FYI, we noticed the below changes on
https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git wb-buf-throttle
commit 1131f64d74958d495d8a6d5f9b981e86ed3beb7a ("blk-mq: don't throttle for virtual devices")
+------------------------------------------+------------+------------+
| | f21fb0e42c | 1131f64d74 |
+------------------------------------------+------------+------------+
| boot_successes | 6 | 0 |
| boot_failures | 0 | 6 |
| BUG:unable_to_handle_kernel | 0 | 6 |
| Oops | 0 | 6 |
| RIP:blk_wb_wait | 0 | 6 |
| Kernel_panic-not_syncing:Fatal_exception | 0 | 6 |
| backtrace:init | 0 | 6 |
| backtrace:kernel_init_freeable | 0 | 6 |
+------------------------------------------+------------+------------+
[ 8.897469] FDC 0 is a S82078B
[ 8.984074] brd: module loaded
[ 9.030737] loop: module loaded
[ 9.045718] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
[ 9.048069] IP: [<ffffffff815336b0>] blk_wb_wait+0x5/0x174
[ 9.049489] PGD 0
[ 9.050433] Oops: 0000 [#1] SMP
[ 9.051614] Modules linked in:
[ 9.052686] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.6.0-rc1-00028-g1131f64 #1
[ 9.054734] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014
[ 9.056997] task: ffff880012028040 ti: ffff880012024000 task.ti: ffff880012024000
[ 9.059068] RIP: 0010:[<ffffffff815336b0>] [<ffffffff815336b0>] blk_wb_wait+0x5/0x174
[ 9.061281] RSP: 0018:ffff8800120277b8 EFLAGS: 00010246
[ 9.062563] RAX: 0000000000000000 RBX: ffff88000cb7ca40 RCX: 0000000000000000
[ 9.064103] RDX: 0000000000000000 RSI: ffff88000cb7ca40 RDI: 0000000000000000
[ 9.065585] RBP: ffff880012027820 R08: 0000000000000000 R09: 0000000000000004
[ 9.067127] R10: ffffea0000313940 R11: 0000000000000000 R12: ffff88000c418008
[ 9.068670] R13: ffff880012028040 R14: 00000000ffffffff R15: ffff880012028040
[ 9.070208] FS: 0000000000000000(0000) GS:ffff880013400000(0000) knlGS:0000000000000000
[ 9.072425] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 9.074277] CR2: 0000000000000008 CR3: 0000000002418000 CR4: 00000000000406f0
[ 9.076404] Stack:
[ 9.077575] ffffffff81531a08 ffff880012028040 0000000000000000 0000000081525471
[ 9.080881] ffff88000cb7ca40 0000000012028040 ffff8800120277f8 ffffffff81191334
[ 9.084175] ffff88000cb7ca40 ffff88000c418008 ffff880012028040 00000000ffffffff
[ 9.087492] Call Trace:
[ 9.088746] [<ffffffff81531a08>] ? blk_sq_make_request+0x96/0x543
[ 9.090753] [<ffffffff81191334>] ? mempool_alloc_slab+0x1f/0x21
[ 9.092681] [<ffffffff81525733>] generic_make_request+0xbd/0x15b
[ 9.094606] [<ffffffff815258da>] submit_bio+0x109/0x114
[ 9.096410] [<ffffffff8121fcdf>] submit_bh_wbc+0xfe/0x109
[ 9.098358] [<ffffffff8121fd0a>] submit_bh+0x10/0x12
[ 9.100083] [<ffffffff8122004f>] block_read_full_page+0x28f/0x2ab
[ 9.102017] [<ffffffff81221cdc>] ? I_BDEV+0x12/0x12
