Greetings, 0day kernel testing robot got the below dmesg and the first bad commit is https://github.com/l1k/linux revpi_staging commit b215eb0a1dbd1c683ee151371b9626e5c923610c Author: Lukas Wunner <lukas(a)wunner.de&gt; AuthorDate: Mon Nov 26 11:11:34 2018 +0100 Commit: Lukas Wunner <lukas(a)wunner.de&gt; CommitDate: Wed Jun 12 20:35:30 2019 +0200 spi: Guarantee cacheline alignment of driver-private data __spi_alloc_controller() uses a single allocation to accommodate struct spi_controller and the driver-private data, but places the latter behind the former. This order does not guarantee cacheline alignment of the driver-private data. It does guarantee cacheline alignment of struct spi_controller but the structure doesn't make any use of that property. Reverse the order. A forthcoming commit leverages this to grant DMA access to driver-private data of the BCM2835 SPI master. Signed-off-by: Lukas Wunner <lukas(a)wunner.de&gt; a57c4dae11 dmaengine: bcm2835: Allow cyclic transactions without interrupt b215eb0a1d spi: Guarantee cacheline alignment of driver-private data 28c6177476 spi: bcm2835: Speed up RX-only DMA transfers by zero-filling TX FIFO +-------------------------------------------------+------------+------------+------------+ | | a57c4dae11 | b215eb0a1d | 28c6177476 | +-------------------------------------------------+------------+------------+------------+ | boot_successes | 28 | 0 | 0 | | boot_failures | 1 | 14 | 11 | | BUG:kernel_reboot-without-warning_in_test_stage | 1 | | | | kernel_BUG_at_mm/slab.c | 0 | 14 | 11 | | invalid_opcode:#[##] | 0 | 14 | 11 | | RIP:___cache_free | 0 | 14 | 11 | | Kernel_panic-not_syncing:Fatal_exception | 0 | 14 | 11 | +-------------------------------------------------+------------+------------+------------+ If you fix the issue, kindly add following tag Reported-by: kernel test robot <lkp(a)intel.com&gt; [ 14.548037] Creating 1 MTD partitions on "NAND 128MiB 1,8V 8-bit": [ 14.550120] 0x000000000000-0x000008000000 : "NAND simulator partition 0" [ 14.560934] ftl_cs: FTL header not found. [ 14.563402] parport0: cannot grant exclusive access for device spi-lm70llp [ 14.564666] ------------[ cut here ]------------ [ 14.565591] kernel BUG at mm/slab.c:2743! [ 14.566685] invalid opcode: 0000 [#1] PREEMPT SMP PTI [ 14.567611] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.2.0-rc4-00054-gb215eb0 #1 [ 14.569330] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 [ 14.570919] RIP: 0010:___cache_free+0x247/0x590 [ 14.571758] Code: 0f b6 4e 1c 48 c1 ee 20 29 f0 d3 e8 41 0f b6 4e 1d 01 f0 d3 e8 41 3b 46 24 72 02 0f 0b 41 0f af 46 14 48 01 d0 48 39 c3 74 02 <0f> 0b 41 f6 46 21 08 74 24 49 63 8e e0 00 00 00 4d 63 7e 74 be 6b [ 14.571758] RSP: 0000:ffff88801e5b3c40 EFLAGS: 00010006 [ 14.571758] RAX: ffff88801a39d000 RBX: ffff88801a39d150 RCX: 000000000000000b [ 14.571758] RDX: ffff88801a39d000 RSI: 0000000000000000 RDI: 0000000080000000 [ 14.571758] RBP: ffff88801e5b3ca8 R08: ffffea00005bca58 R09: 0000000000000000 [ 14.571758] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88801ec00000 [ 14.571758] R13: 00000000001f21a0 R14: ffff88801e400900 R15: ffffffff81d127e5 [ 14.571758] FS: 0000000000000000(0000) GS:ffff88801ec00000(0000) knlGS:0000000000000000 [ 14.571758] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 14.571758] CR2: 00000000ffffffff CR3: 0000000003212001 CR4: 00000000001606e0 [ 14.571758] Call Trace: [ 14.571758] ? __virt_addr_valid+0xf6/0x110 [ 14.571758] kfree+0x165/0x190 [ 14.601265] ? spi_controller_messages_show+0x30/0x30 [ 14.601265] spi_controller_release+0x15/0x20 [ 14.601265] device_release+0x77/0xc0 [ 14.601265] ? dev_attr_show+0x70/0x70 [ 14.601265] kobject_put+0x1c6/0x220 [ 14.601265] put_device+0x1f/0x30 [ 14.601265] spi_lm70llp_attach+0x2e6/0x330 [ 14.601265] ? driver_detach+0x40/0x40 [ 14.601265] port_check+0x2f/0x40 [ 14.601265] bus_for_each_dev+0x99/0x100 [ 14.601265] __parport_register_driver+0x8f/0x170 [ 14.601265] init_spi_lm70llp+0x26/0x4a [ 14.601265] ? fsl_spi_init+0x43/0x43 [ 14.601265] do_one_initcall+0x2bc/0x67c [ 14.601265] ? debug_smp_processor_id+0x114/0x120 [ 14.601265] kernel_init_freeable+0x608/0x767 [ 14.601265] ? rest_init+0x290/0x290 [ 14.601265] kernel_init+0x13/0x170 [ 14.601265] ? schedule_tail+0x7d/0x80 [ 14.601265] ? rest_init+0x290/0x290 [ 14.601265] ret_from_fork+0x3a/0x50 [ 14.601265] ---[ end trace f117052f33543e25 ]--- [ 14.601265] RIP: 0010:___cache_free+0x247/0x590 # HH:MM RESULT GOOD BAD GOOD_BUT_DIRTY DIRTY_NOT_BAD git bisect start f76b6a20b72a0691b6885fada0fe7799db107640 d1fdb6d8f6a4109a4263176c84b899076a5f8008 -- git bisect bad e43340ab362c58bd222a9bd157be61a2defea681 # 00:38 B 0 2 21 5 Merge 'kbuild/build-test' into devel-hourly-2019061511 git bisect good cdb414a8ee60171ec718409c3bf1b3aee59ed73c # 01:02 G 10 0 9 9 Merge 'spi/for-5.2' into devel-hourly-2019061511 git bisect good 43ffc71121f53e4e7b75acb2ef168135007b365c # 01:24 G 11 0 4 4 Merge 'tip/x86/cache' into devel-hourly-2019061511 git bisect good caf1ce79d489161b53f242d613e602594e613663 # 01:40 G 11 0 8 8 Merge 'ntb/ntb' into devel-hourly-2019061511 git bisect good def2269fa02d436cb604ce1fc8d94c0d38b6036c # 02:10 G 11 0 3 3 Merge 'yhuang/autonuma6' into devel-hourly-2019061511 git bisect good 64db7d9b2c09db68c5b1be808e87cfc01d9c2aba # 03:10 G 10 0 7 8 Merge 'stblinux/maintainers/next' into devel-hourly-2019061511 git bisect good c7084246d84aef0c6ce01e4751a7f724c5d01c62 # 03:20 G 10 0 7 7 Merge 'pza/hantro/imx8m-v5' into devel-hourly-2019061511 git bisect bad 7b9a56fe350068075ffda973f1c4a4405fc3ba34 # 03:30 B 0 9 25 2 Merge 'char-misc/char-misc-next' into devel-hourly-2019061511 git bisect bad 39bd443109587775bcd872686caed5b4c0f10dfe # 04:20 B 0 11 27 1 Merge 'l1k/revpi_staging' into devel-hourly-2019061511 git bisect bad b215eb0a1dbd1c683ee151371b9626e5c923610c # 04:48 B 0 2 22 6 spi: Guarantee cacheline alignment of driver-private data git bisect good c21fc68c5c6b45a2d0b4e7d4645b4af6c810abf6 # 05:17 G 10 0 1 1 Merge remote-tracking branch 'spi/topic/pump-rt' into spi-next git bisect good a57c4dae1179bbba2be84c2a4a3fc8cf4301eed8 # 05:32 G 11 0 2 3 dmaengine: bcm2835: Allow cyclic transactions without interrupt # first bad commit: [b215eb0a1dbd1c683ee151371b9626e5c923610c] spi: Guarantee cacheline alignment of driver-private data git bisect good a57c4dae1179bbba2be84c2a4a3fc8cf4301eed8 # 05:37 G 30 0 6 9 dmaengine: bcm2835: Allow cyclic transactions without interrupt # extra tests with debug options git bisect bad b215eb0a1dbd1c683ee151371b9626e5c923610c # 05:50 B 0 7 25 4 spi: Guarantee cacheline alignment of driver-private data # extra tests on HEAD of linux-devel/devel-hourly-2019061511 git bisect bad f76b6a20b72a0691b6885fada0fe7799db107640 # 05:50 B 0 328 345 0 0day head guard for 'devel-hourly-2019061511' # extra tests on tree/branch l1k/revpi_staging git bisect bad 28c61774769c4652df0bb21072a7bb3610321049 # 06:01 B 0 5 19 0 spi: bcm2835: Speed up RX-only DMA transfers by zero-filling TX FIFO # extra tests with first bad commit reverted git bisect good 99cd9b0bc5407567194122871747e0d946f05562 # 06:29 G 10 0 2 2 Revert "spi: Guarantee cacheline alignment of driver-private data" --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/lkp Intel Corporation