<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/arch/x86/kernel/reboot.c, branch v4.4.45</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>x86/reboot/quirks: Add iMac10,1 to pci_reboot_dmi_table[]</title>
<updated>2016-01-31T19:28:54+00:00</updated>
<author>
<name>Mario Kleiner</name>
<email>mario.kleiner.de@gmail.com</email>
</author>
<published>2015-12-18T19:24:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8d9b56970b10369a7fe09e8d95096c6e33fe5b78'/>
<id>8d9b56970b10369a7fe09e8d95096c6e33fe5b78</id>
<content type='text'>
commit 2f0c0b2d96b1205efb14347009748d786c2d9ba5 upstream.

Without the reboot=pci method, the iMac 10,1 simply
hangs after printing "Restarting system" at the point
when it should reboot. This fixes it.

Signed-off-by: Mario Kleiner &lt;mario.kleiner.de@gmail.com&gt;
Cc: Andy Lutomirski &lt;luto@amacapital.net&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Brian Gerst &lt;brgerst@gmail.com&gt;
Cc: Dave Jones &lt;davej@codemonkey.org.uk&gt;
Cc: Denys Vlasenko &lt;dvlasenk@redhat.com&gt;
Cc: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: http://lkml.kernel.org/r/1450466646-26663-1-git-send-email-mario.kleiner.de@gmail.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 2f0c0b2d96b1205efb14347009748d786c2d9ba5 upstream.

Without the reboot=pci method, the iMac 10,1 simply
hangs after printing "Restarting system" at the point
when it should reboot. This fixes it.

Signed-off-by: Mario Kleiner &lt;mario.kleiner.de@gmail.com&gt;
Cc: Andy Lutomirski &lt;luto@amacapital.net&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Brian Gerst &lt;brgerst@gmail.com&gt;
Cc: Dave Jones &lt;davej@codemonkey.org.uk&gt;
Cc: Denys Vlasenko &lt;dvlasenk@redhat.com&gt;
Cc: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: http://lkml.kernel.org/r/1450466646-26663-1-git-send-email-mario.kleiner.de@gmail.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>kexec: split kexec_load syscall from kexec core code</title>
<updated>2015-09-10T20:29:01+00:00</updated>
<author>
<name>Dave Young</name>
<email>dyoung@redhat.com</email>
</author>
<published>2015-09-09T22:38:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=2965faa5e03d1e71e9ff9aa143fff39e0a77543a'/>
<id>2965faa5e03d1e71e9ff9aa143fff39e0a77543a</id>
<content type='text'>
There are two kexec load syscalls, kexec_load another and kexec_file_load.
 kexec_file_load has been splited as kernel/kexec_file.c.  In this patch I
split kexec_load syscall code to kernel/kexec.c.

And add a new kconfig option KEXEC_CORE, so we can disable kexec_load and
use kexec_file_load only, or vice verse.

The original requirement is from Ted Ts'o, he want kexec kernel signature
being checked with CONFIG_KEXEC_VERIFY_SIG enabled.  But kexec-tools use
kexec_load syscall can bypass the checking.

Vivek Goyal proposed to create a common kconfig option so user can compile
in only one syscall for loading kexec kernel.  KEXEC/KEXEC_FILE selects
KEXEC_CORE so that old config files still work.

Because there's general code need CONFIG_KEXEC_CORE, so I updated all the
architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects
KEXEC_CORE in arch Kconfig.  Also updated general kernel code with to
kexec_load syscall.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Dave Young &lt;dyoung@redhat.com&gt;
Cc: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Cc: Vivek Goyal &lt;vgoyal@redhat.com&gt;
Cc: Petr Tesarik &lt;ptesarik@suse.cz&gt;
Cc: Theodore Ts'o &lt;tytso@mit.edu&gt;
Cc: Josh Boyer &lt;jwboyer@fedoraproject.org&gt;
Cc: David Howells &lt;dhowells@redhat.com&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There are two kexec load syscalls, kexec_load another and kexec_file_load.
 kexec_file_load has been splited as kernel/kexec_file.c.  In this patch I
split kexec_load syscall code to kernel/kexec.c.

And add a new kconfig option KEXEC_CORE, so we can disable kexec_load and
use kexec_file_load only, or vice verse.

