* [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
@ 2016-01-28 11:08 ` Will Deacon
0 siblings, 0 replies; 18+ messages in thread
From: Will Deacon @ 2016-01-28 11:08 UTC (permalink / raw)
To: linux-arm-kernel
On Thu, Jan 28, 2016 at 10:34:41AM +0000, Catalin Marinas wrote:
> On Wed, Jan 27, 2016 at 04:10:30PM -0700, dann frazier wrote:
> > 16K page size is an optional feature of the architecture, and is not
> > supported by the X-Gene SoC family.
> >
> > Signed-off-by: dann frazier <dann.frazier@canonical.com>
> > ---
> > arch/arm64/Kconfig.platforms | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/arch/arm64/Kconfig.platforms b/arch/arm64/Kconfig.platforms
> > index 21074f6..b241290 100644
> > --- a/arch/arm64/Kconfig.platforms
> > +++ b/arch/arm64/Kconfig.platforms
> > @@ -133,6 +133,7 @@ config ARCH_VEXPRESS
> >
> > config ARCH_XGENE
> > bool "AppliedMicro X-Gene SOC Family"
> > + depends on !ARM64_16K_PAGES
> > help
> > This enables support for AppliedMicro X-Gene SOC Family
>
> This would be the case on Juno as well. But maybe at some point the
> X-Gene family would gain a CPU with such support.
>
> Anyway, I would rather make 16K pages depend on EXPERT, make it a bit
> harder to enable. We've had a few questions recently about enabling it
> on CPUs that don't have such feature.
I thought there was also a suggestion that we could fail gracefully in
the EFI stub if we detected an unsupported page size?
Will
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
2016-01-28 11:08 ` Will Deacon
@ 2016-01-28 11:20 ` Mark Rutland
-1 siblings, 0 replies; 18+ messages in thread
From: Mark Rutland @ 2016-01-28 11:20 UTC (permalink / raw)
To: Will Deacon, ard.biesheuvel, jeremy.linton
Cc: Catalin Marinas, Feng Kan, dann frazier, Duc Dang, linux-kernel,
Loc Ho, Kumar Sankaran, linux-arm-kernel
On Thu, Jan 28, 2016 at 11:08:20AM +0000, Will Deacon wrote:
> On Thu, Jan 28, 2016 at 10:34:41AM +0000, Catalin Marinas wrote:
> > On Wed, Jan 27, 2016 at 04:10:30PM -0700, dann frazier wrote:
> > > 16K page size is an optional feature of the architecture, and is not
> > > supported by the X-Gene SoC family.
> > >
> > > Signed-off-by: dann frazier <dann.frazier@canonical.com>
> > > ---
> > > arch/arm64/Kconfig.platforms | 1 +
> > > 1 file changed, 1 insertion(+)
> > >
> > > diff --git a/arch/arm64/Kconfig.platforms b/arch/arm64/Kconfig.platforms
> > > index 21074f6..b241290 100644
> > > --- a/arch/arm64/Kconfig.platforms
> > > +++ b/arch/arm64/Kconfig.platforms
> > > @@ -133,6 +133,7 @@ config ARCH_VEXPRESS
> > >
> > > config ARCH_XGENE
> > > bool "AppliedMicro X-Gene SOC Family"
> > > + depends on !ARM64_16K_PAGES
> > > help
> > > This enables support for AppliedMicro X-Gene SOC Family
> >
> > This would be the case on Juno as well. But maybe at some point the
> > X-Gene family would gain a CPU with such support.
> >
> > Anyway, I would rather make 16K pages depend on EXPERT, make it a bit
> > harder to enable. We've had a few questions recently about enabling it
> > on CPUs that don't have such feature.
>
> I thought there was also a suggestion that we could fail gracefully in
> the EFI stub if we detected an unsupported page size?
Yup. There are other things we could/should test, too.
I believe Jeremy had a patch, but due to churn in that area it didn't
get picked up.
Mark.
^ permalink raw reply [flat|nested] 18+ messages in thread
* [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
@ 2016-01-28 11:20 ` Mark Rutland
0 siblings, 0 replies; 18+ messages in thread
From: Mark Rutland @ 2016-01-28 11:20 UTC (permalink / raw)
To: linux-arm-kernel
On Thu, Jan 28, 2016 at 11:08:20AM +0000, Will Deacon wrote:
> On Thu, Jan 28, 2016 at 10:34:41AM +0000, Catalin Marinas wrote:
> > On Wed, Jan 27, 2016 at 04:10:30PM -0700, dann frazier wrote:
> > > 16K page size is an optional feature of the architecture, and is not
> > > supported by the X-Gene SoC family.
