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charset=UTF-8 Content-Transfer-Encoding: 7bit On 11/21/24 11:30 AM, Guenter Roeck wrote: > On Thu, Nov 21, 2024 at 09:23:28AM -0800, Christoph Lameter (Ampere) wrote: >> On Thu, 21 Nov 2024, Geert Uytterhoeven wrote: >> >>> Linux has supported m68k since last century. >> >> Yeah I fondly remember the 80s where 68K systems were always out of reach >> for me to have. The dream system that I never could get my hands on. The >> creme de la creme du jour. I just had to be content with the 6800 and >> 6502 processors. Then IBM started the sick road down the 8088, 8086 >> that led from crap to more crap. Sigh. >> >>> Any new such assumptions are fixed quickly (at least in the kernel). >>> If you need a specific alignment, make sure to use __aligned and/or >>> appropriate padding in structures. >>> And yes, the compiler knows, and provides __alignof__. >>> >>>> How do you deal with torn reads/writes in such a scenario? Is this UP >>>> only? >>> >>> Linux does not support (rate) SMP m68k machines. >> >> Ah. Ok that explains it. >> >> Do we really need to maintain support for a platform that has been >> obsolete for decade and does not even support SMP? I asked that earlier in this thread too... > Since this keeps coming up, I think there is a much more important > question to ask: > > Do we really need to continue supporting nommu machines ? Is anyone > but me even boot testing those ? Getting rid of nommu would be nice for sure in terms of maintenance, it's one of those things that pop up as a build breaking thing because nobody is using/testing them. I'm all for axing relics from the codebase. Doesn't mean they can't be maintained out-of-tree, but that is where they belong imho. -- Jens Axboe