Re: [PATCH v2 2/2] dax: add a sysfs knob to control memmap_on_memory behavior

[Verma, Vishal L]

On Fri, 2023-12-08 at 12:36 +0100, David Hildenbrand wrote:
> On 07.12.23 05:36, Vishal Verma wrote:
[..]
> > 
> > +
> > +What:          /sys/bus/dax/devices/daxX.Y/memmap_on_memory
> > +Date:          October, 2023
> > +KernelVersion: v6.8
> > +Contact:       nvdimm@xxxxxxxxxxxxxxx
> > +Description:
> > +               (RW) Control the memmap_on_memory setting if the dax device
> > +               were to be hotplugged as system memory. This determines whether
> > +               the 'altmap' for the hotplugged memory will be placed on the
> > +               device being hotplugged (memmap_on+memory=1) or if it will be
> > +               placed on regular memory (memmap_on_memory=0). This attribute
> > +               must be set before the device is handed over to the 'kmem'
> > +               driver (i.e.  hotplugged into system-ram).
> > 
> 
> Should we note the dependency on other factors as given in 
> mhp_supports_memmap_on_memory(), especially, the system-wide setting and 
> some weird kernel configurations?
> 
Yep good idea, I'll make a note of those for v3.