> > >
> > > Signed-off-by: dann frazier <dann.frazier@canonical.com>
> > > ---
> > > arch/arm64/Kconfig.platforms | 1 +
> > > 1 file changed, 1 insertion(+)
> > >
> > > diff --git a/arch/arm64/Kconfig.platforms b/arch/arm64/Kconfig.platforms
> > > index 21074f6..b241290 100644
> > > --- a/arch/arm64/Kconfig.platforms
> > > +++ b/arch/arm64/Kconfig.platforms
> > > @@ -133,6 +133,7 @@ config ARCH_VEXPRESS
> > >
> > > config ARCH_XGENE
> > > bool "AppliedMicro X-Gene SOC Family"
> > > + depends on !ARM64_16K_PAGES
> > > help
> > > This enables support for AppliedMicro X-Gene SOC Family
> >
> > This would be the case on Juno as well. But maybe at some point the
> > X-Gene family would gain a CPU with such support.
> >
> > Anyway, I would rather make 16K pages depend on EXPERT, make it a bit
> > harder to enable. We've had a few questions recently about enabling it
> > on CPUs that don't have such feature.
>
> I thought there was also a suggestion that we could fail gracefully in
> the EFI stub if we detected an unsupported page size?
Yup. There are other things we could/should test, too.
I believe Jeremy had a patch, but due to churn in that area it didn't
get picked up.
Mark.
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
2016-01-28 11:20 ` Mark Rutland
@ 2016-01-28 14:50 ` Jeremy Linton
-1 siblings, 0 replies; 18+ messages in thread
From: Jeremy Linton @ 2016-01-28 14:50 UTC (permalink / raw)
To: Mark Rutland, Will Deacon, ard.biesheuvel
Cc: Catalin Marinas, Feng Kan, dann frazier, Duc Dang, linux-kernel,
Loc Ho, Kumar Sankaran, linux-arm-kernel
On 01/28/2016 05:20 AM, Mark Rutland wrote:
> On Thu, Jan 28, 2016 at 11:08:20AM +0000, Will Deacon wrote:
>> On Thu, Jan 28, 2016 at 10:34:41AM +0000, Catalin Marinas wrote:
>> I thought there was also a suggestion that we could fail gracefully in
>> the EFI stub if we detected an unsupported page size?
>
> Yup. There are other things we could/should test, too.
>
> I believe Jeremy had a patch, but due to churn in that area it didn't
> get picked up.
I will clean-up and re-post that patch in the future too. It was fairly
trivial so if someone feels the need for immediately...
https://lkml.org/lkml/2015/10/14/948
IMHO, The main sticking point initially was that the correct place for
the check was a moving target. That problem has been fixed, so it should
be easy to move it.
^ permalink raw reply [flat|nested] 18+ messages in thread
* [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
@ 2016-01-28 14:50 ` Jeremy Linton
0 siblings, 0 replies; 18+ messages in thread
From: Jeremy Linton @ 2016-01-28 14:50 UTC (permalink / raw)
To: linux-arm-kernel
On 01/28/2016 05:20 AM, Mark Rutland wrote:
> On Thu, Jan 28, 2016 at 11:08:20AM +0000, Will Deacon wrote:
>> On Thu, Jan 28, 2016 at 10:34:41AM +0000, Catalin Marinas wrote:
>> I thought there was also a suggestion that we could fail gracefully in
>> the EFI stub if we detected an unsupported page size?
>
> Yup. There are other things we could/should test, too.
>
> I believe Jeremy had a patch, but due to churn in that area it didn't
> get picked up.
I will clean-up and re-post that patch in the future too. It was fairly
trivial so if someone feels the need for immediately...
https://lkml.org/lkml/2015/10/14/948
IMHO, The main sticking point initially was that the correct place for
the check was a moving target. That problem has been fixed, so it should
be easy to move it.
