FYI, we noticed the below changes on git://git.infradead.org/users/kbusch/linux-nvme master commit bf5c2e3e82b9dd957c4aedb6fa4dabf3e7bec8a3 ("blk-mq: dynamic h/w context count") +-----------------------------------------------+------------+------------+ | | 1fe4f3f9b7 | bf5c2e3e82 | +-----------------------------------------------+------------+------------+ | boot_successes | 8 | 0 | | boot_failures | 0 | 6 | | BUG_kmalloc-#(Not_tainted):Poison_overwritten | 0 | 6 | | INFO:#-#.First_byte#instead_of | 0 | 6 | | INFO:Slab#objects=#used=#fp=0x(null)flags= | 0 | 6 | | INFO:Object#@offset=#fp= | 0 | 6 | | backtrace:init | 0 | 6 | | backtrace:kernel_init_freeable | 0 | 6 | +-----------------------------------------------+------------+------------+ [ 5.397219] brd: module loaded [ 5.428701] loop: module loaded [ 7.750179] ============================================================================= [ 7.751886] BUG kmalloc-512 (Not tainted): Poison overwritten [ 7.752927] ----------------------------------------------------------------------------- [ 7.752927] [ 7.755116] Disabling lock debugging due to kernel taint [ 7.756105] INFO: 0xffff88000d0e6760-0xffff88000d0e694f. First byte 0x0 instead of 0x6b [ 7.757747] INFO: Slab 0xffffea0000343900 objects=19 used=19 fp=0x (null) flags=0x100000000004080 [ 7.759558] INFO: Object 0xffff88000d0e6760 @offset=10080 fp=0xffff88000d0e6418 [ 7.759558] [ 7.761653] Bytes b4 ffff88000d0e6750: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.763451] Object ffff88000d0e6760: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.765235] Object ffff88000d0e6770: 21 43 65 87 00 00 00 00 00 00 00 00 00 00 00 00 !Ce............. [ 7.767018] Object ffff88000d0e6780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.768797] Object ffff88000d0e6790: 00 00 00 00 00 00 00 00 21 43 65 87 00 00 00 00 ........!Ce..... [ 7.770578] Object ffff88000d0e67a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.772366] Object ffff88000d0e67b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.774154] Object ffff88000d0e67c0: 21 43 65 87 00 00 00 00 00 00 00 00 00 00 00 00 !Ce............. [ 7.775927] Object ffff88000d0e67d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.777709] Object ffff88000d0e67e0: 00 00 00 00 00 00 00 00 21 43 65 87 00 00 00 00 ........!Ce..... [ 7.779492] Object ffff88000d0e67f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.781271] Object ffff88000d0e6800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.783055] Object ffff88000d0e6810: 21 43 65 87 00 00 00 00 00 00 00 00 00 00 00 00 !Ce............. [ 7.784834] Object ffff88000d0e6820: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.786623] Object ffff88000d0e6830: 00 00 00 00 00 00 00 00 21 43 65 87 00 00 00 00 ........!Ce..... [ 7.788405] Object ffff88000d0e6840: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.790187] Object ffff88000d0e6850: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.791963] Object ffff88000d0e6860: 21 43 65 87 00 00 00 00 00 00 00 00 00 00 00 00 !Ce............. [ 7.793736] Object ffff88000d0e6870: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.795518] Object ffff88000d0e6880: 00 00 00 00 00 00 00 00 21 43 65 87 00 00 00 00 ........!Ce..... [ 7.797312] Object ffff88000d0e6890: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.799092] Object ffff88000d0e68a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.800859] Object ffff88000d0e68b0: 21 43 65 87 00 00 00 00 00 00 00 00 00 00 00 00 !Ce............. [ 7.803045] Object