Reboot hangs on VersaLogic Ocelot

Reboot hangs on VersaLogic Ocelot

[Michael D Labriola]

I've been troubleshooting a VersaLogic Ocelot SBC that's been hanging
on reboot ever since I upgraded its BIOS.  The conclusion I've come to
is that commit e19e074 (x86: Fix reboot problem on VersaLogic Menlow
boards) needs to be reverted.

My system was rebooting fine (kernel v3.2) prior to upgrading the
BIOS, but it turns out that the DMI string being looked for in the
VersaLogic reboot quirk wasn't added until I upgraded the BIOS.

Here's a summary of the behavior I encountered on my system
(VL-EPMs-21a rev 1.00 w/ BIOS 6.5.102)

- v2.6.37 reboot=bios is needed

- v2.6.38-rc1: behavior changed, reboot=acpi is needed, reboot=kbd and
  reboot=bios result in system hang.

- v2.6.38: VersaLogic patch (e19e074 x86: Fix reboot problem on
  VersaLogic Menlow boards) was applied prior to v2.6.38-rc7.  This
  patch sets a quirk for VersaLogic Menlow boards that forces the use
  of reboot=bios, which doesn't work anymore.  As far as I can tell,
  there's no way to override this faulty quirk, as it seems to take
  precedence over the reboot= argument.

- v3.2: It seems that commit 660e34c (x86: Reorder reboot method
  preferences) changed the default reboot method to acpi prior to
  v3.0-rc1, which means the default behavior is appropriate for the
  Ocelot.  After reverting commit e19e074, my system reboots perfectly
  w/out passing any reboot= arguments.  I confirmed that this is a
  true statement for all 3 versions of the Ocelot's BIOS.

---
Michael D Labriola
Electric Boat
mlabriol@gdeb.com
401-848-8871 (desk)
401-848-8513 (lab)
401-316-9844 (cell)


 

Re: Reboot hangs on VersaLogic Ocelot

[Ingo Molnar]

(Cc:-ed Matthew Garrett)

* Michael D Labriola <mlabriol@gdeb.com> wrote:

> I've been troubleshooting a VersaLogic Ocelot SBC that's been 
> hanging on reboot ever since I upgraded its BIOS.  The 
> conclusion I've come to is that commit e19e074 (x86: Fix 
> reboot problem on VersaLogic Menlow boards) needs to be 
> reverted.
>
> My system was rebooting fine (kernel v3.2) prior to upgrading 
> the BIOS, but it turns out that the DMI string being looked 
> for in the VersaLogic reboot quirk wasn't added until I 
> upgraded the BIOS.
> 
> Here's a summary of the behavior I encountered on my system 
> (VL-EPMs-21a rev 1.00 w/ BIOS 6.5.102)
> 
> - v2.6.37 reboot=bios is needed
> 
> - v2.6.38-rc1: behavior changed, reboot=acpi is needed, reboot=kbd and
>   reboot=bios result in system hang.
> 
> - v2.6.38: VersaLogic patch (e19e074 x86: Fix reboot problem on
>   VersaLogic Menlow boards) was applied prior to v2.6.38-rc7.  This
>   patch sets a quirk for VersaLogic Menlow boards that forces the use
>   of reboot=bios, which doesn't work anymore.  As far as I can tell,
>   there's no way to override this faulty quirk, as it seems to take
>   precedence over the reboot= argument.

That's another bug i'd argue - the user specifying something on 
the boot command line should *always* override the kernel's 
built-in defaults.

> - v3.2: It seems that commit 660e34c (x86: Reorder reboot method
>   preferences) changed the default reboot method to acpi prior to
>   v3.0-rc1, which means the default behavior is appropriate for the
>   Ocelot.  After reverting commit e19e074, my system reboots perfectly
>   w/out passing any reboot= arguments.  I confirmed that this is a
>   true statement for all 3 versions of the Ocelot's BIOS.

And this works for the older BIOS version as well, the one which 
motivated commit e19e074?

Please send a patch that removes the quirk (not named a revert - 
as technically the old quirk did solve problems), with the 
changelog containing your (excellent) bug analysis and the test 
coverage above, plus a signoff?

Matthew, do you concur? Looks like your reordering changes 
actively improved the default behavior and we can start removing 
quirks.