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
2016-01-28 11:08 ` Will Deacon
@ 2016-01-28 11:27 ` Suzuki K. Poulose
-1 siblings, 0 replies; 18+ messages in thread
From: Suzuki K. Poulose @ 2016-01-28 11:27 UTC (permalink / raw)
To: Will Deacon, Catalin Marinas
Cc: dann frazier, Duc Dang, Kumar Sankaran, Loc Ho, Feng Kan,
linux-kernel, linux-arm-kernel
On 28/01/16 11:08, Will Deacon wrote:
> On Thu, Jan 28, 2016 at 10:34:41AM +0000, Catalin Marinas wrote:
>> On Wed, Jan 27, 2016 at 04:10:30PM -0700, dann frazier wrote:
>>> 16K page size is an optional feature of the architecture, and is not
>>> supported by the X-Gene SoC family.
This enables support for AppliedMicro X-Gene SOC Family
>>
>> This would be the case on Juno as well. But maybe at some point the
>> X-Gene family would gain a CPU with such support.
>>
>> Anyway, I would rather make 16K pages depend on EXPERT, make it a bit
>> harder to enable. We've had a few questions recently about enabling it
>> on CPUs that don't have such feature.
>
> I thought there was also a suggestion that we could fail gracefully in
> the EFI stub if we detected an unsupported page size?
Yes, there was. But then it was also recommended [1] to add a new stubbed function
for both arm & arm64, where it got lost. May be we should revive it.
https://lkml.org/lkml/2015/10/15/489
Thanks
Suzuki
^ permalink raw reply [flat|nested] 18+ messages in thread
* [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
@ 2016-01-28 11:27 ` Suzuki K. Poulose
0 siblings, 0 replies; 18+ messages in thread
From: Suzuki K. Poulose @ 2016-01-28 11:27 UTC (permalink / raw)
To: linux-arm-kernel
On 28/01/16 11:08, Will Deacon wrote:
> On Thu, Jan 28, 2016 at 10:34:41AM +0000, Catalin Marinas wrote:
>> On Wed, Jan 27, 2016 at 04:10:30PM -0700, dann frazier wrote:
>>> 16K page size is an optional feature of the architecture, and is not
>>> supported by the X-Gene SoC family.
This enables support for AppliedMicro X-Gene SOC Family
>>
>> This would be the case on Juno as well. But maybe at some point the
>> X-Gene family would gain a CPU with such support.
>>
>> Anyway, I would rather make 16K pages depend on EXPERT, make it a bit
>> harder to enable. We've had a few questions recently about enabling it
>> on CPUs that don't have such feature.
>
> I thought there was also a suggestion that we could fail gracefully in
> the EFI stub if we detected an unsupported page size?
Yes, there was. But then it was also recommended [1] to add a new stubbed function
for both arm & arm64, where it got lost. May be we should revive it.
https://lkml.org/lkml/2015/10/15/489
Thanks
Suzuki
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
2016-01-28 11:27 ` Suzuki K. Poulose
@ 2016-01-28 11:30 ` Ard Biesheuvel
-1 siblings, 0 replies; 18+ messages in thread
From: Ard Biesheuvel @ 2016-01-28 11:30 UTC (permalink / raw)
To: Suzuki K. Poulose
Cc: Will Deacon, Catalin Marinas, Feng Kan, dann frazier, Duc Dang,
linux-kernel, Loc Ho, Kumar Sankaran, linux-arm-kernel
On 28 January 2016 at 12:27, Suzuki K. Poulose <Suzuki.Poulose@arm.com> wrote:
> On 28/01/16 11:08, Will Deacon wrote:
>>
>> On Thu, Jan 28, 2016 at 10:34:41AM +0000, Catalin Marinas wrote:
>>>
>>> On Wed, Jan 27, 2016 at 04:10:30PM -0700, dann frazier wrote:
>>>>
>>>> 16K page size is an optional feature of the architecture, and is not
>>>> supported by the X-Gene SoC family.
>
>
> This enables support for AppliedMicro X-Gene SOC Family
>>>
>>>
>>> This would be the case on Juno as well. But maybe at some point the
>>> X-Gene family would gain a CPU with such support.
>>>
>>> Anyway, I would rather make 16K pages depend on EXPERT, make it a bit
>>> harder to enable. We've had a few questions recently about enabling it
>>> on CPUs that don't have such feature.
