Excerpts from Anatoly Pugachev's message of September 14, 2020 8:23 pm: > On Mon, Sep 14, 2020 at 10:00 AM Nicholas Piggin <npiggin@xxxxxxxxx> wrote: >> >> Excerpts from Nicholas Piggin's message of September 14, 2020 2:52 pm: >> >> [...] >> >> > The basic fix for sparc64 is to remove its mm_cpumask clearing code. The >> > optimisation could be effectively restored by sending IPIs to mm_cpumask >> > members and having them remove themselves from mm_cpumask. This is more >> > tricky so I leave it as an exercise for someone with a sparc64 SMP. >> > powerpc has a (currently similarly broken) example. >> >> So this compiles and boots on qemu, but qemu does not support any >> sparc64 machines with SMP. Attempting some simple hacks doesn't get >> me far because openbios isn't populating an SMP device tree, which >> blows up everywhere. >> >> The patch is _relatively_ simple, hopefully it shouldn't explode, so >> it's probably ready for testing on real SMP hardware, if someone has >> a few cycles. > > Nick, > > applied this patch to over 'v5.9-rc5' tag , used my test VM (ldom) > with 32 vcpus. > Machine boot, stress-ng test ( run as > "stress-ng --cpu 8 --io 8 --vm 8 --vm-bytes 2G --fork 8 --timeout 15m" ) > finishes without errors. > Thank you very much Anatoly. Thanks, Nick