Thanks,

	Ingo

Re: Reboot hangs on VersaLogic Ocelot

[Michael D Labriola]

Ingo Molnar <mingo@elte.hu> wrote on 01/16/2012 02:53:48 AM:

> From: Ingo Molnar <mingo@elte.hu>
> To: Michael D Labriola <mlabriol@gdeb.com>, Matthew Garrett 
<mjg@redhat.com>
> Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar 
> <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>, 
> x86@kernel.org, linux-kernel@vger.kernel.org, Kushal Koolwal 
> <kushalkoolwal@gmail.com>, support@versalogic.com, 
> michael.d.labriola@gmail.com
> Date: 01/16/2012 02:54 AM
> Subject: Re: Reboot hangs on VersaLogic Ocelot
> 
> 
> (Cc:-ed Matthew Garrett)
> 
> * Michael D Labriola <mlabriol@gdeb.com> wrote:
> 
> > I've been troubleshooting a VersaLogic Ocelot SBC that's been 
> > hanging on reboot ever since I upgraded its BIOS.  The 
> > conclusion I've come to is that commit e19e074 (x86: Fix 
> > reboot problem on VersaLogic Menlow boards) needs to be 
> > reverted.
> >
> > My system was rebooting fine (kernel v3.2) prior to upgrading 
> > the BIOS, but it turns out that the DMI string being looked 
> > for in the VersaLogic reboot quirk wasn't added until I 
> > upgraded the BIOS.
> > 
> > Here's a summary of the behavior I encountered on my system 
> > (VL-EPMs-21a rev 1.00 w/ BIOS 6.5.102)
> > 
> > - v2.6.37 reboot=bios is needed
> > 
> > - v2.6.38-rc1: behavior changed, reboot=acpi is needed, reboot=kbd and
> >   reboot=bios result in system hang.
> > 
> > - v2.6.38: VersaLogic patch (e19e074 x86: Fix reboot problem on
> >   VersaLogic Menlow boards) was applied prior to v2.6.38-rc7.  This
> >   patch sets a quirk for VersaLogic Menlow boards that forces the use
> >   of reboot=bios, which doesn't work anymore.  As far as I can tell,
> >   there's no way to override this faulty quirk, as it seems to take
> >   precedence over the reboot= argument.
> 
> That's another bug i'd argue - the user specifying something on 
> the boot command line should *always* override the kernel's 
> built-in defaults.

Agreed.  This would have taken me about 5 mins to troubleshoot if I'd 
realized up front that passing reboot= args on command line was being 
overridden by this quirk.  The obvious first thing to do was try all the 
available options... none of which had any effect.  I've got a patch to 
change this behavior as well (DMI scanning for quirks *only* happens if 
user didn't pass a reboot= option on the command line).

> > - v3.2: It seems that commit 660e34c (x86: Reorder reboot method
> >   preferences) changed the default reboot method to acpi prior to
> >   v3.0-rc1, which means the default behavior is appropriate for the
> >   Ocelot.  After reverting commit e19e074, my system reboots perfectly
> >   w/out passing any reboot= arguments.  I confirmed that this is a
> >   true statement for all 3 versions of the Ocelot's BIOS.
> 
> And this works for the older BIOS version as well, the one which 
> motivated commit e19e074?

Versions of the BIOS prior to 6.5.102 set the DMI information to something 
the quirk wasn't looking for, so that's actually the only applicable BIOS 
rev.  Older versions can all be rebooted by passing 
reboot=whatever_worked_in_that_version.

> Please send a patch that removes the quirk (not named a revert - 
> as technically the old quirk did solve problems), with the 
> changelog containing your (excellent) bug analysis and the test 
> coverage above, plus a signoff?

Will do, hopefully this afternoon.

> Matthew, do you concur? Looks like your reordering changes 
> actively improved the default behavior and we can start removing 
> quirks.
> 
> Thanks,
> 
>    Ingo

---
Michael D Labriola
Electric Boat
mlabriol@gdeb.com
401-848-8871 (desk)
401-848-8513 (lab)
401-316-9844 (cell)




 

Re: Reboot hangs on VersaLogic Ocelot

[Michael D Labriola]

Michael D Labriola/EB/GDYN wrote on 01/16/2012 11:51:05 AM:

> From: Michael D Labriola/EB/GDYN
> To: Ingo Molnar <mingo@elte.hu>
> Cc: "H. Peter Anvin" <hpa@zytor.com>, Kushal Koolwal 
> <kushalkoolwal@gmail.com>, linux-kernel@vger.kernel.org, 
> michael.d.labriola@gmail.com, Ingo Molnar <mingo@redhat.com>, 
> Matthew Garrett <mjg@redhat.com>, support@versalogic.com, Thomas 
> Gleixner <tglx@linutronix.de>, x86@kernel.org
> Date: 01/16/2012 11:51 AM
> Subject: Re: Reboot hangs on VersaLogic Ocelot
> 
> Ingo Molnar <mingo@elte.hu> wrote on 01/16/2012 02:53:48 AM:
> 
> > From: Ingo Molnar <mingo@elte.hu>
> > To: Michael D Labriola <mlabriol@gdeb.com>, Matthew Garrett 
<mjg@redhat.com>
> > Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar 
> > <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>, 
> > x86@kernel.org, linux-kernel@vger.kernel.org, Kushal Koolwal 
> > <kushalkoolwal@gmail.com>, support@versalogic.com, 
> > michael.d.labriola@gmail.com
> > Date: 01/16/2012 02:54 AM
> > Subject: Re: Reboot hangs on VersaLogic Ocelot
> > 
> > 
> > (Cc:-ed Matthew Garrett)
> > 
> > * Michael D Labriola <mlabriol@gdeb.com> wrote:
> > 
> > > I've been troubleshooting a VersaLogic Ocelot SBC that's been 
> > > hanging on reboot ever since I upgraded its BIOS.  The 
> > > conclusion I've come to is that commit e19e074 (x86: Fix 
> > > reboot problem on VersaLogic Menlow boards) needs to be 
> > > reverted.
> > >
> > > My system was rebooting fine (kernel v3.2) prior to upgrading 
> > > the BIOS, but it turns out that the DMI string being looked 
> > > for in the VersaLogic reboot quirk wasn't added until I 
> > > upgraded the BIOS.
> > > 
> > > Here's a summary of the behavior I encountered on my system 
> > > (VL-EPMs-21a rev 1.00 w/ BIOS 6.5.102)
> > > 
> > > - v2.6.37 reboot=bios is needed
> > > 
> > > - v2.6.38-rc1: behavior changed, reboot=acpi is needed, reboot=kbd 
and
> > >   reboot=bios result in system hang.
> > > 
> > > - v2.6.38: VersaLogic patch (e19e074 x86: Fix reboot problem on
> > >   VersaLogic Menlow boards) was applied prior to v2.6.38-rc7.  This
> > >   patch sets a quirk for VersaLogic Menlow boards that forces the 
use
> > >   of reboot=bios, which doesn't work anymore.  As far as I can tell,
> > >   there's no way to override this faulty quirk, as it seems to take
> > >   precedence over the reboot= argument.
> > 
> > That's another bug i'd argue - the user specifying something on 
> > the boot command line should *always* override the kernel's 
> > built-in defaults.

> Agreed.  This would have taken me about 5 mins to troubleshoot if 
> I'd realized up front that passing reboot= args on command line was 
> being overridden by this quirk.  The obvious first thing to do was 
> try all the available options... none of which had any effect.  I've
> got a patch to change this behavior as well (DMI scanning for quirks
> *only* happens if user didn't pass a reboot= option on the command 
line).
> 
> > > - v3.2: It seems that commit 660e34c (x86: Reorder reboot method
> > >   preferences) changed the default reboot method to acpi prior to
> > >   v3.0-rc1, which means the default behavior is appropriate for the
> > >   Ocelot.  After reverting commit e19e074, my system reboots 
perfectly
> > >   w/out passing any reboot= arguments.  I confirmed that this is a
> > >   true statement for all 3 versions of the Ocelot's BIOS.
> > 
> > And this works for the older BIOS version as well, the one which 
> > motivated commit e19e074?

> Versions of the BIOS prior to 6.5.102 set the DMI information to 
> something the quirk wasn't looking for, so that's actually the only 
> applicable BIOS rev.  Older versions can all be rebooted by passing 
> reboot=whatever_worked_in_that_version.
> 
> > Please send a patch that removes the quirk (not named a revert - 
> > as technically the old quirk did solve problems), with the 
> > changelog containing your (excellent) bug analysis and the test 
> > coverage above, plus a signoff?

