Re: [lkp-robot] [fs] 332391a993: WARNING:at_fs/iomap.c:#iomap_dio_complete

From: Jeff Moyer
Date: Tue Oct 10 2017 - 10:36:37 EST


kernel test robot <xiaolong.ye@xxxxxxxxx> writes:

> FYI, we noticed the following commit (built with gcc-6):
>
> commit: 332391a9935da939319e473b4680e173df75afcf ("fs: Fix page cache
> inconsistency when mixing buffered and AIO DIO")
> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master

[...]

> [ 170.063040] WARNING: CPU: 0 PID: 33 at fs/iomap.c:731 iomap_dio_complete+0x129/0x130
> [ 170.068758] Modules linked in: xfs dm_mod rpcsec_gss_krb5
> auth_rpcgss nfsv4 dns_resolver sr_mod cdrom sg ata_generic pata_acpi
> ppdev ata_piix parport_pc snd_pcm snd_timer snd soundcore serio_raw
> pcspkr i2c_piix4 libata floppy parport ip_tables
> [ 170.074819] CPU: 0 PID: 33 Comm: kworker/0:1 Not tainted 4.14.0-rc1-00056-g332391a #1
> [ 170.077915] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
> [ 170.081047] Workqueue: dio/vda iomap_dio_complete_work
> [ 170.081974] task: ffff88012e504a80 task.stack: ffffc90000758000
> [ 170.084465] RIP: 0010:iomap_dio_complete+0x129/0x130
> [ 170.085381] RSP: 0018:ffffc9000075be18 EFLAGS: 00010286
> [ 170.087536] RAX: 00000000fffffff0 RBX: 0000000000000001 RCX: 000000000000000c
> [ 170.088853] RDX: 0000000000000000 RSI: ffffc9000075bc50 RDI: ffff880075715da9
> [ 170.092113] RBP: ffffc9000075be30 R08: ffffc9000075bcf0 R09: ffff880075715da8
> [ 170.093254] R10: 000000000000000c R11: 0000000000000000 R12: ffff88007afa9300
> [ 170.096475] R13: ffff88007ac7ad80 R14: ffff88007afa9338 R15: ffff88007afa9330
> [ 170.098187] FS: 0000000000000000(0000) GS:ffff88013fc00000(0000) knlGS:0000000000000000
> [ 170.101322] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [ 170.102265] CR2: 00007f3ad48a8020 CR3: 000000007fe16000 CR4: 00000000000006f0
> [ 170.104631] Call Trace:
> [ 170.105146] iomap_dio_complete_work+0x25/0x80
> [ 170.106704] process_one_work+0x198/0x3e0
> [ 170.107874] worker_thread+0x4e/0x3e0
> [ 170.108522] kthread+0x114/0x150
> [ 170.110683] ? process_one_work+0x3e0/0x3e0
> [ 170.111362] ? kthread_create_on_node+0x40/0x40
> [ 170.113111] ret_from_fork+0x25/0x30
> [ 170.113752] Code: c9 74 17 49 63 74 24 28 41 8b 54 24 24 85 f6 0f 84
> 2a ff ff ff e9 3e ff ff ff 41 8b 74 24 28 49 8b 45 00 48 63 de e9 39
> ff ff ff <0f> ff eb ca 0f 1f 00 0f 1f 44 00 00 55 48 83 ef 30 48 89 e5
> 41

The test case is doing buffered and direct writes to the same file from
different processes, and is intended to trigger the case where
invalidate_inode_pages2_range fails. I guess it's easier to hit now
since we defer completion to a worker thread? Anyway, we should update
xfstests to ignore this warning.

Cheers,
Jeff

[...]

> generic/027
> generic/070
> generic/117
> generic/208
> 2017-10-09 15:50:42 ./check generic/027 generic/070 generic/117 generic/208
> FSTYP -- xfs (non-debug)
> PLATFORM -- Linux/x86_64 vm-kbuild-4G-1 4.14.0-rc1-00056-g332391a
> MKFS_OPTIONS -- -f -bsize=4096 /dev/vdd
> MOUNT_OPTIONS -- /dev/vdd /fs/scratch
>
> generic/027 54s
> generic/070 34s
> generic/117 58s
> generic/208 200s
> _check_dmesg: something found in dmesg (see /lkp/benchmarks/xfstests/results//generic/208.dmesg)
> Ran: generic/027 generic/070 generic/117 generic/208
> Failures: generic/208
> Failed 1 of 4 tests