From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oscar Salvador Date: Tue, 15 Sep 2020 10:31:45 +0000 Subject: Re: [PATCH v3 2/3] mm: don't rely on system state to detect hot-plug operations Message-Id: <20200915103145.GB30015@linux> List-Id: References: <20200915094143.79181-1-ldufour@linux.ibm.com> <20200915094143.79181-3-ldufour@linux.ibm.com> In-Reply-To: <20200915094143.79181-3-ldufour@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Laurent Dufour Cc: akpm@linux-foundation.org, David Hildenbrand , mhocko@suse.com, Greg Kroah-Hartman , linux-mm@kvack.org, "Rafael J . Wysocki" , nathanl@linux.ibm.com, cheloha@linux.ibm.com, Tony Luck , Fenghua Yu , linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org On Tue, Sep 15, 2020 at 11:41:42AM +0200, Laurent Dufour wrote: > [1] According to Oscar Salvador, using this qemu command line, ACPI memory > hotplug operations are raised at SYSTEM_SCHEDULING state: I would like to stress that this is not the only way we can end up hotplugging memor while state = SYSTEM_SCHEDULING. According to David, we can end up doing this if we reboot a VM with hotplugged memory. (And I have seen other virtualization technologies do the same) > Fixes: 4fbce633910e ("mm/memory_hotplug.c: make register_mem_sect_under_node() a callback of walk_memory_range()") > Signed-off-by: Laurent Dufour > Reviewed-by: David Hildenbrand > Cc: stable@vger.kernel.org > Cc: Greg Kroah-Hartman > Cc: "Rafael J. Wysocki" > Cc: Andrew Morton > Cc: Michal Hocko > Cc: Oscar Salvador Reviewed-by: Oscar Salvador -- Oscar Salvador SUSE L3