Description of problem:


Kernel mount/fuse mount to Ceph FS hangs intermittently.  This started happening recently in the latest few hours. Tried using all monitor server in mount command, still same problem.

For the segment of strace output is below:

read(8, "# /etc/security/limits.conf\n#\n#T"..., 4096) = 2422
read(8, "", 4096)                       = 0
close(8)                                = 0
munmap(0x7f5c84084000, 4096)            = 0
openat(AT_FDCWD, "/etc/security/limits.d", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = 8
brk(NULL)                               = 0x7f5c861d1000
brk(0x7f5c861f5000)                     = 0x7f5c861f5000
getdents(8, /* 3 entries */, 32768)     = 88
open("/usr/lib64/gconv/gconv-modules.cache", O_RDONLY) = 9
fstat(9, {st_mode=S_IFREG|0644, st_size=26254, ...}) = 0
mmap(NULL, 26254, PROT_READ, MAP_SHARED, 9, 0) = 0x7f5c8407e000
close(9)                                = 0
futex(0x7f5c8360ba80, FUTEX_WAKE_PRIVATE, 2147483647) = 0
getdents(8, /* 0 entries */, 32768)     = 0
brk(NULL)                               = 0x7f5c861f5000
brk(NULL)                               = 0x7f5c861f5000
brk(0x7f5c861ed000)                     = 0x7f5c861ed000
brk(NULL)                               = 0x7f5c861ed000
close(8)                                = 0
open("/etc/security/limits.d/20-nproc.conf", O_RDONLY) = 8
fstat(8, {st_mode=S_IFREG|0644, st_size=191, ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f5c8407d000
read(8, "# Default limit for number of us"..., 4096) = 191
read(8, "", 4096)                       = 0
close(8)                                = 0
munmap(0x7f5c8407d000, 4096)            = 0
setrlimit(RLIMIT_NPROC, {rlim_cur=29182, rlim_max=29182}) = 0
setpriority(PRIO_PROCESS, 0, 0)         = 0
socket(AF_NETLINK, SOCK_RAW, NETLINK_AUDIT) = 8
fcntl(8, F_SETFD, FD_CLOEXEC)           = 0
sendto(8, "\230\0\0\0Q\4\5\0\3\0\0\0\0\0\0\0op=PAM:session_o"..., 152, 0, {sa_family=AF_NETLINK, pid=0, groups=00000000}, 12) = 152
poll([{fd=8, events=POLLIN}], 1, 500)   = 1 ([{fd=8, revents=POLLIN}])
recvfrom(8, "$\0\0\0\2\0\0\0\3\0\0\0D\357\377\377\0\0\0\0\230\0\0\0Q\4\5\0\3\0\0\0"..., 8988, MSG_PEEK|MSG_DONTWAIT, {sa_family=AF_NETLINK, pid=0, groups=00000000}, [12]) = 36
recvfrom(8, "$\0\0\0\2\0\0\0\3\0\0\0D\357\377\377\0\0\0\0\230\0\0\0Q\4\5\0\3\0\0\0"..., 8988, MSG_DONTWAIT, {sa_family=AF_NETLINK, pid=0, groups=00000000}, [12]) = 36
close(8)                                = 0
getrlimit(RLIMIT_NPROC, {rlim_cur=29182, rlim_max=29182}) = 0
setrlimit(RLIMIT_NPROC, {rlim_cur=RLIM64_INFINITY, rlim_max=RLIM64_INFINITY}) = 0
clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x7f5c84078b10) = 18728
close(4)                                = 0
select(7, [3 6], [], NULL, NULL


Version-Release number of selected component (if applicable):


cat BaseOS-3.1.3-2017-11-22/installed-debs | grep ceph 
ii  ceph-common                          12.2.1-42redhat1xenial                     amd64        common utilities to mount and interact with a ceph storage cluster
ii  ceph-fuse                            12.2.1-42redhat1xenial                     amd64        FUSE-based client for the Ceph distributed file system
ii  libcephfs2                           12.2.1-42redhat1xenial                     amd64        Ceph distributed file system client library
ii  python-cephfs                        12.2.1-42redhat1xenial                     amd64        Python 2 libraries for the Ceph libcephfs library


 cat BaseOS-3.1.3-2017-11-22/uname 
Linux BaseOS-3.1.3-2017-11-22 4.13.0-25-generic #29~16.04.2-Ubuntu SMP Tue Jan 9 12:16:39 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

How reproducible:

100%reproduced

Steps to Reproduce:
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Actual results:


Expected results:


Additional info: