We have reproduced the same issue on the Linus' tree (24c534bb16): https://s3.amazonaws.com/archive.travis-ci.org/jobs/209936923/log.txt [ 702.992802] BUG: Dentry ffff95b3006c4b40{i=8deba,n=default} still in use (1) [unmount of proc proc] [ 703.002345] ------------[ cut here ]------------ [ 703.002355] WARNING: CPU: 1 PID: 1248 at fs/dcache.c:1445 umount_check+0x81/0x90 [ 703.002357] Modules linked in: [ 703.002363] CPU: 1 PID: 1248 Comm: zdtm_ct Not tainted 4.11.0-rc1+ #1 [ 703.002365] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 703.002367] Call Trace: [ 703.002377] dump_stack+0x85/0xc9 [ 703.002383] __warn+0xd1/0xf0 [ 703.002389] ? dentry_free+0x90/0x90 [ 703.002392] warn_slowpath_null+0x1d/0x20 [ 703.002394] umount_check+0x81/0x90 [ 703.002396] d_walk+0xef/0x4e0 [ 703.002398] ? do_one_tree+0x26/0x40 [ 703.002405] do_one_tree+0x26/0x40 [ 703.002407] shrink_dcache_for_umount+0x2d/0xa0 [ 703.002412] generic_shutdown_super+0x1f/0x100 [ 703.002415] kill_anon_super+0x12/0x20 [ 703.002419] proc_kill_sb+0x40/0x50 [ 703.002422] deactivate_locked_super+0x43/0x70 [ 703.002425] deactivate_super+0x46/0x60 [ 703.002429] cleanup_mnt+0x3f/0x80 [ 703.002431] __cleanup_mnt+0x12/0x20 [ 703.002434] task_work_run+0x83/0xc0 [ 703.002439] do_exit+0x318/0xc90 [ 703.002443] ? trace_hardirqs_on_caller+0xf9/0x1c0 [ 703.002447] do_group_exit+0x4c/0xc0 [ 703.002450] SyS_exit_group+0x14/0x20 [ 703.002455] entry_SYSCALL_64_fastpath+0x23/0xc6 [ 703.002459] RIP: 0033:0x2aac6fecf1b9 [ 703.002461] RSP: 002b:00007ffe9c78f7e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 703.002465] RAX: ffffffffffffffda RBX: 0000000000000010 RCX: 00002aac6fecf1b9 [ 703.002467] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 703.002468] RBP: 00007ffe9c78f7e0 R08: 000000000000003c R09: 00000000000000e7 [ 703.002470] R10: ffffffffffffff60 R11: 0000000000000246 R12: 0000000000000001 [ 703.002472] R13: 00002aac701cde80 R14: 0000000000000000 R15: 00007ffe9c78f750 [ 703.002484] ---[ end trace a371a2301e08cbc1 ]--- zdtm_ct is a small program to create a container: https://github.com/xemul/criu/blob/master/test/zdtm_ct.c On Fri, Mar 10, 2017 at 11:28 AM, Andrei Vagin <avagin@xxxxxxxxx> wrote: > Hello, > > We run CRIU tests on linux-next periodically and here is a new bug: > > [ 430.017231] BUG: Dentry ffff8e4ab9a7b6c0{i=41b2e,n=default} still > in use (1) [unmount of proc proc] > [ 430.027843] ------------[ cut here ]------------ > [ 430.027854] WARNING: CPU: 1 PID: 24110 at fs/dcache.c:1445 > umount_check+0x81/0x90 > [ 430.027857] Modules linked in: bridge stp llc nf_conntrack_netlink > nfnetlink autofs4 netlink_diag af_packet_diag udp_diag tcp_diag > inet_diag unix_diag ip6table_filter ip6_tables binfmt_misc dm_crypt > ppdev xt_tcpudp xt_conntrack xt_mark iptable_filter ipt_MASQUERADE > nf_nat_masquerade_ipv4 xt_addrtype iptable_nat nf_conntrack_ipv4 > nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack libcrc32c ip_tables > x_tables parport_pc input_leds serio_raw parport pvpanic i2c_piix4 > mac_hid btrfs xor raid6_pq crct10dif_pclmul crc32_pclmul > ghash_clmulni_intel aesni_intel aes_x86_64 crypto_simd cryptd > glue_helper psmouse virtio_scsi > [ 430.027962] CPU: 1 PID: 24110 Comm: zdtm_ct Not tainted > 4.11.0-rc1-next-20170309 #1 > [ 430.027964] Hardware name: Google Google Compute Engine/Google > Compute Engine, BIOS Google 01/01/2011 > [ 430.027966] Call Trace: > [ 430.027975] dump_stack+0x85/0xc9 > [ 430.027983] __warn+0xd1/0xf0 > [ 430.027989] ? dentry_free+0x90/0x90 > [ 430.027993] warn_slowpath_null+0x1d/0x20 > [ 430.027996] umount_check+0x81/0x90 > [ 430.027999] d_walk+0xef/0x4e0 > [ 430.028005] ? do_one_tree+0x26/0x40 > [ 430.028015] do_one_tree+0x26/0x40 > [ 430.028019] shrink_dcache_for_umount+0x2d/0xa0 > [ 430.028024] generic_shutdown_super+0x1f/0x100 > [ 430.028028] kill_anon_super+0x12/0x20 > [ 430.028033] proc_kill_sb+0x40/0x50 > [ 430.028037] deactivate_locked_super+0x43/0x70 > [ 430.028041] deactivate_super+0x46/0x60 > [ 430.028047] cleanup_mnt+0x3f/0x80 > [ 430.028050] __cleanup_mnt+0x12/0x20 > [ 430.028056] task_work_run+0x83/0xc0 > [ 430.028061] do_exit+0x318/0xc90 > [ 430.028068] ? trace_hardirqs_on_caller+0xf9/0x1c0 > [ 430.028073] do_group_exit+0x4c/0xc0 > [ 430.028077] SyS_exit_group+0x14/0x20 > [ 430.028083] entry_SYSCALL_64_fastpath+0x23/0xc2 > [ 430.028086] RIP: 0033:0x2af672eb81b9 > [ 430.028088] RSP: 002b:00007fffbccef618 EFLAGS: 00000246 ORIG_RAX: > 00000000000000e7 > [ 430.028092] RAX: ffffffffffffffda RBX: 0000000000000010 RCX: 00002af672eb81b9 > [ 430.028094] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 > [ 430.028096] RBP: 00007fffbccef610 R08: 000000000000003c R09: 00000000000000e7 > [ 430.028098] R10: ffffffffffffff60 R11: 0000000000000246 R12: 0000000000000001 > [ 430.028100] R13: 00002af6731b6e80 R14: 0000000000000000 R15: 00007fffbccef580 > [ 430.028137] ---[ end trace 0cacf4b67ee7d0c5 ]--- > [ 430.028959] VFS: Busy inodes after unmount of proc. Self-destruct > in 5 seconds. Have a nice day... > > The kernel version is 4.11.0-rc1-next-20170309. All logs can be found > here https://s3.amazonaws.com/archive.travis-ci.org/jobs/209578615/log.txt.