The original requirement is from Ted Ts'o, he want kexec kernel signature
being checked with CONFIG_KEXEC_VERIFY_SIG enabled.  But kexec-tools use
kexec_load syscall can bypass the checking.

Vivek Goyal proposed to create a common kconfig option so user can compile
in only one syscall for loading kexec kernel.  KEXEC/KEXEC_FILE selects
KEXEC_CORE so that old config files still work.

Because there's general code need CONFIG_KEXEC_CORE, so I updated all the
architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects
KEXEC_CORE in arch Kconfig.  Also updated general kernel code with to
kexec_load syscall.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Dave Young &lt;dyoung@redhat.com&gt;
Cc: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Cc: Vivek Goyal &lt;vgoyal@redhat.com&gt;
Cc: Petr Tesarik &lt;ptesarik@suse.cz&gt;
Cc: Theodore Ts'o &lt;tytso@mit.edu&gt;
Cc: Josh Boyer &lt;jwboyer@fedoraproject.org&gt;
Cc: David Howells &lt;dhowells@redhat.com&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/reboot: Add ASRock Q1900DC-ITX mainboard reboot quirk</title>
<updated>2015-04-01T12:08:09+00:00</updated>
<author>
<name>Stefan Lippers-Hollmann</name>
<email>s.l-h@gmx.de</email>
</author>
<published>2015-03-30T20:44:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=80313b3078fcd2ca51970880d90757f05879a193'/>
<id>80313b3078fcd2ca51970880d90757f05879a193</id>
<content type='text'>
The ASRock Q1900DC-ITX mainboard (Baytrail-D) hangs randomly in
both BIOS and UEFI mode while rebooting unless reboot=pci is
used. Add a quirk to reboot via the pci method.

The problem is very intermittent and hard to debug, it might succeed
rebooting just fine 40 times in a row - but fails half a dozen times
the next day. It seems to be slightly less common in BIOS CSM mode
than native UEFI (with the CSM disabled), but it does happen in either
mode. Since I've started testing this patch in late january, rebooting
has been 100% reliable.

Most of the time it already hangs during POST, but occasionally it
might even make it through the bootloader and the kernel might even
start booting, but then hangs before the mode switch. The same symptoms
occur with grub-efi, gummiboot and grub-pc, just as well as (at least)
kernel 3.16-3.19 and 4.0-rc6 (I haven't tried older kernels than 3.16).
Upgrading to the most current mainboard firmware of the ASRock
Q1900DC-ITX, version 1.20, does not improve the situation.

( Searching the web seems to suggest that other Bay Trail-D mainboards
  might be affected as well. )
--
Signed-off-by: Stefan Lippers-Hollmann &lt;s.l-h@gmx.de&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Cc: Matt Fleming &lt;matt.fleming@intel.com&gt;
Link: http://lkml.kernel.org/r/20150330224427.0fb58e42@mir
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The ASRock Q1900DC-ITX mainboard (Baytrail-D) hangs randomly in
both BIOS and UEFI mode while rebooting unless reboot=pci is
used. Add a quirk to reboot via the pci method.

The problem is very intermittent and hard to debug, it might succeed
rebooting just fine 40 times in a row - but fails half a dozen times
the next day. It seems to be slightly less common in BIOS CSM mode
than native UEFI (with the CSM disabled), but it does happen in either
mode. Since I've started testing this patch in late january, rebooting
has been 100% reliable.

Most of the time it already hangs during POST, but occasionally it
might even make it through the bootloader and the kernel might even
start booting, but then hangs before the mode switch. The same symptoms
occur with grub-efi, gummiboot and grub-pc, just as well as (at least)
kernel 3.16-3.19 and 4.0-rc6 (I haven't tried older kernels than 3.16).
Upgrading to the most current mainboard firmware of the ASRock
Q1900DC-ITX, version 1.20, does not improve the situation.