[ 9.103727] [<ffffffff8118d159>] ? __add_to_page_cache_locked+0x2b6/0x394
[ 9.105794] [<ffffffff81222467>] ? blkdev_writepages+0x10/0x10
[ 9.107697] [<ffffffff8122247f>] blkdev_readpage+0x18/0x1a
[ 9.109535] [<ffffffff8118ead4>] do_read_cache_page+0xb7/0x2ef
[ 9.111435] [<ffffffff8118ed28>] read_cache_page+0x1c/0x1e
[ 9.113264] [<ffffffff815394d5>] read_dev_sector+0x30/0xb5
[ 9.115090] [<ffffffff8153beb9>] read_lba+0xa2/0x121
[ 9.116830] [<ffffffff8153c422>] ? efi_partition+0xd0/0x517
[ 9.118674] [<ffffffff8153c443>] efi_partition+0xf1/0x517
[ 9.120490] [<ffffffff81559198>] ? vsnprintf+0x85/0x3b1
[ 9.122267] [<ffffffff81559571>] ? snprintf+0x36/0x3e
[ 9.124013] [<ffffffff8153b455>] check_partition+0x11c/0x1b2
[ 9.125899] [<ffffffff8153b455>] ? check_partition+0x11c/0x1b2
[ 9.127800] [<ffffffff81539ac9>] rescan_partitions+0x7c/0x252
[ 9.129682] [<ffffffff81cb0586>] ? mutex_unlock+0xe/0x10
[ 9.131485] [<ffffffff81223400>] __blkdev_get+0x1c4/0x3dc
[ 9.133290] [<ffffffff812237de>] blkdev_get+0x1c6/0x2fd
[ 9.135066] [<ffffffff815375a0>] add_disk+0x42d/0x456
[ 9.136826] [<ffffffff812229b0>] ? revalidate_disk+0x78/0x84
[ 9.138697] [<ffffffff81613b49>] ? vp_get+0x57/0x67
[ 9.140417] [<ffffffff817557cc>] virtblk_probe+0x560/0x641
[ 9.142255] [<ffffffff8161062b>] virtio_dev_probe+0x111/0x187
[ 9.144127] [<ffffffff817294ef>] driver_probe_device+0x118/0x261
[ 9.146062] [<ffffffff817296ab>] __driver_attach+0x73/0x95
[ 9.147914] [<ffffffff81729638>] ? driver_probe_device+0x261/0x261
[ 9.149856] [<ffffffff81727959>] bus_for_each_dev+0x6f/0x87
[ 9.151712] [<ffffffff81728fa3>] driver_attach+0x1e/0x20
[ 9.153512] [<ffffffff81728b75>] bus_add_driver+0xf2/0x1e4
[ 9.155339] [<ffffffff827ff248>] ? init_cryptoloop+0x28/0x28
[ 9.157196] [<ffffffff8172a407>] driver_register+0x8a/0xc6
[ 9.159003] [<ffffffff827ff248>] ? init_cryptoloop+0x28/0x28
[ 9.160858] [<ffffffff816104b7>] register_virtio_driver+0x2b/0x2d
[ 9.162793] [<ffffffff827ff2a2>] init+0x5a/0x87
[ 9.164440] [<ffffffff81000402>] do_one_initcall+0xe7/0x177
[ 9.166298] [<ffffffff827af0b2>] kernel_init_freeable+0x1ca/0x252
[ 9.168240] [<ffffffff81ca46e2>] kernel_init+0xe/0xf5
[ 9.169982] [<ffffffff81cb2c72>] ret_from_fork+0x22/0x50
[ 9.171754] [<ffffffff81ca46d4>] ? rest_init+0x13b/0x13b
[ 9.173542] Code: 04 75 18 83 7f 08 00 74 1c 48 8b 05 6b 19 ed 00 48 3b 47 18 74 0f 48 89 47 18 c3 55 48 89 e5 e8 2b ff ff ff 5d c3 66 66 66 66 90 <44> 8b 47 08 31 c0 45 85 c0 0f 84 5f 01 00 00 48 8b 76 18 48 89
[ 9.186592] RIP [<ffffffff815336b0>] blk_wb_wait+0x5/0x174
[ 9.188533] RSP <ffff8800120277b8>
[ 9.189968] CR2: 0000000000000008
[ 9.191392] ---[ end trace 75dbd78af8037ee6 ]---
[ 9.193041] Kernel panic - not syncing: Fatal exception
FYI, raw QEMU command line is:
