 +32,7 @@
 #include <linux/getcpu.h>
 #include <linux/task_io_accounting_ops.h>
 #include <linux/seccomp.h>
+#include <linux/cpu.h>
 
 #include <linux/compat.h>
 #include <linux/syscalls.h>
@@ -878,6 +879,7 @@
 	kernel_shutdown_prepare(SYSTEM_POWER_OFF);
 	if (pm_power_off_prepare)
 		pm_power_off_prepare();
+	disable_nonboot_cpus();
 	sysdev_shutdown();
 	printk(KERN_EMERG "Power down.\n");
 	machine_power_off();

Re: regression in 2.6.23-rc8 - power off failed

[Alexey Starikovskiy]

Mark Lord wrote:
> Wolfgang Erig wrote:
>> On Sat, Sep 29, 2007 at 01:30:33AM -0700, H. Peter Anvin wrote:
>>> Wolfgang Erig wrote:
>>>> Both are bad.
>>>> Two different systems and two different bisections.
>>>> I sent the last step of each.
>>>>>> $ git bisect good Bisecting: 0 revisions left to test after this 
>>>>>> [626073132b381684c4983e0d911e9aceb32e2cbc] Assembly header and 
>>>>>> main routine for new x86 setup code 
>>>>> OK, so which one is the bad one?
>>>> This problem (no power off) persists after pull some minutes ago.
>>>> Sorry for the confusion.
>>>>
>>> I believe there must have been something wrong here (possibly
>>> inconsistent experiments?)  This checkin has *zero code changes* from
>>> the previous one (and next one) -- the kernel should have been binarily
>>> identical to the previous one.  The code introduced in this checkin
>>> doesn't even get compiled until two checkins later,
>>> 4fd06960f120e02e9abc802a09f9511c400042a5.
>>
>> I have done two bisections simultanously and it was late at night.
>> I start again with a fresh tree and better controlled experiments.
> 
> If this is an SMP system, then you could just be getting random results,
> depending upon which CPU is attempting the poweroff.
> 
> I have a newish patch in Andrew's tree now to fix SMP poweroff
> (has been broken forever), reproduced here below in case you missed it.
> 
> * * *
> We need to disable all CPUs other than the boot CPU (usually 0)
> before attempting to power-off modern SMP machines.
> This fixes the hang-on-poweroff issue on my MythTV SMP box,
> and also on Thomas Gleixner's new toybox.
> 
> Signed-off-by: Mark Lord <mlord@pobox.com>
> Acked-by: Thomas Gleixner <tglx@linutronix.de>
> ---
> 
> --- linux/kernel/sys.c.orig    2007-09-13 09:49:11.000000000 -0400
> +++ linux/kernel/sys.c    2007-09-28 15:48:54.000000000 -0400
> @@ -32,6 +32,7 @@
> #include <linux/getcpu.h>
> #include <linux/task_io_accounting_ops.h>
> #include <linux/seccomp.h>
> +#include <linux/cpu.h>
> 
> #include <linux/compat.h>
> #include <linux/syscalls.h>
> @@ -878,6 +879,7 @@
>     kernel_shutdown_prepare(SYSTEM_POWER_OFF);
>     if (pm_power_off_prepare)
>         pm_power_off_prepare();
> +    disable_nonboot_cpus();
>     sysdev_shutdown();
>     printk(KERN_EMERG "Power down.\n");
>     machine_power_off();

-static void
-acpi_power_off (void)
-{
-       printk("%s called\n",__FUNCTION__);
-       /* Some SMP machines only can poweroff in boot CPU */
-       set_cpus_allowed(current, cpumask_of_cpu(0));
ACPI in kernel 2.6.12 did disable non-boot cpus too in powe_off.
Later only comment was left for some reason...
Regards,
Alex. 

Re: regression in 2.6.23-rc8 - power off failed

[Wolfgang Erig]

Hi Peter,

On Sat, Sep 29, 2007 at 11:35:53AM +0200, Wolfgang Erig wrote:
>
> I start again with a fresh tree and better controlled experiments.

now the result of bisection seems to be consistent.

The last good commit is
f2d98ae63dc64dedb00499289e13a50677f771f9 Linker script for the new x86 setup code

The first bad commit (no power off) is
4fd06960f120e02e9abc802a09f9511c400042a5 Use the new x86 setup code for i386

Now I try the things written in
http://marc.info/?i=46FD802D.2030804@zytor.com

Wolfgang

Re: regression in 2.6.23-rc8 - power off failed

[Wolfgang Erig]

Hi Peter,

On Sat, Sep 29, 2007 at 08:07:21PM +0200, Wolfgang Erig wrote:
> 
> Now I try the things written in
> http://marc.info/?i=46FD802D.2030804@zytor.com

I have dumped a memory region which is my understanding what you want
to see. The difference between the good and the bad case is only
the patch
"4fd06960f120e02e9abc802a09f9511c400042a5 Use the new x86 setup code for i386"

I modified arch/i386/kernel/setup.c and dumped 4K of /dev/kmem at the
address of boot_params.

