Re: [PATCH] mm/memory-hotplug: Add sysfs hot-remove trigger

[Greg KH <gregkh@linuxfoundation.org>]

On Wed, Feb 06, 2019 at 05:03:53PM +0000, Robin Murphy wrote:
> ARCH_MEMORY_PROBE is a useful thing for testing and debugging hotplug,
> but being able to exercise the (arguably trickier) hot-remove path would
> be even more useful. Extend the feature to allow removal of offline
> sections to be triggered manually to aid development.
> 
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
> 
> This is inspired by a previous proposal[1], but in coming up with a
> more robust interface I ended up rewriting the whole thing from
> scratch. The lack of documentation is semi-deliberate, since I don't
> like the idea of anyone actually relying on this interface as ABI, but
> as a handy tool it felt useful enough to be worth sharing :)
> 
> Robin.
> 
> [1] https://lore.kernel.org/lkml/22d34fe30df0fbacbfceeb47e20cb1184af73585.1511433386.git.ar@linux.vnet.ibm.com/
> 
>  drivers/base/memory.c | 42 +++++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 41 insertions(+), 1 deletion(-)

You have to add new Documentation/ABI entries for each new sysfs file
you add :(