On Wed, Aug 26, 2020 at 11:01:02AM +0200, pet...@infradead.org wrote: > Known broken archs include: Sparc32-SMP, PARISC, ARC-v1-SMP. > There might be a few more, but I've forgotten.
Note that none of those actually have NMIs and llist is mostly OK on those architectures too. The problem is when you combine cmpxchg() with regular stores and llist() doesn't do that. The only architectures that have NMIs are: ARM, ARM64, POWERPC, s390, SH, SPARC64, X86 and XTENSA and all of them have sane atomic ops. (XTENSA is tricky, because it looks like it has parts that don't have sane atomics, but I _think_ those parts also don't have NMI)