>>
>>
>> I thought there was also a suggestion that we could fail gracefully in
>> the EFI stub if we detected an unsupported page size?
>
>
> Yes, there was. But then it was also recommended [1] to add a new stubbed
> function
> for both arm & arm64, where it got lost. May be we should revive it.
>
> https://lkml.org/lkml/2015/10/15/489
>
I can pick this up
--
Ard.
^ permalink raw reply [flat|nested] 18+ messages in thread
* [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
@ 2016-01-28 11:30 ` Ard Biesheuvel
0 siblings, 0 replies; 18+ messages in thread
From: Ard Biesheuvel @ 2016-01-28 11:30 UTC (permalink / raw)
To: linux-arm-kernel
On 28 January 2016 at 12:27, Suzuki K. Poulose <Suzuki.Poulose@arm.com> wrote:
> On 28/01/16 11:08, Will Deacon wrote:
>>
>> On Thu, Jan 28, 2016 at 10:34:41AM +0000, Catalin Marinas wrote:
>>>
>>> On Wed, Jan 27, 2016 at 04:10:30PM -0700, dann frazier wrote:
>>>>
>>>> 16K page size is an optional feature of the architecture, and is not
>>>> supported by the X-Gene SoC family.
>
>
> This enables support for AppliedMicro X-Gene SOC Family
>>>
>>>
>>> This would be the case on Juno as well. But maybe at some point the
>>> X-Gene family would gain a CPU with such support.
>>>
>>> Anyway, I would rather make 16K pages depend on EXPERT, make it a bit
>>> harder to enable. We've had a few questions recently about enabling it
>>> on CPUs that don't have such feature.
>>
>>
>> I thought there was also a suggestion that we could fail gracefully in
>> the EFI stub if we detected an unsupported page size?
>
>
> Yes, there was. But then it was also recommended [1] to add a new stubbed
> function
> for both arm & arm64, where it got lost. May be we should revive it.
>
> https://lkml.org/lkml/2015/10/15/489
>
I can pick this up
--
Ard.
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
2016-01-28 11:30 ` Ard Biesheuvel
@ 2016-01-28 11:34 ` Suzuki K. Poulose
-1 siblings, 0 replies; 18+ messages in thread
From: Suzuki K. Poulose @ 2016-01-28 11:34 UTC (permalink / raw)
To: Ard Biesheuvel
Cc: Will Deacon, Catalin Marinas, Feng Kan, dann frazier, Duc Dang,
linux-kernel, Loc Ho, Kumar Sankaran, linux-arm-kernel
On 28/01/16 11:30, Ard Biesheuvel wrote:
> On 28 January 2016 at 12:27, Suzuki K. Poulose <Suzuki.Poulose@arm.com> wrote:
>> On 28/01/16 11:08, Will Deacon wrote:
>>> I thought there was also a suggestion that we could fail gracefully in
>>> the EFI stub if we detected an unsupported page size?
>>
>>
>> Yes, there was. But then it was also recommended [1] to add a new stubbed
>> function
>> for both arm & arm64, where it got lost. May be we should revive it.
>>
>> https://lkml.org/lkml/2015/10/15/489
>>
>
> I can pick this up
>
Thanks Ard.
Cheers
Suzuki
^ permalink raw reply [flat|nested] 18+ messages in thread
* [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
@ 2016-01-28 11:34 ` Suzuki K. Poulose
0 siblings, 0 replies; 18+ messages in thread
From: Suzuki K. Poulose @ 2016-01-28 11:34 UTC (permalink / raw)
To: linux-arm-kernel
On 28/01/16 11:30, Ard Biesheuvel wrote:
> On 28 January 2016 at 12:27, Suzuki K. Poulose <Suzuki.Poulose@arm.com> wrote:
>> On 28/01/16 11:08, Will Deacon wrote:
>>> I thought there was also a suggestion that we could fail gracefully in
>>> the EFI stub if we detected an unsupported page size?
>>
>>
>> Yes, there was. But then it was also recommended [1] to add a new stubbed
>> function
>> for both arm & arm64, where it got lost. May be we should revive it.
>>
>> https://lkml.org/lkml/2015/10/15/489
>>
>
> I can pick this up
>
Thanks Ard.
Cheers
Suzuki
^ permalink raw reply [flat|nested] 18+ messages in thread