( Searching the web seems to suggest that other Bay Trail-D mainboards
  might be affected as well. )
--
Signed-off-by: Stefan Lippers-Hollmann &lt;s.l-h@gmx.de&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Cc: Matt Fleming &lt;matt.fleming@intel.com&gt;
Link: http://lkml.kernel.org/r/20150330224427.0fb58e42@mir
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, irq: Move IOAPIC related declarations from hw_irq.h into io_apic.h</title>
<updated>2014-12-16T13:08:17+00:00</updated>
<author>
<name>Jiang Liu</name>
<email>jiang.liu@linux.intel.com</email>
</author>
<published>2014-10-27T08:12:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8643e28da27d6d50f772409b8dc80bdab52239fb'/>
<id>8643e28da27d6d50f772409b8dc80bdab52239fb</id>
<content type='text'>
Clean up code by moving IOAPIC related declarations from hw_irq.h into
io_apic.h.

Signed-off-by: Jiang Liu &lt;jiang.liu@linux.intel.com&gt;
Cc: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Cc: Joerg Roedel &lt;joro@8bytes.org&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Rafael J. Wysocki &lt;rjw@rjwysocki.net&gt;
Cc: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Cc: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Cc: Yinghai Lu &lt;yinghai@kernel.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Prarit Bhargava &lt;prarit@redhat.com&gt;
Cc: Grant Likely &lt;grant.likely@linaro.org&gt;
Cc: Vivek Goyal &lt;vgoyal@redhat.com&gt;
Cc: Baoquan He &lt;bhe@redhat.com&gt;
Cc: Matt Fleming &lt;matt.fleming@intel.com&gt;
Cc: Fenghua Yu &lt;fenghua.yu@intel.com&gt;
Cc: Christian Gmeiner &lt;christian.gmeiner@gmail.com&gt;
Cc: Aubrey &lt;aubrey.li@linux.intel.com&gt;
Cc: Ryan Desfosses &lt;ryan@desfo.org&gt;
Cc: Quentin Lambert &lt;lambert.quentin@gmail.com&gt;
Cc: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Link: http://lkml.kernel.org/r/1414397531-28254-14-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Clean up code by moving IOAPIC related declarations from hw_irq.h into
io_apic.h.

Signed-off-by: Jiang Liu &lt;jiang.liu@linux.intel.com&gt;
Cc: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Cc: Joerg Roedel &lt;joro@8bytes.org&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Rafael J. Wysocki &lt;rjw@rjwysocki.net&gt;
Cc: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Cc: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Cc: Yinghai Lu &lt;yinghai@kernel.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Prarit Bhargava &lt;prarit@redhat.com&gt;
Cc: Grant Likely &lt;grant.likely@linaro.org&gt;
Cc: Vivek Goyal &lt;vgoyal@redhat.com&gt;
Cc: Baoquan He &lt;bhe@redhat.com&gt;
Cc: Matt Fleming &lt;matt.fleming@intel.com&gt;
Cc: Fenghua Yu &lt;fenghua.yu@intel.com&gt;
Cc: Christian Gmeiner &lt;christian.gmeiner@gmail.com&gt;
Cc: Aubrey &lt;aubrey.li@linux.intel.com&gt;
Cc: Ryan Desfosses &lt;ryan@desfo.org&gt;
Cc: Quentin Lambert &lt;lambert.quentin@gmail.com&gt;
Cc: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Link: http://lkml.kernel.org/r/1414397531-28254-14-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>x86/reboot: Add EFI reboot quirk for ACPI Hardware Reduced flag</title>
<updated>2014-07-18T20:23:52+00:00</updated>
<author>
<name>Matt Fleming</name>
<email>matt.fleming@intel.com</email>
</author>
<published>2014-06-13T11:39:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=44be28e9dd9880dca3e2cbf7a844f2114e67f2cb'/>
<id>44be28e9dd9880dca3e2cbf7a844f2114e67f2cb</id>
<content type='text'>
It appears that the BayTrail-T class of hardware requires EFI in order
to powerdown and reboot and no other reliable method exists.

This quirk is generally applicable to all hardware that has the ACPI
Hardware Reduced bit set, since usually ACPI would be the preferred
method.

Cc: Len Brown &lt;len.brown@intel.com&gt;
Cc: Mark Salter &lt;msalter@redhat.com&gt;
Cc: "Rafael J. Wysocki" &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Matt Fleming &lt;matt.fleming@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
It appears that the BayTrail-T class of hardware requires EFI in order
to powerdown and reboot and no other reliable method exists.