Good case:
c0457340 > 00 08 fc ff 00 00 03 50  8c c8 03 00 8e c0 19 01 < .......P........
c0457350 > 10 00 7c fb fc be 31 00  ac 20 c0 74 09 b4 0e bb < ..|...1.. .t....
c0457360 > 07 00 cd 10 eb f2 31 c0  cd 16 cd 19 ea f0 ff 00 < ......1.........
c0457370 > f0                                               < .
c0457371  "Direct booting "
c0457380 > 02 01 00 f0 ff 96 00 00  00 f0 40 00 03 00 ff ff < ..........@.....
c0457390 > ff ff ff ff                                      < ....
c0457394  "nger supported."
c04573a3 > 0d 0a                                            < ..
c04573a5  "Please use a boot loader prp4"
c04573c2 > 0f 00 00 00 00 00 08 00  00 00 70 34 3f          < ..........p4?
c04573cf    11 * 00
c04573e0 > 08 00 fc 01 00 74 00 00  00 00                   < .....t....
c04573ea  " key to reboot . . ."
c04573fe > 0d 0a                                            < ..
c0457400   121 * 00
c0457521 > fc 01 00 00 00 09 00 05  00 00 00 00 00 00 00 00 < ................
c0457531 > 0e 01 00 f4 a4 01 00 00  00 00 0f 02 08 55 aa eb < .............U..
c0457541  ":HdrS"
c0457546 > 06 02 00 00 00 00 00 10  7f 11 71 81 00 80 00 00 < ..........q.....
c0457556 > 10 00 00 00 00 00 00 00  00 00 00 00 00 00 00 8e < ................
c0457566 > 00 00 00 90 09 00 ff ff  ff 1f 00 00 10 00 00 00 < ................
c0457576 > 00 00 ff 07 00 00 e8 c1  0c 90                   < ..........
c0457580    99 * 00
c0457619 > fc 09 00 00 00 00 00 01  00 00 00 00 fc 09 00 00 < ................
c0457629 > 00 00 00 00 04 00 00 00  00 00 00 02 00 00 00 3a < ...............:
c0457639 > 12 0f 00 00 00 00 00 c6  ed 00 00 00 00 00 00 02 < ................
c0457649 > 00 00 00 00 00 10 00 00  00 00 00 00 00 f0 07 00 < ................
c0457659 > 00 00 00 01 00 00 00 3a  12 ff ff 00 00 00 00 c6 < .......:........
c0457669 > ed 00 00 00 00 00 00 02                          < ........
c0457671   bcf * 00
c0458240 > b8 00 15 b2 81 cd 13 8c  c8 8e d8 81 3e a5 1b 55 < ............>..U
c0458250 > aa 75 4c 81 3e a7 1b                             < .uL.>..
c0458257  "ZZuD"
c045825b > eb 40 ac 20 c0 74 05 e8  08 00 eb f6 c3 e8 00 00 < .@. .t..........
c045826b > b0 20 50 51 bb 07 00 b9  01 00 b4 0e cd 10 59 58 < . PQ..........YX
c045827b > c3 b0 07 eb ed                                   < .....
c0458280  "No setup signature found ..."
c045829c > 00 eb 4f 8c c8 83 e8 20  8e d8 30 ff 8a 1e f1 01 < ..O.... ..0.....
c04582ac > 83 eb 04 c1 e3 08 89 d9  c1 eb 03 81 c3 00 10 2e < ................
c04582bc > 89 1e 0c 00 bf 00 08 29  f6 0e 07 b8 00 10 8e d8 < .......)........
c04582cc > f3 a5 8c c8 8e d8 81 3e  a5 1b 55 aa 75 0a 81 3e < .......>..U.u..>
c04582dc > a7 1b 5a 5a 75 02 eb 0a  8d 36 40 0d e8 72 ff f4 < ..ZZu....6@..r..
c04582ec > eb fd 8c c8 83 e8 20 8e  d8 2e f6 06 11 00 01 74 < ...... ........t
c04582fc > 2e 2e 80 3e 10 00 00 75  26 0e 1f 8d 36 d0 0d e8 < ...>...u&...6...
c045830c > 4f ff eb db                                      < O...
c0458310  "Wrong loader, giving up..."
c045832a > 00 e8 36 00 66 85 c0 74  61 8c c8 8e d8 8d 36 00 < ..6.f..ta.....6.
c045833a > 0e e8 1f ff eb fe                                < ......

