summaryrefslogtreecommitdiffstats
path: root/Documentation/ABI/testing/sysfs-class-tee
diff options
context:
space:
mode:
authorTejun Heo <tj@kernel.org>2026-09-14 22:12:34 -1000
committerTejun Heo <tj@kernel.org>2026-09-15 06:57:20 -1000
commita9e3760b0838299649c0d57cca44daaf40ba3c33 (patch)
tree95807ff0e511c05602ef34808cfc660303309057 /Documentation/ABI/testing/sysfs-class-tee
downloadlinux-stable-a9e3760b0838299649c0d57cca44daaf40ba3c33.tar.gz
linux-stable-a9e3760b0838299649c0d57cca44daaf40ba3c33.zip
sched_ext: Maintain an online cid mask in the scheduler arenagrafted
Schedulers on the default cid mapping treat [0, nr_online_cids) as the online set and restart on hotplug. Schedulers that install their own mapping with scx_bpf_cid_override() have no way to learn which cids are online: the count no longer identifies members and the CPU-form cpumask is unusable from cid programs. This is an obvious hole in the cid API. Add scx_bpf_online_cmask(), a kernel-maintained cmask in the scheduler's arena, allocated alongside the per-CPU scratch masks and populated after the cid mapping is finalized and before ops.init(), for child schedulers too. The pointer stays valid through ops.exit() with no reference to take. It is the arena offset as a void pointer, the same form struct_ops arena arguments arrive in. The verifier types the void return as a scalar for the program's arena cast. The mask follows the SCX hotplug notifications: seeded from cpu_active_mask and updated before ops.cid_online/offline() runs, so it lags cpu_online_mask only inside a hotplug transition. Updates walk the scheduler list under the lock that also serializes unlinking. Reads are live, not atomic snapshots. Root initialization excludes hotplug. v2: Reworded the getter kerneldoc (Andrea Righi). Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Andrea Righi <arighi@nvidia.com>
Diffstat (limited to 'Documentation/ABI/testing/sysfs-class-tee')
-rw-r--r--Documentation/ABI/testing/sysfs-class-tee25
1 files changed, 25 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-tee b/Documentation/ABI/testing/sysfs-class-tee
new file mode 100644
index 000000000..1a0a3050a
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-tee
@@ -0,0 +1,25 @@
+What: /sys/class/tee/tee{,priv}X/rpmb_routing_model
+Date: May 2024
+KernelVersion: 6.10
+Contact: op-tee@lists.trustedfirmware.org
+Description:
+ RPMB frames can be routed to the RPMB device via the
+ user-space daemon tee-supplicant or the RPMB subsystem
+ in the kernel. The value "user" means that the driver
+ will route the RPMB frames via user space. Conversely,
+ "kernel" means that the frames are routed via the RPMB
+ subsystem without assistance from tee-supplicant. It
+ should be assumed that RPMB frames are routed via user
+ space if the variable is absent. The primary purpose
+ of this variable is to let systemd know whether
+ tee-supplicant is needed in the early boot with initramfs.
+
+What: /sys/class/tee/tee{,priv}X/revision
+Date: Jan 2026
+KernelVersion: 6.19
+Contact: op-tee@lists.trustedfirmware.org
+Description:
+ Read-only revision string reported by the TEE driver. This is
+ for diagnostics only and must not be used to infer feature
+ support. Use TEE_IOC_VERSION for capability and compatibility
+ checks.