This quirk is generally applicable to all hardware that has the ACPI
Hardware Reduced bit set, since usually ACPI would be the preferred
method.

Cc: Len Brown &lt;len.brown@intel.com&gt;
Cc: Mark Salter &lt;msalter@redhat.com&gt;
Cc: "Rafael J. Wysocki" &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Matt Fleming &lt;matt.fleming@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efi/reboot: Add generic wrapper around EfiResetSystem()</title>
<updated>2014-07-18T20:23:51+00:00</updated>
<author>
<name>Matt Fleming</name>
<email>matt.fleming@intel.com</email>
</author>
<published>2014-06-13T11:22:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8562c99cdd30217dea3609e268572f8764f401a5'/>
<id>8562c99cdd30217dea3609e268572f8764f401a5</id>
<content type='text'>
Implement efi_reboot(), which is really just a wrapper around the
EfiResetSystem() EFI runtime service, but it does at least allow us to
funnel all callers through a single location.

It also simplifies the callsites since users no longer need to check to
see whether EFI_RUNTIME_SERVICES are enabled.

Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Tested-by: Mark Salter &lt;msalter@redhat.com&gt;
Signed-off-by: Matt Fleming &lt;matt.fleming@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Implement efi_reboot(), which is really just a wrapper around the
EfiResetSystem() EFI runtime service, but it does at least allow us to
funnel all callers through a single location.

It also simplifies the callsites since users no longer need to check to
see whether EFI_RUNTIME_SERVICES are enabled.

Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Tested-by: Mark Salter &lt;msalter@redhat.com&gt;
Signed-off-by: Matt Fleming &lt;matt.fleming@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/reboot: Add reboot quirk for Certec BPC600</title>
<updated>2014-05-07T09:22:10+00:00</updated>
<author>
<name>Christian Gmeiner</name>
<email>christian.gmeiner@gmail.com</email>
</author>
<published>2014-05-07T07:01:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=aadca6fa4068ad1f92c492bc8507b7ed350825a2'/>
<id>aadca6fa4068ad1f92c492bc8507b7ed350825a2</id>
<content type='text'>
Certec BPC600 needs reboot=pci to actually reboot.

Signed-off-by: Christian Gmeiner &lt;christian.gmeiner@gmail.com&gt;
Cc: Matthew Garrett &lt;mjg59@srcf.ucam.org&gt;
Cc: Li Aubrey &lt;aubrey.li@linux.intel.com&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Dave Jones &lt;davej@redhat.com&gt;
Cc: Fenghua Yu &lt;fenghua.yu@intel.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Link: http://lkml.kernel.org/r/1399446114-2147-1-git-send-email-christian.gmeiner@gmail.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Certec BPC600 needs reboot=pci to actually reboot.

Signed-off-by: Christian Gmeiner &lt;christian.gmeiner@gmail.com&gt;
Cc: Matthew Garrett &lt;mjg59@srcf.ucam.org&gt;
Cc: Li Aubrey &lt;aubrey.li@linux.intel.com&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Dave Jones &lt;davej@redhat.com&gt;
Cc: Fenghua Yu &lt;fenghua.yu@intel.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Link: http://lkml.kernel.org/r/1399446114-2147-1-git-send-email-christian.gmeiner@gmail.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86: Remove the PCI reboot method from the default chain</title>
<updated>2014-04-16T06:56:09+00:00</updated>
<author>
<name>Ingo Molnar</name>
<email>mingo@kernel.org</email>
</author>
<published>2014-04-04T06:41:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=5be44a6fb1edb57d7d2d77151870dcd79c8c0e58'/>
<id>5be44a6fb1edb57d7d2d77151870dcd79c8c0e58</id>
<content type='text'>
Steve reported a reboot hang and bisected it back to this commit:

  a4f1987e4c54 x86, reboot: Add EFI and CF9 reboot methods into the default list

He heroically tested all reboot methods and found the following:

  reboot=t       # triple fault                  ok
  reboot=k       # keyboard ctrl                 FAIL
  reboot=b       # BIOS                          ok
  reboot=a       # ACPI                          FAIL
  reboot=e       # EFI                           FAIL   [system has no EFI]
  reboot=p       # PCI 0xcf9                     FAIL

And I think it's pretty obvious that we should only try PCI 0xcf9 as a
last resort - if at all.