Bad case:
c0457340 > 00 08 00 00 00 00 03 50  00 00 03 00 00 00 19 01 < .......P........
c0457350 > 10                                               < .
c0457351    4f * 00
c04573a0 > 80 86 00 00 00 00 00 00  00 00 00 00             < ............
c04573ac  "CISG"
c04573b0    30 * 00
c04573e0 > 08 00 fc 01 00 74                                < .....t
c04573e6   13e * 00
c0457524 > e0 29 09 00 05 00 00 00  00 00 00 00 00 13 01 00 < .)..............
c0457534 > fa a4 01 00 00 00 ff ff  02 08 55 aa eb          < ..........U..
c0457541  ":HdrS"
c0457546 > 06 02 00 00 00 00 00 10  3c 23 71 81 00 80 00 00 < ........<#q.....
c0457556 > 10 00 00 00 00 00 00 00  00 00 00 00 00 00 00 8e < ................
c0457566 > 00 00 00 90 09 00 ff ff  ff 1f 00 00 10          < .............
c0457573    a6 * 00
c0457619 > fc 09 00 00 00 00 00 01  00 00 00 00 fc 09 00 00 < ................
c0457629 > 00 00 00 00 04 00 00 00  00 00 00 02 00 00 00 3a < ...............:
c0457639 > 12 0f 00 00 00 00 00 c6  ed 00 00 00 00 00 00 02 < ................
c0457649 > 00 00 00 00 00 10 00 00  00 00 00 00 00 f0 07 00 < ................
c0457659 > 00 00 00 01 00 00 00 3a  12 ff ff 00 00 00 00 c6 < .......:........
c0457669 > ed 00 00 00 00 00 00 02                          < ........
c0457671   ccf * 00

$ cat /proc/cmdline
root=/dev/hda1

Wolfgang

Re: regression in 2.6.23-rc8 - power off failed

[Bill Davidsen]

Alexey Starikovskiy wrote:

> -static void
> -acpi_power_off (void)
> -{
> -       printk("%s called\n",__FUNCTION__);
> -       /* Some SMP machines only can poweroff in boot CPU */
> -       set_cpus_allowed(current, cpumask_of_cpu(0));
> ACPI in kernel 2.6.12 did disable non-boot cpus too in powe_off.
> Later only comment was left for some reason...
> 
Am I midreading that code, or does it really assume that the boot cpu is 
always zero? Or just that zero will be able to do the power off?

In any case I have had an SMP machine which did not have a CPU zero, and 
it was discussed here, I believe. Wonder what happens if you set 
affinity to a CPU you don't have...

-- 
Bill Davidsen <davidsen@tmr.com>
   "We have more to fear from the bungling of the incompetent than from
the machinations of the wicked."  - from Slashdot

Re: regression in 2.6.23-rc8 - power off failed

[Rafael J. Wysocki]

On Saturday, 29 September 2007 22:47, Bill Davidsen wrote:
> Alexey Starikovskiy wrote:
> 
> > -static void
> > -acpi_power_off (void)
> > -{
> > -       printk("%s called\n",__FUNCTION__);
> > -       /* Some SMP machines only can poweroff in boot CPU */
> > -       set_cpus_allowed(current, cpumask_of_cpu(0));
> > ACPI in kernel 2.6.12 did disable non-boot cpus too in powe_off.
> > Later only comment was left for some reason...
> > 
> Am I midreading that code, or does it really assume that the boot cpu is 
> always zero? Or just that zero will be able to do the power off?
> 
> In any case I have had an SMP machine which did not have a CPU zero, and 
> it was discussed here, I believe. Wonder what happens if you set 
> affinity to a CPU you don't have...

Good question, but it also caused other problems to appear, IIRC.

IMHO, it's better to call disable_nonboot_cpus() in an appropriate place
anyway.

Greetings,
Rafael

Re: regression in 2.6.23-rc8 - power off failed

[H. Peter Anvin]

Wolfgang Erig wrote:
> Hi Peter,
> 
> On Sat, Sep 29, 2007 at 11:35:53AM +0200, Wolfgang Erig wrote:
>> I start again with a fresh tree and better controlled experiments.
> 
> now the result of bisection seems to be consistent.
> 
> The last good commit is
> f2d98ae63dc64dedb00499289e13a50677f771f9 Linker script for the new x86 setup code
> 
> The first bad commit (no power off) is
> 4fd06960f120e02e9abc802a09f9511c400042a5 Use the new x86 setup code for i386
> 
> Now I try the things written in
> http://marc.info/?i=46FD802D.2030804@zytor.com
> 

OK, that makes more sense.  I'll look at this on Monday.