> Will do, hopefully this afternoon.
> 
> > Matthew, do you concur? Looks like your reordering changes 
> > actively improved the default behavior and we can start removing 
> > quirks.
> > 
> > Thanks,
> > 
> >    Ingo
> 

Actually, assuming we fix the bios= argument ignored by DMI scan problem, 
would it be better to change the VersaLogic quirk to acpi even though it's 
not necessary right now?  If the default reboot method ever switches from 
acpi to kbd or bios, these boards will hang on reboot again...

---
Michael D Labriola
Electric Boat
mlabriol@gdeb.com
401-848-8871 (desk)
401-848-8513 (lab)
401-316-9844 (cell)




 

Re: Reboot hangs on VersaLogic Ocelot

[Matthew Garrett]

On Mon, Jan 16, 2012 at 12:20:45PM -0500, Michael D Labriola wrote:
> Actually, assuming we fix the bios= argument ignored by DMI scan problem, 
> would it be better to change the VersaLogic quirk to acpi even though it's 
> not necessary right now?  If the default reboot method ever switches from 
> acpi to kbd or bios, these boards will hang on reboot again...

A lot of hardware relies on the acpi method being used. I don't see us 
changing the default for x86 when booted via BIOS.

-- 
Matthew Garrett | mjg59@srcf.ucam.org

Re: Reboot hangs on VersaLogic Ocelot

[Ingo Molnar]

* Matthew Garrett <mjg59@srcf.ucam.org> wrote:

> On Mon, Jan 16, 2012 at 12:20:45PM -0500, Michael D Labriola wrote:

> > Actually, assuming we fix the bios= argument ignored by DMI 
> > scan problem, would it be better to change the VersaLogic 
> > quirk to acpi even though it's not necessary right now?  If 
> > the default reboot method ever switches from acpi to kbd or 
> > bios, these boards will hang on reboot again...
> 
> A lot of hardware relies on the acpi method being used. I 
> don't see us changing the default for x86 when booted via 
> BIOS.

Yeah, i don't think we'll ever again switch away from ACPI being 
the default for currently existing hardware.

(Far-)future hardware might have different defaults, but that 
won't affect hardware that exists today.

Thanks,

	Ingo

Re: Reboot hangs on VersaLogic Ocelot

[Michael D Labriola]

Ingo Molnar <mingo@elte.hu> wrote on 01/17/2012 03:57:56 AM:

> From: Ingo Molnar <mingo@elte.hu>
> To: Matthew Garrett <mjg59@srcf.ucam.org>
> Cc: Michael D Labriola <mlabriol@gdeb.com>, "H. Peter Anvin" 
> <hpa@zytor.com>, Kushal Koolwal <kushalkoolwal@gmail.com>, linux-
> kernel@vger.kernel.org, michael.d.labriola@gmail.com, 
> support@versalogic.com, Thomas Gleixner <tglx@linutronix.de>, 
x86@kernel.org
> Date: 01/17/2012 04:04 AM
> Subject: Re: Reboot hangs on VersaLogic Ocelot
> 
> 
> * Matthew Garrett <mjg59@srcf.ucam.org> wrote:
> 
> > On Mon, Jan 16, 2012 at 12:20:45PM -0500, Michael D Labriola wrote:
> 
> > > Actually, assuming we fix the bios= argument ignored by DMI 
> > > scan problem, would it be better to change the VersaLogic 
> > > quirk to acpi even though it's not necessary right now?  If 
> > > the default reboot method ever switches from acpi to kbd or 
> > > bios, these boards will hang on reboot again...
> > 
> > A lot of hardware relies on the acpi method being used. I 
> > don't see us changing the default for x86 when booted via 
> > BIOS.
> 
> Yeah, i don't think we'll ever again switch away from ACPI being 
> the default for currently existing hardware.
> 
> (Far-)future hardware might have different defaults, but that 
> won't affect hardware that exists today.
> 
> Thanks,
> 
>    Ingo

Ingo,

I sent the aforementioned patches last night using git-send-email... but 
I'm not sure they went through correctly.  I got the email at my home 
account, but not my work account, and they don't seem to be in the LKML 
archives.  Did anyone get them?  I listed all the addresses on this 
email's distro with separate --to and --cc arguments and tried to use an 
appropriate In-Reply-To Message-Id when prompted, but maybe I messed it 
up.