The other observation is that (on this box) we should never try
the PCI reboot method, but close with either the 'triple fault'
or the 'BIOS' (terminal!) reboot methods.

Thirdly, CF9_COND is a total misnomer - it should be something like
CF9_SAFE or CF9_CAREFUL, and 'CF9' should be 'CF9_FORCE' ...

So this patch fixes the worst problems:

 - it orders the actual reboot logic to follow the reboot ordering
   pattern - it was in a pretty random order before for no good
   reason.

 - it fixes the CF9 misnomers and uses BOOT_CF9_FORCE and
   BOOT_CF9_SAFE flags to make the code more obvious.

 - it tries the BIOS reboot method before the PCI reboot method.
   (Since 'BIOS' is a terminal reboot method resulting in a hang
    if it does not work, this is essentially equivalent to removing
    the PCI reboot method from the default reboot chain.)

 - just for the miraculous possibility of terminal (resulting
   in hang) reboot methods of triple fault or BIOS returning
   without having done their job, there's an ordering between
   them as well.

Reported-and-bisected-and-tested-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Li Aubrey &lt;aubrey.li@linux.intel.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Matthew Garrett &lt;mjg59@srcf.ucam.org&gt;
Link: http://lkml.kernel.org/r/20140404064120.GB11877@gmail.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Steve reported a reboot hang and bisected it back to this commit:

  a4f1987e4c54 x86, reboot: Add EFI and CF9 reboot methods into the default list

He heroically tested all reboot methods and found the following:

  reboot=t       # triple fault                  ok
  reboot=k       # keyboard ctrl                 FAIL
  reboot=b       # BIOS                          ok
  reboot=a       # ACPI                          FAIL
  reboot=e       # EFI                           FAIL   [system has no EFI]
  reboot=p       # PCI 0xcf9                     FAIL

And I think it's pretty obvious that we should only try PCI 0xcf9 as a
last resort - if at all.

The other observation is that (on this box) we should never try
the PCI reboot method, but close with either the 'triple fault'
or the 'BIOS' (terminal!) reboot methods.

Thirdly, CF9_COND is a total misnomer - it should be something like
CF9_SAFE or CF9_CAREFUL, and 'CF9' should be 'CF9_FORCE' ...

So this patch fixes the worst problems:

 - it orders the actual reboot logic to follow the reboot ordering
   pattern - it was in a pretty random order before for no good
   reason.

 - it fixes the CF9 misnomers and uses BOOT_CF9_FORCE and
   BOOT_CF9_SAFE flags to make the code more obvious.

 - it tries the BIOS reboot method before the PCI reboot method.
   (Since 'BIOS' is a terminal reboot method resulting in a hang
    if it does not work, this is essentially equivalent to removing
    the PCI reboot method from the default reboot chain.)

 - just for the miraculous possibility of terminal (resulting
   in hang) reboot methods of triple fault or BIOS returning
   without having done their job, there's an ordering between
   them as well.

Reported-and-bisected-and-tested-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Li Aubrey &lt;aubrey.li@linux.intel.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Matthew Garrett &lt;mjg59@srcf.ucam.org&gt;
Link: http://lkml.kernel.org/r/20140404064120.GB11877@gmail.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, reboot: Only use CF9_COND automatically, not CF9</title>
<updated>2014-03-05T23:41:15+00:00</updated>
<author>
<name>H. Peter Anvin</name>
<email>hpa@linux.intel.com</email>
</author>
<published>2014-03-05T23:41:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=fb3bd7b19b2b6ef779d18573c10c00c53cd8add6'/>
<id>fb3bd7b19b2b6ef779d18573c10c00c53cd8add6</id>
<content type='text'>
Only CF9_COND is appropriate for inclusion in the default chain, not
CF9; the latter will poke that register unconditionally, whereas
CF9_COND will at least look for PCI configuration method #1 or #2
first (a weak check, but better than nothing.)

CF9 should be used for explicit system configuration (command line or
DMI) only.

