Re: [PATCH v3 2/2] cxl: Add decoders_committed sysfs attribute to cxl_port

[Dan Williams <dan.j.williams@intel.com>]

Jonathan Cameron wrote:
> On Mon, 16 Oct 2023 10:57:54 -0700
> Dave Jiang <dave.jiang@intel.com> wrote:
> 
> > This attribute allows cxl-cli to determine whether there are decoders
> > committed to a memdev.  This is only a snapshot of the state, and
> > doesn't offer any protection or serialization against a concurrent
> > disable-region operation.
> > 
> > Reviewed-by: Jim Harris <jim.harris@samsung.com>
> > Suggested-by: Dan Williams <dan.j.williams@intel.com>
> > Signed-off-by: Dave Jiang <dave.jiang@intel.com>
> Seems reasonable, but it is adding ABI so the docs are missing.
> Documentation/ABI/testing/sysfs-bus-cxl

Agreed, folded in the following:

diff --git a/Documentation/ABI/testing/sysfs-bus-cxl b/Documentation/ABI/testing/sysfs-bus-cxl
index 087f762ebfd5..432610f41aee 100644
--- a/Documentation/ABI/testing/sysfs-bus-cxl
+++ b/Documentation/ABI/testing/sysfs-bus-cxl
@@ -178,6 +178,21 @@ Description:
                hardware decoder target list.
 
 
+What:          /sys/bus/cxl/devices/portX/decoders_committed
+Date:          October, 2023
+KernelVersion: v6.7
+Contact:       linux-cxl@vger.kernel.org
+Description:
+               (RO) A memory device is considered active when any of its
+               decoders are in the "committed" state (See CXL 3.0 8.2.4.19.7
+               CXL HDM Decoder n Control Register). Hotplug and destructive
+               operations like "sanitize" are blocked while device is actively
+               decoding a Host Physical Address range. Note that this number
+               may be elevated without any regionX objects active or even
+               enumerated, as this may be due to decoders established by
+               platform firwmare or a previous kernel (kexec).
+
+
 What:          /sys/bus/cxl/devices/decoderX.Y
 Date:          June, 2021
 KernelVersion: v5.14