From 10f78fd0dabbc3856ddd67b09a46abdedb045913 Mon Sep 17 00:00:00 2001 From: Srikar Dronamraju Date: Fri, 27 Nov 2020 11:07:38 +0530 Subject: [PATCH] powerpc/numa: Fix a regression on memoryless node 0 Commit e75130f20b1f ("powerpc/numa: Offline memoryless cpuless node 0") offlines node 0 and expects nodes to be subsequently onlined when CPUs or nodes are detected. Commit 6398eaa26816 ("powerpc/numa: Prefer node id queried from vphn") skips onlining node 0 when CPUs are associated with node 0. On systems with node 0 having CPUs but no memory, this causes node 0 be marked offline. This causes issues at boot time when trying to set memory node for online CPUs while building the zonelist. 0:mon> t [link register ] c000000000400354 __build_all_zonelists+0x164/0x280 [c00000000161bda0] c0000000016533c8 node_states+0x20/0xa0 (unreliable) [c00000000161bdc0] c000000000400384 __build_all_zonelists+0x194/0x280 [c00000000161be30] c000000001041800 build_all_zonelists_init+0x4c/0x118 [c00000000161be80] c0000000004020d0 build_all_zonelists+0x190/0x1b0 [c00000000161bef0] c000000001003cf8 start_kernel+0x18c/0x6a8 [c00000000161bf90] c00000000000adb4 start_here_common+0x1c/0x3e8 0:mon> r R00 = c000000000400354 R16 = 000000000b57a0e8 R01 = c00000000161bda0 R17 = 000000000b57a6b0 R02 = c00000000161ce00 R18 = 000000000b5afee8 R03 = 0000000000000000 R19 = 000000000b6448a0 R04 = 0000000000000000 R20 = fffffffffffffffd R05 = 0000000000000000 R21 = 0000000001400000 R06 = 0000000000000000 R22 = 000000001ec00000 R07 = 0000000000000001 R23 = c000000001175580 R08 = 0000000000000000 R24 = c000000001651ed8 R09 = c0000000017e84d8 R25 = c000000001652480 R10 = 0000000000000000 R26 = c000000001175584 R11 = c000000c7fac0d10 R27 = c0000000019568d0 R12 = c000000000400180 R28 = 0000000000000000 R13 = c000000002200000 R29 = c00000000164dd78 R14 = 000000000b579f78 R30 = 0000000000000000 R15 = 000000000b57a2b8 R31 = c000000001175584 pc = c000000000400194 local_memory_node+0x24/0x80 cfar= c000000000074334 mcount+0xc/0x10 lr = c000000000400354 __build_all_zonelists+0x164/0x280 msr = 8000000002001033 cr = 44002284 ctr = c000000000400180 xer = 0000000000000001 trap = 380 dar = 0000000000001388 dsisr = c00000000161bc90 0:mon> Fix this by setting node to be online while onlining CPUs that belong to node 0. Fixes: e75130f20b1f ("powerpc/numa: Offline memoryless cpuless node 0") Fixes: 6398eaa26816 ("powerpc/numa: Prefer node id queried from vphn") Reported-by: Milan Mohanty Signed-off-by: Srikar Dronamraju Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20201127053738.10085-1-srikar@linux.vnet.ibm.com --- arch/powerpc/mm/numa.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index 63f61d8..f2bf98b 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c @@ -742,8 +742,7 @@ static int __init parse_numa_properties(void) of_node_put(cpu); } - if (likely(nid > 0)) - node_set_online(nid); + node_set_online(nid); } get_n_mem_cells(&n_mem_addr_cells, &n_mem_size_cells); -- 2.7.4