Kernel Oops when mount NTFS partition with dcache

[Andiry]

Hi,

I'm trying dcache and encounter kernel oops when mount a NTFS partition. The configs are default.

[ 192.985965] ------------[ cut here ]------------
[ 192.985999] kernel BUG at fs/fast_dcache/namei.c:1121!
[ 192.986025] invalid opcode: 0000 [#1] SMP
[ 192.986051] Modules linked in: xfs libcrc32c pmem(O) snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hwdep snd_pcm intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm crct10dif_pclmul crc32_pclmul ghash_clmulni_intel bnep rfcomm bluetooth 6lowpan_iphc snd_seq_midi snd_seq_midi_event snd_rawmidi hid_logitech_dj joydev aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd snd_seq serio_raw snd_seq_device i915 snd_timer drm_kms_helper snd drm nuvoton_cir rc_core i2c_algo_bit soundcore mei_me mac_hid shpchp mei lpc_ich intel_smartconnect video binfmt_misc parport_pc ppdev lp parport hid_generic usbhid hid psmouse r8169 ahci mii libahci
[ 192.986554] CPU: 7 PID: 3680 Comm: pool Tainted: G O 3.14.0 #1
[ 192.986603] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./B75 Pro3-M, BIOS P1.40 05/11/2012
[ 192.986670] task: ffff880609792fd0 ti: ffff88049f45c000 task.ti: ffff88049f45c000
[ 192.986722] RIP: 0010:[] [] link_path_walk_fast+0xad4/0xae0
[ 192.986796] RSP: 0018:ffff88049f45d840 EFLAGS: 00010246
[ 192.986836] RAX: ffff8805fa2924c0 RBX: ffff8805c5557060 RCX: 0000000100160016
[ 192.986889] RDX: 000060f9e1a00e70 RSI: 0000000000160016 RDI: ffff8805c5557060
[ 192.986940] RBP: ffff88049f45d908 R08: ffff8800b8ba103f R09: ffff8805c5557060
[ 192.986975] R10: ffff8805fa2924c0 R11: 00000000801800c4 R12: ffff8806093c0000
[ 192.987007] R13: 0000000000000000 R14: ffff88049f45d9e0 R15: ffff88049f45d9e0
[ 192.987041] FS: 00007feb3d29f700(0000) GS:ffff88061e3c0000(0000) knlGS:0000000000000000
[ 192.987080] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 192.987121] CR2: 00007feb4a76b000 CR3: 00000005c6286000 CR4: 00000000001407e0
[ 192.987155] Stack:
[ 192.987167] 0000000031da9c35 0000000000000002 ffff8805fa2924c0 ffff8805c5557060
[ 192.987215] ffff8800b8ba1021 0000000000000000 ffff88049f45dac0 00000008c5557060
[ 192.987269] 0000000800000008 0000000000000000 ffff8805c5557001 ffff8800b8ba103f
[ 192.987311] Call Trace:
[ 192.987331] [] ? lookup_dcache+0x87/0x150
[ 192.987361] [] ? lockref_put_or_lock+0x50/0x90
[ 192.987390] [] ? dput+0x51/0xb0
[ 192.987416] [] path_lookupat+0x105/0xa50
[ 192.987445] [] ? ima_file_check+0x54/0x180
[ 192.987475] [] ? mntput+0x24/0x40
[ 192.987501] [] ? kmem_cache_alloc+0x31/0x140
[ 192.987530] [] ? getname_flags+0x4b/0x180
[ 192.987566] [] filename_lookup+0x2a/0xd0
[ 192.987610] [] user_path_at_empty+0x54/0xb0
[ 192.987653] [] ? cpumask_next_and+0x30/0x50
[ 192.987699] [] ? load_balance+0x1ce/0x8b0
[ 192.987748] [] ? update_rq_clock.part.72+0x18/0x40
[ 192.987793] [] ? native_sched_clock+0x2e/0xa0
[ 192.987823] [] ? sched_clock+0x9/0x10
[ 192.987850] [] ? sched_clock_cpu+0x9d/0xb0
[ 192.987882] [] ? __switch_to+0x1ab/0x500
[ 192.987912] [] ? gup_pud_range+0xfb/0x1c0
[ 192.987940] [] ? get_user_pages_fast+0xa2/0x190
[ 192.987972] [] ? unlock_page+0x23/0x30
[ 192.988001] [] ? get_futex_key+0x1cf/0x2b0
[ 192.988030] [] ? futex_wake+0x71/0x140
[ 192.988057] [] ? do_futex+0x10a/0xc40
[ 192.988084] [] user_path_at+0x11/0x20
[ 192.988111] [] vfs_fstatat+0x52/0xa0
[ 192.988138] [] SYSC_newlstat+0x22/0x40
[ 192.988165] [] ? SyS_futex+0x76/0x170
[ 192.988193] [] ? fillonedir+0xd0/0xd0
[ 192.988220] [] SyS_newlstat+0xe/0x10
[ 192.988248] [] system_call_fastpath+0x1a/0x1f
[ 192.988286] Code: ff ff ff 4c 89 54 24 10 48 89 4c 24 18 e9 b2 f8 ff ff b8 f7 ff ff ff e9 4b fb ff ff b8 f5 ff ff ff e9 41 fb ff ff 49 89 c4 eb 9c <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5
[ 192.988558] RIP [] link_path_walk_fast+0xad4/0xae0
[ 192.988598] RSP
[ 193.000736] ---[ end trace ec0e4c9b6d67adda ]---