On Tue, Feb 18, 2014 at 11:51:58AM -0500, Josh Boyer wrote:
On Tue, Feb 18, 2014 at 04:46:16PM +0000, 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. This can be avoided by building in the code rather
> than leaving it as modules.
Undesirable behavior how? System crashes, random scribblings on kernel
memory, or just a lack of IPMI support?
Random scribblings or crashes are unlikely, and the system will probably
*boot*, but there's a chance of degraded functionality and it's not
necessarily a configuration tested by the vendor. The most likely
outcome is some errors on boot and then things carry on working.
I'm not doubting your conclusions, but I'm curious why this
is a problem
now when we've had the drivers set as modules for 2 years. I can't
recall any major problems.
To an extent it's a correctness issue - the spec says this functionality
should be availble, we should ensure that it's actually available. The
fact that IPMI is only typically present on server systems probably also
limits the feedback we'd get.
--
Matthew Garrett | mjg59(a)srcf.ucam.org