On Fri, Mar 25, 2022 at 05:54:32PM +0100, Michal Hocko wrote: > > > I thought there are only few pages in the managed by the DMA zone. This > > > is still theoretically possible so I think __GFP_NOWARN makes sense here > > > but it would require to change the patch description. > > > > > > Is this really worth it? > > > > In general I think for kernels where we need the pool and can't allocate > > it, a warning is very useful. We just shouldn't spew it when there is > > no need for the pool to start with. > > Well, do we have any way to find that out during early boot? In general an architecture / configuration that selects CONFIG_ZONE_DMA needs it. We could try to reduce that dependency and/or make it boot time configurable, but there's still plenty of device with sub-32bit addessing limits around, so I'm not sure it would help much.
