Provide mechanism to disable select RDT features & use for Skylake

From: Tony Luck <[email protected]>

Some of the RDT features are affected by errata on Skylake. Make sure unsuspecting users do not accidentally use these.

To do this we add a CPU model quirk mechanism that disables the features affected by the errata by default. But also add a command line mechanism for users to turn them back on again for cases where the use case still works despite the issue.

First patch establishes the CPU quirk mechanism and uses it for the existing Haswell probe code.

Second sets up the command line arguments.

Last adds the code for Skylake model to disable features affected by errata.

Tony Luck (3):
x86/intel_rdt: Move special case code for Haswell to a quirk function x86/intel_rdt: Add command line options for resource director
technology
x86/intel_rdt: Turn off most RDT features on Skylake

 Documentation/admin-guide/kernel-parameters.rst |   1 +
 Documentation/admin-guide/kernel-parameters.txt |   6 +
 arch/x86/kernel/cpu/intel_rdt.c                 | 147 +++++++++++++++++++-----
 3 files changed, 123 insertions(+), 31 deletions(-)

2.11.0