On Fri, Oct 06, 2023 at 04:09:19PM +0100, Julien Grall wrote: > > > On 06/10/2023 15:44, Andrew Cooper wrote: > > From: Alejandro Vallejo <[email protected]> > > > > Adds a new compile-time flag to allow disabling PDX compression and > > compiles out compression-related code/data. It also shorts the pdx<->pfn > > conversion macros and creates stubs for masking functions. > > > > While at it, removes the old arch-defined CONFIG_HAS_PDX flag. Despite the > > illusion of choice, it was not optional. > > > > There are ARM and PPC platforms with sparse RAM banks - leave compression > > active by default there. OTOH, there are no known production x86 systems > > with > > sparse RAM banks, so disable compression. This decision can be revisited if > > such a platform comes along. > > (Process remarks rather than the code itself) > > Jan is away this week so I want to make sure this doesn't go in without him > having a say. > > While I don't particularly care about the approach taken for x86, Jan voiced > concerned with this approach and so far I didn't see any conclusion. If > there is any, then please point me to them. > > For the record, the objections from Jan are in [1]. If we want to ignore > them, then I think we need a vote. Possibly only from the x86 folks (?).
I would be fine in leaving the option to be selected if we knew that such x86 systems might be feasible, but so far we have seen 0 x86 systems with sparse RAM. That said, I don't have a strong opinion, but the hiding on x86 seems fine to me. Interested parties can always forcefully select the option, and a case can be made to make it available again on Kconfig. I'm fine with waiting for Jan, in case he has more to add. Thanks, Roger.
