Re: [PATCH V2] Change ACPI IPMI support to "default y"

From: Rafael J. Wysocki
Date: Thu Feb 20 2014 - 18:55:40 EST


On Thursday, February 20, 2014 02:14:58 PM Russ Anderson wrote:
> On Tue, Feb 18, 2014 at 11:28:29AM -0500, Matthew Garrett wrote:
> > The ACPI IPMI driver implements IPMI operation region support for the ACPI
> > core. Systems that declare ACPI operation regions may reference them at any
> > time, including during kernel initialisation. These accesses will fail
> > unless the ACPI IPMI driver is present, and undesirable system behaviour
> > may result. Set the default to Y in order to encourage distributions and
> > users to configure kernels to avoid awkward surprises.
>
> No, please do not build the ipmi_si driver into the kernel.
> Not all systems want, or need, the ipmi_si driver.
>
> The distro that added this change created all sorts of support
> problems.

Which distro was that?

Do you have any pointers to specific bug reports related to that?

Rafael


> Problems include kipmi0 spinning at 100% of cpu
> (creating a performance hit) and long boot delays (as the
> kernel tries to talk to a BMC that will never respond).
> It has been a big mess.
>
> Nacked-by: Russ Anderson <rja@xxxxxxx>
>
>
> > Signed-off-by: Matthew Garrett <matthew.garrett@xxxxxxxxxx>
> > ---
> > Actually, I guess we also want this on CONFIG_IPMI_HANDLER for least
> > surprise
> >
> > drivers/acpi/Kconfig | 2 +-
> > drivers/char/ipmi/Kconfig | 2 ++
> > 2 files changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
> > index 4770de5..0e6aab9 100644
> > --- a/drivers/acpi/Kconfig
> > +++ b/drivers/acpi/Kconfig
> > @@ -162,7 +162,7 @@ config ACPI_PROCESSOR
> > config ACPI_IPMI
> > tristate "IPMI"
> > depends on IPMI_SI
> > - default n
> > + default y
> > help
> > This driver enables the ACPI to access the BMC controller. And it
> > uses the IPMI request/response message to communicate with BMC
> > diff --git a/drivers/char/ipmi/Kconfig b/drivers/char/ipmi/Kconfig
> > index 0baa8fa..eea8464 100644
> > --- a/drivers/char/ipmi/Kconfig
> > +++ b/drivers/char/ipmi/Kconfig
> > @@ -5,6 +5,7 @@
> > menuconfig IPMI_HANDLER
> > tristate 'IPMI top-level message handler'
> > depends on HAS_IOMEM
> > + default y if ACPI
> > help
> > This enables the central IPMI message handler, required for IPMI
> > to work.
> > @@ -45,6 +46,7 @@ config IPMI_DEVICE_INTERFACE
> >
> > config IPMI_SI
> > tristate 'IPMI System Interface handler'
> > + default y if ACPI
> > help
> > Provides a driver for System Interfaces (KCS, SMIC, BT).
> > Currently, only KCS and SMIC are supported. If
>
>

--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/