Commit 0e3cd31f authored by Maciej Wieczor-Retman's avatar Maciej Wieczor-Retman Committed by Borislav Petkov (AMD)
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x86/resctrl: Enable non-contiguous CBMs in Intel CAT



The setting for non-contiguous 1s support in Intel CAT is
hardcoded to false. On these systems, writing non-contiguous
1s into the schemata file will fail before resctrl passes
the value to the hardware.

In Intel CAT CPUID.0x10.1:ECX[3] and CPUID.0x10.2:ECX[3] stopped
being reserved and now carry information about non-contiguous 1s
value support for L3 and L2 cache respectively. The CAT
capacity bitmask (CBM) supports a non-contiguous 1s value if
the bit is set.

The exception are Haswell systems where non-contiguous 1s value
support needs to stay disabled since they can't make use of CPUID
for Cache allocation.

Originally-by: default avatarFenghua Yu <fenghua.yu@intel.com>
Signed-off-by: default avatarMaciej Wieczor-Retman <maciej.wieczor-retman@intel.com>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: default avatarPeter Newman <peternewman@google.com>
Reviewed-by: default avatarReinette Chatre <reinette.chatre@intel.com>
Reviewed-by: default avatarBabu Moger <babu.moger@amd.com>
Tested-by: default avatarPeter Newman <peternewman@google.com>
Link: https://lore.kernel.org/r/1849b487256fe4de40b30f88450cba3d9abc9171.1696934091.git.maciej.wieczor-retman@intel.com
parent 39c6eed1
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