	-hpa

Re: regression in 2.6.23-rc8 - power off failed

[Alexey Starikovskiy]

Rafael J. Wysocki wrote:
> On Saturday, 29 September 2007 22:47, Bill Davidsen wrote:
>> Alexey Starikovskiy wrote:
>>
>>> -static void
>>> -acpi_power_off (void)
>>> -{
>>> -       printk("%s called\n",__FUNCTION__);
>>> -       /* Some SMP machines only can poweroff in boot CPU */
>>> -       set_cpus_allowed(current, cpumask_of_cpu(0));
>>> ACPI in kernel 2.6.12 did disable non-boot cpus too in powe_off.
>>> Later only comment was left for some reason...
>>>
>> Am I midreading that code, or does it really assume that the boot cpu is 
>> always zero? Or just that zero will be able to do the power off?
>>
>> In any case I have had an SMP machine which did not have a CPU zero, and 
>> it was discussed here, I believe. Wonder what happens if you set 
>> affinity to a CPU you don't have...
> 
> Good question, but it also caused other problems to appear, IIRC.
> 
> IMHO, it's better to call disable_nonboot_cpus() in an appropriate place
> anyway.
> 
> Greetings,
> Rafael
Ok, here is commit which removed the code in question from acpi_power_off:

commit 6660316cb7a1a2c59a73a52870490c0f782f45c1
Author: Eric W. Biederman <ebiederm@xmission.com>
Date:   Tue Jul 26 12:16:00 2005 -0600

    [PATCH] acpi_power_off: Don't switch to the boot cpu

    machine_power_off on i386 and x86_64 now switch to the
    boot cpu out of paranoia and because the MP Specification indicates it
    is a good idea on reboot, so for those architectures it is a noop.
    I can't see anything in the acpi spec that requires you to be on
    the boot cpu to power off the system, so this should not be an issue
    for ia64.  In addition ia64 has the altix a massive multi-node
    system where switching to the boot cpu sounds insane as we may
    hot removed the boot cpu.

    Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
    Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Regards,
Alex.

Re: regression in 2.6.23-rc8 - power off failed

[Rafael J. Wysocki]

On Monday, 1 October 2007 19:55, Alexey Starikovskiy wrote:
> Rafael J. Wysocki wrote:
> > On Saturday, 29 September 2007 22:47, Bill Davidsen wrote:
> >> Alexey Starikovskiy wrote:
> >>
> >>> -static void
> >>> -acpi_power_off (void)
> >>> -{
> >>> -       printk("%s called\n",__FUNCTION__);
> >>> -       /* Some SMP machines only can poweroff in boot CPU */
> >>> -       set_cpus_allowed(current, cpumask_of_cpu(0));
> >>> ACPI in kernel 2.6.12 did disable non-boot cpus too in powe_off.
> >>> Later only comment was left for some reason...
> >>>
> >> Am I midreading that code, or does it really assume that the boot cpu is 
> >> always zero? Or just that zero will be able to do the power off?
> >>
> >> In any case I have had an SMP machine which did not have a CPU zero, and 
> >> it was discussed here, I believe. Wonder what happens if you set 
> >> affinity to a CPU you don't have...
> > 
> > Good question, but it also caused other problems to appear, IIRC.
> > 
> > IMHO, it's better to call disable_nonboot_cpus() in an appropriate place
> > anyway.
> > 
> > Greetings,
> > Rafael
> Ok, here is commit which removed the code in question from acpi_power_off:
> 
> commit 6660316cb7a1a2c59a73a52870490c0f782f45c1
> Author: Eric W. Biederman <ebiederm@xmission.com>
> Date:   Tue Jul 26 12:16:00 2005 -0600
> 
>     [PATCH] acpi_power_off: Don't switch to the boot cpu
> 
>     machine_power_off on i386 and x86_64 now switch to the
>     boot cpu out of paranoia and because the MP Specification indicates it
>     is a good idea on reboot, so for those architectures it is a noop.
>     I can't see anything in the acpi spec that requires you to be on
>     the boot cpu to power off the system, so this should not be an issue
>     for ia64.  In addition ia64 has the altix a massive multi-node
>     system where switching to the boot cpu sounds insane as we may
>     hot removed the boot cpu.
> 
>     Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
>     Signed-off-by: Linus Torvalds <torvalds@osdl.org>

I see. :-)

Anyway, I think we should atually go UP before executing sysdev_shutdown().

How we are going to do that is another matter.

Greetings,
Rafael

Re: regression in 2.6.23-rc8 - power off failed: solved

[Wolfgang Erig]

On Mon, Oct 08, 2007 at 11:48:40AM -0700, H. Peter Anvin wrote:
>
> Does your .config file have CONFIG_APM=y?  Otherwise, that's your problem 
> right there (since your old laptop doesn't appear to have ACPI.)

no CONFIG_APM and yes, this is my problem.
A very hard way to figure this out,
and too much noise. Sorry for this.

It is not the first time, I had to change my .config to maintain a
feature of the kernel after an upgrade. I think, you are aware of this
an I have no suggestion for improvement. Now this old laptop is
running perfectly again with the latest kernel.

Thankyou for this,
Wolfgang