qemu-system-x86_64 -enable-kvm -cpu SandyBridge -kernel /pkg/linux/x86_64-nfsroot/gcc-5/1131f64d74958d495d8a6d5f9b981e86ed3beb7a/vmlinuz-4.6.0-rc1-00028-g1131f64 -append 'root=/dev/ram0 user=lkp job=/lkp/scheduled/vm-kbuild-yocto-x86_64-43/bisect_boot-1-yocto-minimal-x86_64.cgz-x86_64-nfsroot-1131f64d74958d495d8a6d5f9b981e86ed3beb7a-20160401-52945-110sl1r-0.yaml ARCH=x86_64 kconfig=x86_64-nfsroot branch=linux-devel/devel-catchup-201604011147 commit=1131f64d74958d495d8a6d5f9b981e86ed3beb7a BOOT_IMAGE=/pkg/linux/x86_64-nfsroot/gcc-5/1131f64d74958d495d8a6d5f9b981e86ed3beb7a/vmlinuz-4.6.0-rc1-00028-g1131f64 max_uptime=600 RESULT_ROOT=/result/boot/1/vm-kbuild-yocto-x86_64/yocto-minimal-x86_64.cgz/x86_64-nfsroot/gcc-5/1131f64d74958d495d8a6d5f9b981e86ed3beb7a/0 LKP_SERVER=inn earlyprintk=ttyS0,115200 systemd.log_level=err debug apic=debug sysrq_always_enabled rcupdate.rcu_cpu_stall_timeout=100 panic=-1 softlockup_panic=1 nmi_watchdog=panic oops=panic load_ramdisk=2 prompt_ramdisk=0 console=ttyS0,115200 console=tty0 vga=normal rw ip=::::vm-kbuild-yocto-x86_64-43::dhcp drbd.minor_count=8' -initrd /fs/sdd1/initrd-vm-kbuild-yocto-x86_64-43 -m 320 -smp 1 -device e1000,netdev=net0 -netdev user,id=net0 -boot order=nc -no-reboot -watchdog i6300esb -rtc base=localtime -drive file=/fs/sdd1/disk0-vm-kbuild-yocto-x86_64-43,media=disk,if=virtio -pidfile /dev/shm/kboot/pid-vm-kbuild-yocto-x86_64-43 -serial file:/dev/shm/kboot/serial-vm-kbuild-yocto-x86_64-43 -daemonize -display none -monitor null
Thanks,
Kernel Test Robot
On 04/01/2016 02:40 AM, kernel test robot wrote:
> FYI, we noticed the below changes on
>
> https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git wb-buf-throttle
> commit 1131f64d74958d495d8a6d5f9b981e86ed3beb7a ("blk-mq: don't throttle for virtual devices")
>
>
> +------------------------------------------+------------+------------+
> | | f21fb0e42c | 1131f64d74 |
> +------------------------------------------+------------+------------+
> | boot_successes | 6 | 0 |
> | boot_failures | 0 | 6 |
> | BUG:unable_to_handle_kernel | 0 | 6 |
> | Oops | 0 | 6 |
> | RIP:blk_wb_wait | 0 | 6 |
> | Kernel_panic-not_syncing:Fatal_exception | 0 | 6 |
> | backtrace:init | 0 | 6 |
> | backtrace:kernel_init_freeable | 0 | 6 |
> +------------------------------------------+------------+------------+
>
>
>
> [ 8.897469] FDC 0 is a S82078B
> [ 8.984074] brd: module loaded
> [ 9.030737] loop: module loaded
> [ 9.045718] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
> [ 9.048069] IP: [<ffffffff815336b0>] blk_wb_wait+0x5/0x174
Fixed:
http://git.kernel.dk/cgit/linux-block/commit/?h=wb-buf-throttle&id=811ea72827a70139a0520ec07b39d6a4baa62de1
it was introduced by this commit:
http://git.kernel.dk/cgit/linux-block/commit/?h=wb-buf-throttle&id=1131f64d74958d495d8a6d5f9b981e86ed3beb7a
and both will be folded for the next release.
--
Jens Axboe