Ceph » Linux kernel client

xfstests generic/247 often fails with a warning:

[ 1135.748673] WARNING: CPU: 0 PID: 16554 at fs/xfs/xfs_file.c:756 xfs_file_dio_aio_write+0x265/0x2e0()
[ 1135.751323] Modules linked in:
[ 1135.752341] CPU: 0 PID: 16554 Comm: dd Not tainted 4.3.0-00048-g1e5adc1-dirty #969
[ 1135.754518] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 1135.756111] ffffffff81d4e6e5 ffff880039aebd50 ffffffff8142a3bc 0000000000000000
[ 1135.758392] ffff880039aebd88 ffffffff81061a5c ffff880034083d90 ffff880039aebe68
[ 1135.760687] ffff880034083f70 ffff880034083a80 ffff880039aebe90 ffff880039aebd98
[ 1135.762971] Call Trace:
[ 1135.763824] [<ffffffff8142a3bc>] dump_stack+0x44/0x58
[ 1135.765329] [<ffffffff81061a5c>] warn_slowpath_common+0x7c/0xc0
[ 1135.766888] [<ffffffff81061b55>] warn_slowpath_null+0x15/0x20
[ 1135.768188] [<ffffffff81337715>] xfs_file_dio_aio_write+0x265/0x2e0
[ 1135.769634] [<ffffffff810ff43a>] ? __audit_syscall_entry+0xaa/0xf0
[ 1135.771077] [<ffffffff81337a57>] xfs_file_write_iter+0xf7/0x110
[ 1135.772797] [<ffffffff81182715>] __vfs_write+0xa5/0xe0
[ 1135.774270] [<ffffffff81182d24>] vfs_write+0xa4/0x190
[ 1135.775752] [<ffffffff811a13d1>] ? __fget_light+0x61/0x90
[ 1135.777281] [<ffffffff811839d4>] SyS_write+0x44/0xa0
[ 1135.778777] [<ffffffff818c2f32>] entry_SYSCALL_64_fastpath+0x12/0x76

This is addressed in a mailing list post at:
https://lists.01.org/pipermail/lkp/2015-March/002459.html

...suggesting it is a known race. Expunge the test since it is a known issue outside krbd.