From: Jianguo Wu <wujianguo@xxxxxxxxxx> From: Jianguo Wu <wujianguo@xxxxxxxxxx> SLUB allocator may cause a BUG_ON() when offlining a memory node if CONFIG_SLUB_DEBUG is on. The scenario is: 1) when creating kmem_cache_node slab, it cause inc_slabs_node() twice. early_kmem_cache_node_alloc ->new_slab ->inc_slabs_node ->inc_slabs_node 2) Later when offlining a memory node, it triggers the BUG_ON() in function slab_mem_offline_callback() due to the extra inc_slabs_node() in function early_kmem_cache_node_alloc(). { if (n) { /* * if n->nr_slabs > 0, slabs still exist on the node * that is going down. We were unable to free them, * and offline_pages() function shouldn't call this * callback. So, we must fail. */ BUG_ON(slabs_node(s, offline_node)); } ------------[ cut here ]------------ kernel BUG at mm/slub.c:3590! invalid opcode: 0000 [#1] SMP CPU 61 Modules linked in: autofs4 sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_filter ip6_tables ipv6 vfat fat dm_mirror dm_region_hash dm_log uinput iTCO_wdt iTCO_vendor_support coretemp hwmon kvm_intel kvm crc32c_intel ghash_clmulni_intel serio_raw pcspkr cdc_ether usbnet mii i2c_i801 i2c_core sg lpc_ich mfd_core shpchp ioatdma i7core_edac edac_core igb dca bnx2 ext4 mbcache jbd2 sr_mod cdrom sd_mod crc_t10dif aesni_intel cryptd aes_x86_64 aes_generic bfa scsi_transport_fc scsi_tgt pata_acpi ata_generic ata_piix megaraid_sas dm_mod [last unloaded: microcode] Pid: 46287, comm: sh Not tainted 3.5.0-rc4-pgtable-00215-g35f0828-dirty #85 IBM System x3850 X5 -[7143O3G]-/Node 1, Processor Card RIP: 0010:[<ffffffff81160b2a>] [<ffffffff81160b2a>] slab_memory_callback+0x1ba/0x1c0 RSP: 0018:ffff880efdcb7c68 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffff880f7ec06100 RCX: 0000000100400001 RDX: 0000000100400002 RSI: ffff880f7ec02000 RDI: ffff880f7ec06100 RBP: ffff880efdcb7c78 R08: ffff88107b6fb098 R09: ffffffff81160a00 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000019 R13: 00000000fffffffb R14: 0000000000000000 R15: ffffffff81abe930 FS: 00007f709f342700(0000) GS:ffff880f7f3a0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000003b5a874570 CR3: 0000000f0da20000 CR4: 00000000000007e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process sh (pid: 46287, threadinfo ffff880efdcb6000, task ffff880f0fa50000) Stack: 0000000000000004 ffff880efdcb7da8 ffff880efdcb7cb8 ffffffff81524af5 0000000000000001 ffffffff81a8b620 ffffffff81a8b640 0000000000000004 ffff880efdcb7da8 00000000ffffffff ffff880efdcb7d08 ffffffff8107a89a Call Trace: [<ffffffff81524af5>] notifier_call_chain+0x55/0x80 [<ffffffff8107a89a>] __blocking_notifier_call_chain+0x5a/0x80 [<ffffffff8107a8d6>] blocking_notifier_call_chain+0x16/0x20 [<ffffffff81352f0b>] memory_notify+0x1b/0x20 [<ffffffff81507104>] offline_pages+0x624/0x700 [<ffffffff811619de>] remove_memory+0x1e/0x20 [<ffffffff813530cc>] memory_block_change_state+0x13c/0x2e0 [<ffffffff81153e96>] ? alloc_pages_current+0xb6/0x120 [<ffffffff81353332>] store_mem_state+0xc2/0xd0 [<ffffffff8133e190>] dev_attr_store+0x20/0x30 [<ffffffff811e2d4f>] sysfs_write_file+0xef/0x170 [<ffffffff81173e28>] vfs_write+0xc8/0x190 [<ffffffff81173ff1>] sys_write+0x51/0x90 [<ffffffff81528d29>] system_call_fastpath+0x16/0x1b Code: 8b 3d cb fd c4 00 be d0 00 00 00 e8 71 de ff ff 48 85 c0 75 9c 48 c7 c7 c0 7f a5 81 e8 c0 89 f1 ff b8 0d 80 00 00 e9 69 fe ff ff <0f> 0b eb fe 66 90 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 RIP [<ffffffff81160b2a>] slab_memory_callback+0x1ba/0x1c0 RSP <ffff880efdcb7c68> ---[ end trace 749e9e9a67c78c12 ]--- Signed-off-by: Jianguo Wu <wujianguo@xxxxxxxxxx> Signed-off-by: Jiang Liu <liuj97@xxxxxxxxx> --- mm/slub.c | 1 - 1 file changed, 1 deletion(-) diff --git a/mm/slub.c b/mm/slub.c index 8c691fa..f8276db 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -2840,7 +2840,6 @@ static void early_kmem_cache_node_alloc(int node) init_tracking(kmem_cache_node, n); #endif init_kmem_cache_node(n); - inc_slabs_node(kmem_cache_node, node, page->objects); add_partial(n, page, DEACTIVATE_TO_HEAD); } -- 1.7.9.5 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>