On Fri, 19 Dec 2025 18:11:10 +0000
Ben Horgan [off-list ref] wrote:

From: James Morse <james.morse@arm.com>

Now that the MPAM system registers are expected to have values that change,
reprogram them based on the previous value when a CPU is brought online.

Previously MPAM's 'default PARTID' of 0 was always used for MPAM in
kernel-space as this is the PARTID that hardware guarantees to
reset. Because there are a limited number of PARTID, this value is exposed
to user-space, meaning resctrl changes to the resctrl default group would
also affect kernel threads.  Instead, use the task's PARTID value for
kernel work on behalf of user-space too. The default of 0 is kept for both
user-space and kernel-space when MPAM is not enabled.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Ben Horgan <ben.horgan@arm.com>

Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>