On Thu, Nov 10, 2016 at 04:57:19PM +0900, Sergey Senozhatsky wrote: > Hello Paul, > > x86_64, linux-next 20161110 > > WARN_ON_ONCE(!(special & RCU_DYNTICK_CTRL_CTR)); > > [ 0.436242] ------------[ cut here ]------------ > [ 0.436307] WARNING: CPU: 3 PID: 0 at kernel/rcu/tree.c:380 rcu_momentary_dyntick_idle+0xa7/0xb8 > [ 0.436381] Modules linked in: > [ 0.436437] CPU: 3 PID: 0 Comm: swapper/3 Not tainted 4.9.0-rc4-next-20161110-dbg-00001-g0d7df5d-dirty #863 > [ 0.436513] Hardware name: SAMSUNG ELECTRONICS CO.,LTD Samsung DeskTop System/Samsung DeskTop System, BIOS 05CC 04/09/2010 > [ 0.436595] Call Trace: > [ 0.436651] dump_stack+0x4d/0x63 > [ 0.436706] __warn+0xb8/0xd3 > [ 0.436760] warn_slowpath_null+0x18/0x1a > [ 0.436815] rcu_momentary_dyntick_idle+0xa7/0xb8 > [ 0.436872] rcu_note_context_switch+0x2c8/0x2d5 > [ 0.436930] __schedule+0x62/0x3b6 > [ 0.436984] schedule+0x84/0x95 > [ 0.437038] schedule_preempt_disabled+0x10/0x19 > [ 0.437095] cpu_startup_entry+0x18c/0x191 > [ 0.437152] start_secondary+0xef/0xf2 > [ 0.437207] start_cpu+0x5/0x14 > [ 0.437263] ---[ end trace c0bbb435a1f86b8a ]--- > > > > WARN_ON_ONCE(!(atomic_read(&rdtp->dynticks) & 0x1)); > > [ 0.895911] ------------[ cut here ]------------ > [ 0.895966] WARNING: CPU: 0 PID: 1 at kernel/rcu/tree.c:1116 rcu_nmi_exit+0x63/0x82 > [ 0.896026] Modules linked in:^Ac > [ 0.896078] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 4.9.0-rc4-next-20161110-dbg-00001-g0d7df5d-dirty #863 > [ 0.896157] Hardware name: SAMSUNG ELECTRONICS CO.,LTD Samsung DeskTop System/Samsung DeskTop System, BIOS 05CC 04/09/2010 > [ 0.896236] Call Trace: > [ 0.896287] <NMI> > [ 0.896338] dump_stack+0x4d/0x63 > [ 0.896390] __warn+0xb8/0xd3 > [ 0.896442] warn_slowpath_null+0x18/0x1a > [ 0.896495] rcu_nmi_exit+0x63/0x82 > [ 0.896548] do_nmi+0x2b4/0x31f > [ 0.896600] end_repeat_nmi+0x1a/0x1e > [ 0.896652] RIP: 0010:ioread32+0xb/0x2f > [ 0.896705] RSP: 0000:ffffc900000176c0 EFLAGS: 00000296^Ac > [ 0.896762] RAX: 0000000000000004 RBX: ffff880132868a80 RCX: 0000000000000000 > [ 0.896820] RDX: 0000000000000003 RSI: ffffc9000100e180 RDI: ffffc9000100e180 > [ 0.896879] RBP: ffffc900000176c8 R08: 000000000000000a R09: 000000000000b885 > [ 0.896938] R10: ffffc900000178e8 R11: ffff8801330b0080 R12: 00000000fffb6f2e > [ 0.896996] R13: 0000000000000006 R14: 000000000000005b R15: ffff88013288f848 > [ 0.897055] ? ioread32+0xb/0x2f > [ 0.897107] ? ioread32+0xb/0x2f > [ 0.897160] <EOE> > [ 