Also, how does the sign-off work?  Does the appropriate person (Matthew?) 
review the patches and re-submit with a sign-off field?

---
Michael D Labriola
Electric Boat
mlabriol@gdeb.com
401-848-8871 (desk)
401-848-8513 (lab)
401-316-9844 (cell)




 

Re: Reboot hangs on VersaLogic Ocelot

[Michael D Labriola]

Michael D Labriola/EB/GDYN wrote on 01/17/2012 09:22:25 AM:

> From: Michael D Labriola/EB/GDYN
> To: Ingo Molnar <mingo@elte.hu>
> Cc: "H. Peter Anvin" <hpa@zytor.com>, Kushal Koolwal 
> <kushalkoolwal@gmail.com>, linux-kernel@vger.kernel.org, 
> michael.d.labriola@gmail.com, Matthew Garrett <mjg59@srcf.ucam.org>,
> support@versalogic.com, Thomas Gleixner <tglx@linutronix.de>, 
x86@kernel.org
> Date: 01/17/2012 09:22 AM
> Subject: Re: Reboot hangs on VersaLogic Ocelot
> 
> Ingo Molnar <mingo@elte.hu> wrote on 01/17/2012 03:57:56 AM:
> 
> > From: Ingo Molnar <mingo@elte.hu>
> > To: Matthew Garrett <mjg59@srcf.ucam.org>
> > Cc: Michael D Labriola <mlabriol@gdeb.com>, "H. Peter Anvin" 
> > <hpa@zytor.com>, Kushal Koolwal <kushalkoolwal@gmail.com>, linux-
> > kernel@vger.kernel.org, michael.d.labriola@gmail.com, 
> > support@versalogic.com, Thomas Gleixner <tglx@linutronix.de>, 
x86@kernel.org
> > Date: 01/17/2012 04:04 AM
> > Subject: Re: Reboot hangs on VersaLogic Ocelot
> > 
> > 
> > * Matthew Garrett <mjg59@srcf.ucam.org> wrote:
> > 
> > > On Mon, Jan 16, 2012 at 12:20:45PM -0500, Michael D Labriola wrote:
> > 
> > > > Actually, assuming we fix the bios= argument ignored by DMI 
> > > > scan problem, would it be better to change the VersaLogic 
> > > > quirk to acpi even though it's not necessary right now?  If 
> > > > the default reboot method ever switches from acpi to kbd or 
> > > > bios, these boards will hang on reboot again...
> > > 
> > > A lot of hardware relies on the acpi method being used. I 
> > > don't see us changing the default for x86 when booted via 
> > > BIOS.
> > 
> > Yeah, i don't think we'll ever again switch away from ACPI being 
> > the default for currently existing hardware.
> > 
> > (Far-)future hardware might have different defaults, but that 
> > won't affect hardware that exists today.
> > 
> > Thanks,
> > 
> >    Ingo
> 
> Ingo,
> 
> I sent the aforementioned patches last night using git-send-email...
> but I'm not sure they went through correctly.  I got the email at my
> home account, but not my work account, and they don't seem to be in 
> the LKML archives.  Did anyone get them?  I listed all the addresses
> on this email's distro with separate --to and --cc arguments and 
> tried to use an appropriate In-Reply-To Message-Id when prompted, 
> but maybe I messed it up.
> 
> Also, how does the sign-off work?  Does the appropriate person 
> (Matthew?) review the patches and re-submit with a sign-off field?

OK, I've resent the patches from my work email (Lotus Notes! Fingers 
crossed!!).  New patches include sign-off from myself.

---
Michael D Labriola
Electric Boat
mlabriol@gdeb.com
401-848-8871 (desk)
401-848-8513 (lab)
401-316-9844 (cell)




 

Re: Reboot hangs on VersaLogic Ocelot

[Matthew Garrett]

On Mon, Jan 16, 2012 at 08:53:48AM +0100, Ingo Molnar wrote:
> Please send a patch that removes the quirk (not named a revert - 
> as technically the old quirk did solve problems), with the 
> changelog containing your (excellent) bug analysis and the test 
> coverage above, plus a signoff?
> 
> Matthew, do you concur? Looks like your reordering changes 
> actively improved the default behavior and we can start removing 
> quirks.

Well, that was certainly the aim. Dropping the quirk here should be 
correct.

-- 
Matthew Garrett | mjg59@srcf.ucam.org