From: Palmer Dabbelt > Sent: 03 June 2021 16:39 ... > An example here would be the errata: every system has errata of some > sort, so if we start flipping off various vendor's errata Kconfigs > you'll end up with kernels that only function properly on some systems. > That's fine with me, as long as it's possible to turn on all vendor's > errata Kconfigs at the same time and the resulting kernel functions > correctly on all systems. ISTM that if you can (easily) detect the errata then the detection should be left it - but the kernel fail to boot if the system needs the errata fixed. The same would be needed for DMA in systems with non-coherent memory. Only a hardware engineer would build a system with non-coherent memory and without the ability to do uncached accesses and flush/invalidate small sections of cache. Mind you we did get a dual-cpu system that didn't have cache-coherency between the cpus! That was singularly useless. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