0.897210] ? nv50_i2c_bus_sense_scl+0x1f/0x24 > [ 0.897265] nvkm_i2c_bus_getscl+0xa/0xc > [ 0.897318] sclhi+0x36/0x6a > [ 0.897369] i2c_outb+0x49/0xcf > [ 0.897422] try_address+0x30/0x6f > [ 0.897475] bit_xfer+0x23a/0x402 > [ 0.897527] __i2c_transfer+0x156/0x18b > [ 0.897581] i2c_transfer+0x6e/0x8c > [ 0.897634] ? nvkm_fantog_create+0xcd/0xcd > [ 0.897688] nvkm_i2c_bus_probe+0x141/0x200 > [ 0.897741] ? extdev_table+0xa7/0xc6 > [ 0.897793] nvkm_therm_ic_ctor+0x141/0x14f > [ 0.897847] ? nvkm_therm_ic_ctor+0x141/0x14f > [ 0.897900] ? nvbios_rd08+0x1a/0x30 > [ 0.897953] ? nvbios_therm_sensor_parse+0x97/0x1ca > [ 0.898008] nvkm_therm_oneinit+0x19/0x3b > [ 0.898061] nvkm_subdev_init+0x89/0x195 > [ 0.898114] nvkm_device_init+0x145/0x204 > [ 0.898167] nvkm_udevice_init+0x2f/0x4a > [ 0.898220] nvkm_object_init+0x71/0x15d > [ 0.898273] nvkm_ioctl_new+0x1aa/0x27a > [ 0.898326] ? nvkm_client_notify+0x22/0x22 > [ 0.898380] ? nvkm_udevice_rd08+0x1f/0x1f > [ 0.898434] nvkm_ioctl+0x174/0x1d0 > [ 0.898487] nvkm_client_ioctl+0xd/0xf > [ 0.898540] nvif_object_ioctl+0x42/0x44 > [ 0.898594] nvif_object_init+0xc4/0x104 > [ 0.898647] nvif_device_init+0xd/0x2b > [ 0.898700] nouveau_drm_load+0x269/0x89e > [ 0.898753] drm_dev_register+0x7f/0xc0 > [ 0.898806] drm_get_pci_dev+0xf3/0x1bd > [ 0.898860] nouveau_drm_probe+0x1a2/0x1c1 > [ 0.898913] pci_device_probe+0x7e/0xe6 > [ 0.898966] driver_probe_device+0x130/0x284 > [ 0.899020] __driver_attach+0x6a/0x8c > [ 0.899074] ? driver_probe_device+0x284/0x284 > [ 0.899128] bus_for_each_dev+0x68/0x80 > [ 0.899181] driver_attach+0x19/0x1b > [ 0.899234] bus_add_driver+0xe9/0x1d9 > [ 0.899287] driver_register+0x83/0xba > [ 0.899340] ? ttm_init+0x5d/0x5d > [ 0.899393] __pci_register_driver+0x47/0x49 > [ 0.899446] drm_pci_init+0x47/0xc8 > [ 0.899500] ? ttm_init+0x5d/0x5d > [ 0.899552] ? set_debug_rodata+0x12/0x12 > [ 0.899605] nouveau_drm_init+0x1db/0x1dd > [ 0.899658] do_one_initcall+0x8b/0x10e > [ 0.899711] ? set_debug_rodata+0x12/0x12 > [ 0.899765] kernel_init_freeable+0x123/0x1ab > [ 0.899819] ? rest_init+0x7d/0x7d > [ 0.899871] kernel_init+0x9/0xeb > [ 0.899924] ret_from_fork+0x22/0x30 > [ 0.899977] ---[ end trace c0bbb435a1f86b8b ]--- Hello, Sergey, Should be fixed by 0ea13930e9a8 ("rcu: Maintain special bits at bottom of ->dynticks counter"), which should be in -next today. And thank you for your testing efforts! Thanx, Paul -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html