---------------------------
+What: find_task_by_pid
+When: 2.6.26
+Why: With pid namespaces, calling this funciton will return the
+ wrong task when called from inside a namespace.
+
+ The best way to save a task pid and find a task by this
+ pid later, is to find this task's struct pid pointer (or get
+ it directly from the task) and call pid_task() later.
+
+ If someone really needs to get a task by its pid_t, then
+ he most likely needs the find_task_by_vpid() to get the
+ task from the same namespace as the current task is in, but
+ this may be not so in general.
+
+Who: Pavel Emelyanov <xemul@openvz.org>
+
+---------------------------
+
What: ACPI procfs interface
When: July 2008
Why: ACPI sysfs conversion should be finished by January 2008.
---------------------------
+What: old style serial driver for ColdFire (CONFIG_SERIAL_COLDFIRE)
+When: 2.6.28
+Why: This driver still uses the old interface and has been replaced
+ by CONFIG_SERIAL_MCF.
+Who: Sebastian Siewior <sebastian@breakpoint.cc>
+
+---------------------------
+
What: /sys/o2cb symlink
When: January 2010
Why: /sys/fs/o2cb is the proper location for this information - /sys/o2cb
Why: Implementation became generic; users should now include
linux/semaphore.h instead.
Who: Matthew Wilcox <willy@linux.intel.com>
+
+---------------------------
+
+What: CONFIG_THERMAL_HWMON
+When: January 2009
+Why: This option was introduced just to allow older lm-sensors userspace
+ to keep working over the upgrade to 2.6.26. At the scheduled time of
+ removal fixed lm-sensors (2.x or 3.x) should be readily available.
+Who: Rene Herman <rene.herman@gmail.com>