On Fri, 2019-06-28 at 17:19 +0530, Anju T Sudhakar wrote: > On 6/28/19 9:04 AM, Qian Cai wrote: > > > > > On Jun 27, 2019, at 11:12 PM, Michael Ellerman <m...@ellerman.id.au> > > > wrote: > > > > > > Qian Cai <c...@lca.pw> writes: > > > > Read of debugfs imc_cmd file for a memory-less node will trigger a crash > > > > below > > > > on this power9 machine which has the following NUMA layout. > > > > > > What type of machine is it? > > > > description: PowerNV > > product: 8335-GTH (ibm,witherspoon) > > vendor: IBM > > width: 64 bits > > capabilities: smp powernv opal > > > Hi Qian Cai, > > Could you please try with this patch: > https://lists.ozlabs.org/pipermail/linuxppc-dev/2019-June/192803.html > > and see if the issue is resolved?
It works fine. Just feel a bit silly that a node without CPU and memory is still online by default during boot at the first place on powerpc, but that is probably a different issue. For example, # numactl -H available: 6 nodes (0,8,252-255) node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 node 0 size: 126801 MB node 0 free: 123199 MB node 8 cpus: 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 node 8 size: 130811 MB node 8 free: 128436 MB node 252 cpus: node 252 size: 0 MB node 252 free: 0 MB node 253 cpus: node 253 size: 0 MB node 253 free: 0 MB node 254 cpus: node 254 size: 0 MB node 254 free: 0 MB node 255 cpus: node 255 size: 0 MB node 255 free: 0 MB node distances: node 0 8 252 253 254 255 0: 10 40 80 80 80 80 8: 40 10 80 80 80 80 252: 80 80 10 80 80 80 253: 80 80 80 10 80 80 254: 80 80 80 80 10 80 255: 80 80 80 80 80 10 # cat /sys/devices/system/node/online 0,8,252-255