ffff88000d0e68c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.804885] Object ffff88000d0e68d0: 00 00 00 00 00 00 00 00 21 43 65 87 00 00 00 00 ........!Ce..... [ 7.806673] Object ffff88000d0e68e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.808462] Object ffff88000d0e68f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.810247] Object ffff88000d0e6900: 21 43 65 87 00 00 00 00 00 00 00 00 00 00 00 00 !Ce............. [ 7.812024] Object ffff88000d0e6910: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.813802] Object ffff88000d0e6920: 00 00 00 00 00 00 00 00 21 43 65 87 00 00 00 00 ........!Ce..... [ 7.815581] Object ffff88000d0e6930: 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.817361] Object ffff88000d0e6940: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 7.819156] Object ffff88000d0e6950: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5 kkkkkkkkkkkkkkk. [ 7.820933] Redzone ffff88000d0e6960: bb bb bb bb bb bb bb bb ........ [ 7.822646] Padding ffff88000d0e6aa0: 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZ [ 7.824368] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G B 4.4.0-rc8-00134-gbf5c2e3 #1 [ 7.826099] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014 [ 7.827832] 0000000000000000 ffff88001209f7f0 ffffffff8150590a ffff880012802b40 [ 7.829658] ffff88001209f820 ffffffff811c0f5f ffff88000d0e6760 000000000000006b [ 7.831483] ffff880012802b40 ffff88000d0e694f ffff88001209f878 ffffffff811c100a [ 7.833306] Call Trace: [ 7.833997] [] dump_stack+0x4b/0x63 [ 7.834968] [] print_trailer+0x127/0x130 [ 7.835986] [] check_bytes_and_report+0xa2/0xea [ 7.837066] [] check_object+0x10a/0x1f7 [ 7.838073] [] ? efi_partition+0xd0/0x523 [ 7.839092] [] alloc_debug_processing+0xdc/0x14b [ 7.840179] [] ___slab_alloc+0x485/0x612 [ 7.841193] [] ? efi_partition+0xd0/0x523 [ 7.842225] [] ? __lock_is_held+0x3c/0x57 [ 7.843244] [] ? __lock_is_held+0x3c/0x57 [ 7.844267] [] ? efi_partition+0xd0/0x523 [ 7.845289] [] __slab_alloc+0x4f/0x83 [ 7.846277] [] ? __slab_alloc+0x4f/0x83 [ 7.847279] [] ? efi_partition+0xd0/0x523 [ 7.848302] [] ? efi_partition+0xd0/0x523 [ 7.849324] [] kmem_cache_alloc_trace+0x88/0x209 [ 7.850414] [] efi_partition+0xd0/0x523 [ 7.851422] [] ? vsnprintf+0x89/0x3af [ 7.852406] [] ? snprintf+0x36/0x3e [ 7.853377] [] check_partition+0x11c/0x1b2 [ 7.854411] [] ? check_partition+0x11c/0x1b2 [ 7.855467] [] rescan_partitions+0x7c/0x252 [ 7.856513] [] ? mutex_unlock+0xe/0x10 [ 7.857509] [] __blkdev_get+0x1c4/0x3dc [ 7.858513] [] blkdev_get+0x1c6/0x2fd [ 7.859501] [] add_disk+0x42d/0x456 [ 7.860470] [] ? revalidate_disk+0x78/0x84 [ 7.861503] [] ? vp_get+0x57/0x67 [ 7.862454] [] virtblk_probe+0x560/0x641 [ 7.863472] [] virtio_dev_probe+0x111/0x187 [ 7.864512] [] driver_probe_device+0xf7/0x250 [ 7.865582] [] __driver_attach+0x61/0x83 [ 7.866599] [] ? driver_probe_device+0x250/0x250 [ 7.867686] [] bus_for_each_dev+0x6f/0x87 [ 7.868711] [] driver_attach+0x1e/0x20 [ 7.869710] [] bus_add_driver+0xf2/0x1e4 [ 7.880475] [] ? init_cryptoloop+0x28/0x28 [ 7.881509] [] driver_register+0x8a/0xc6 [ 7.882530] [] ? init_cryptoloop+0x28/0x28 [ 7.883560] [] register_virtio_driver+0x2b/0x2d [ 7.884637] [] init+0x5a/0x87 [ 7.885552] [] do_one_initcall+0xe7/0x177 [ 7.886580] [] kernel_init_freeable+0x1c2/0x24a [ 7.887663] [] ? rest_init+0x140/0x140 [ 7.888658] [] kernel_init+0xe/0xd4 [ 7.889630] [] ret_from_fork+0x3f/0x70 [ 7.890631] [] ? rest_init+0x140/0x140 [ 7.891635] FIX kmalloc-512: Restoring 0xffff88000d0e6760-0xffff88000d0e694f=0x6b [ 7.891635] [ 7.893751] FIX kmalloc-512: Marking all objects used Thanks, Kernel Test Robot