FYI, we noticed the below changes on https://github.com/bbrezillon/linux-0day nand/ecclayout-squashed commit 067c4cc0b9cd92c01c2dbb69f9f24432b79f249a ("mtd: use mtd_ooblayout_xxx() helpers where appropriate") +------------------------------------------+------------+------------+ | | 7ddf922f8b | 067c4cc0b9 | +------------------------------------------+------------+------------+ | boot_successes | 6 | 0 | | boot_failures | 0 | 6 | | BUG:unable_to_handle_kernel | 0 | 6 | | Oops | 0 | 6 | | RIP:nand_transfer_oob | 0 | 6 | | Kernel_panic-not_syncing:Fatal_exception | 0 | 6 | | backtrace:nand_default_bbt | 0 | 6 | | backtrace:ns_init_module | 0 | 6 | | backtrace:kernel_init_freeable | 0 | 6 | +------------------------------------------+------------+------------+ [ 3.610029] sector address bytes: 3 [ 3.610349] options: 0x42 [ 3.611223] Scanning device for bad blocks [ 3.611622] BUG: unable to handle kernel NULL pointer dereference at 0000000000000908 [ 3.612358] IP: [] nand_transfer_oob+0x15/0x82 [ 3.612919] PGD 0 [ 3.613122] Oops: 0000 [#1] SMP [ 3.613446] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.5.0-rc1-00036-g067c4cc #2 [ 3.614121] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014 [ 3.614922] task: ffff880012a88000 ti: ffff880012a90000 task.ti: ffff880012a90000 [ 3.615599] RIP: 0010:[] [] nand_transfer_oob+0x15/0x82 [ 3.616379] RSP: 0000:ffff880012a93cd0 EFLAGS: 00010246 [ 3.616863] RAX: 0000000000000000 RBX: ffff880012a93d70 RCX: 0000000000000010 [ 3.617512] RDX: 0000000000000000 RSI: ffff88000e5f4038 RDI: ffff88000e8e5000 [ 3.618184] RBP: ffff880012a93d20 R08: ffff88000e5f4038 R09: ffff880012a93d70 [ 3.618824] R10: 0000000000000042 R11: 0000000000000000 R12: 0000000000000000 [ 3.619468] R13: 0000000000000000 R14: 0000000000000010 R15: ffff88000e8e5000 [ 3.620114] FS: 0000000000000000(0000) GS:ffff880013600000(0000) knlGS:0000000000000000 [ 3.620838] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3.621359] CR2: 0000000000000908 CR3: 0000000009a17000 CR4: 00000000000406b0 [ 3.622003] Stack: [ 3.622193] ffffffff893f49d3 ffffffff88efd368 0000000000000000 ffff88000e5f4038 [ 3.622905] 0000001000000000 ffff88000e8e5000 0000000000000000 ffff88000e9cc120 [ 3.623624] ffff88000e8e5000 0000000000000000 ffff880012a93d40 ffffffff893d1330 [ 3.624340] Call Trace: [ 3.624569] [] ? nand_read_oob+0x18e/0x276 [ 3.625092] [] ? vprintk_default+0x1d/0x1f [ 3.625612] [] mtd_read_oob+0x32/0x68 [ 3.626095] [] create_bbt+0x10a/0x1f5 [ 3.626574] [] nand_scan_bbt+0x89/0x4b7 [ 3.627074] [] ? _cond_resched+0x27/0x3a [ 3.627578] [] ? kmem_cache_alloc_trace+0x162/0x1ea [ 3.628193] [] nand_default_bbt+0xed/0xf0 [ 3.628707] [] ns_init_module+0x648/0x7f8 [ 3.629225] [] ? inftl_scan_bbt+0x479/0x479 [ 3.629753] [] do_one_initcall+0x1b2/0x1c6 [ 3.630279] [] kernel_init_freeable+0x118/0x19e [ 3.630838] [] ? rest_init+0xc7/0xc7 [ 3.631318] [] kernel_init+0xe/0xd4 [ 3.631785] [] ret_from_fork+0x3f/0x70 [ 3.632278] [] ? rest_init+0xc7/0xc7 [ 3.632751] Code: bf 68 0a 00 00 00 74 0b 55 48 89 e5 e8 4e 59 00 00 5d c3 31 c0 c3 66 66 66 66 90 49 89 d1 48 8b 97 80 01 00 00 49 89 f0 41 8b 01 <48> 8b 92 08 09 00 00 83 f8 01 74 18 72 05 83 f8 02 75 51 41 8b [ 3.635258] RIP [] nand_transfer_oob+0x15/0x82 [ 3.635821] RSP [ 3.636145] CR2: 0000000000000908 [ 3.636454] ---[ end trace 88d0e4c34c271209 ]--- [ 3.636873] Kernel panic - not syncing: Fatal exception Thanks, Ying Huang