Cc: Aubrey Li &lt;aubrey.li@intel.com&gt;
Cc: Matthew Garrett &lt;mjg59@srcf.ucam.org&gt;
Link: http://lkml.kernel.org/r/53130A46.1010801@linux.intel.com
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Only CF9_COND is appropriate for inclusion in the default chain, not
CF9; the latter will poke that register unconditionally, whereas
CF9_COND will at least look for PCI configuration method #1 or #2
first (a weak check, but better than nothing.)

CF9 should be used for explicit system configuration (command line or
DMI) only.

Cc: Aubrey Li &lt;aubrey.li@intel.com&gt;
Cc: Matthew Garrett &lt;mjg59@srcf.ucam.org&gt;
Link: http://lkml.kernel.org/r/53130A46.1010801@linux.intel.com
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, reboot: Add EFI and CF9 reboot methods into the default list</title>
<updated>2014-03-05T23:27:07+00:00</updated>
<author>
<name>Li, Aubrey</name>
<email>aubrey.li@linux.intel.com</email>
</author>
<published>2014-03-02T10:39:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a4f1987e4c5489a3877eaa7451a68d28c5a3f664'/>
<id>a4f1987e4c5489a3877eaa7451a68d28c5a3f664</id>
<content type='text'>
Reboot is the last service linux OS provides to the end user. We are
supposed to make this function more robust than today. This patch adds
all of the known reboot methods into the default attempt list. The
machines requiring reboot=efi or reboot=p or reboot=bios get a chance
to reboot automatically now.

If there is a new reboot method emerged, we are supposed to add it to
the default list as well, instead of adding the endless dmidecode entry.

If one method required is in the default list in this patch but the
machine reboot still hangs, that means some methods ahead of the
required method cause the system hangs, then reboot the machine by
passing reboot= arguments and submit the reboot dmidecode table quirk.

We are supposed to remove the reboot dmidecode table from the kernel,
but to be safe, we keep it. This patch prevents us from adding more.
If you happened to have a machine listed in the reboot dmidecode
table and this patch makes reboot work on your machine, please submit
a patch to remove the quirk.

The default reboot order with this patch is now:

    ACPI &gt; KBD &gt; ACPI &gt; KBD &gt; EFI &gt; CF9_COND &gt; BIOS

Because BIOS and TRIPLE are mutually exclusive (either will either
work or hang the machine) that method is not included.

[ hpa: as with any changes to the reboot order, this patch will have
  to be monitored carefully for regressions. ]

Signed-off-by: Aubrey Li &lt;aubrey.li@intel.com&gt;
Acked-by: Matthew Garrett &lt;mjg59@srcf.ucam.org&gt;
Link: http://lkml.kernel.org/r/53130A46.1010801@linux.intel.com
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Reboot is the last service linux OS provides to the end user. We are
supposed to make this function more robust than today. This patch adds
all of the known reboot methods into the default attempt list. The
machines requiring reboot=efi or reboot=p or reboot=bios get a chance
to reboot automatically now.

If there is a new reboot method emerged, we are supposed to add it to
the default list as well, instead of adding the endless dmidecode entry.

If one method required is in the default list in this patch but the
machine reboot still hangs, that means some methods ahead of the
required method cause the system hangs, then reboot the machine by
passing reboot= arguments and submit the reboot dmidecode table quirk.

We are supposed to remove the reboot dmidecode table from the kernel,
but to be safe, we keep it. This patch prevents us from adding more.
If you happened to have a machine listed in the reboot dmidecode
table and this patch makes reboot work on your machine, please submit
a patch to remove the quirk.

The default reboot order with this patch is now:

    ACPI &gt; KBD &gt; ACPI &gt; KBD &gt; EFI &gt; CF9_COND &gt; BIOS

Because BIOS and TRIPLE are mutually exclusive (either will either
work or hang the machine) that method is not included.

[ hpa: as with any changes to the reboot order, this patch will have
  to be monitored carefully for regressions. ]

Signed-off-by: Aubrey Li &lt;aubrey.li@intel.com&gt;
Acked-by: Matthew Garrett &lt;mjg59@srcf.ucam.org&gt;
Link: http://lkml.kernel.org/r/53130A46.1010801@linux.intel.com
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
