Re: [PATCH 1/2] mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE

From: Gregory Price <gourry@gourry.net>
To: "Lorenzo Stoakes (Oracle)" <ljs@kernel.org>
Cc: "David Hildenbrand (Arm)" <david@kernel.org>,
	linux-kernel@vger.kernel.org,
	Catalin Marinas <catalin.marinas@arm.com>,
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Subject: Re: [PATCH 1/2] mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE
Date: Fri, 20 Mar 2026 15:34:24 -0400	[thread overview]
Message-ID: <ab2hQHsCs2MwZqj2@gourry-fedora-PF4VCD3F> (raw)
In-Reply-To: <8ebdbdba-d0b5-4887-98e5-bc45f4565d51@lucifer.local>

On Thu, Mar 19, 2026 at 04:34:04PM +0000, Lorenzo Stoakes (Oracle) wrote:
> On Thu, Mar 19, 2026 at 11:24:27AM -0400, Gregory Price wrote:
> > On Thu, Mar 19, 2026 at 09:19:40AM +0100, David Hildenbrand (Arm) wrote:
> > > All architectures that select CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE also
> > > select CONFIG_ARCH_ENABLE_MEMORY_HOTPLUG. So we can just remove
> > > CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE.
> > >
> > > For CONFIG_MIGRATION, make it depend on CONFIG_MEMORY_HOTREMOVE instead,
> > > and make CONFIG_MEMORY_HOTREMOVE select CONFIG_MIGRATION (just like
> > > CONFIG_CMA and CONFIG_COMPACTION already do).
> > >
> > > We'll clean up CONFIG_MIGRATION next.
> > >
> > > Signed-off-by: David Hildenbrand (Arm) <david@kernel.org>
> >
> > HOTREMOVE has long been a thorn in my side, I appreciate you cleaning
> > this up.
> 
> That is quite the HOTTAKE young Gregory!
> 
> (It seems my pun crimes are continuing)
> 

:P - it's just more config cruft that always catches me cross-platform
when i poke around in dax and hotplug.  It'll be nice to get less
automated reports from CI lol

~Gregory