The prev_chunk's dirent list is empty although it has num_entries as 112. Crashes at the following line as the dirents list is empty. chunk->reload_ck = glist_last_entry(&prev_chunk->dirents, mdcache_dir_entry_t, chunk_list)->ck; #0 0x00007fae938dc4ab in raise () from /lib64/libpthread.so.0 #1 0x000000000045549e in crash_handler (signo=11, info=0x7fae25f48eb0, ctx=0x7fae25f48d80) at /usr/src/debug/nfs-ganesha-2.5.3-ibm031.00-0.1.1-Source/MainNFSD/nfs_init.c:225 #2 <signal handler called> #3 mdcache_get_chunk (parent=0x7faa1001a290, prev_chunk=0x7fade0206350, whence=2147483647) at /usr/src/debug/nfs-ganesha-2.5.3-ibm031.00-0.1.1-Source/FSAL/Stackable_FSALs/FSAL_MDCACHE/mdcache_lru.c:909 #4 0x000000000054fbe9 in mdcache_populate_dir_chunk (directory=0x7faa1001a290, whence=2147483647, dirent=0x7fae25f49680, prev_chunk=0x7fade0206350, eod_met=0x7fae25f4967f) at /usr/src/debug/nfs-ganesha-2.5.3-ibm031.00-0.1.1-Source/FSAL/Stackable_FSALs/FSAL_MDCACHE/mdcache_helpers.c:2659 #5 0x0000000000551767 in mdcache_readdir_chunked (directory=0x7faa1001a290, whence=2147483647, dir_state=0x7fae25f49990, cb=0x43310f <populate_dirent>, attrmask=0, eod_met=0x7fae25f49e8b) at /usr/src/debug/nfs-ganesha-2.5.3-ibm031.00-0.1.1-Source/FSAL/Stackable_FSALs/FSAL_MDCACHE/mdcache_helpers.c:3053 #6 0x000000000053f39f in mdcache_readdir (dir_hdl=0x7faa1001a2c8, whence=0x7fae25f49970, dir_state=0x7fae25f49990, cb=0x43310f <populate_dirent>, attrmask=0, eod_met=0x7fae25f49e8b) at /usr/src/debug/nfs-ganesha-2.5.3-ibm031.00-0.1.1-Source/FSAL/Stackable_FSALs/FSAL_MDCACHE/mdcache_handle.c:639 #7 0x00000000004339f3 in fsal_readdir (directory=0x7faa1001a2c8, cookie=2147483647, nbfound=0x7fae25f49e8c, eod_met=0x7fae25f49e8b, attrmask=0, cb=0x495d70 <nfs3_readdir_callback>, opaque=0x7fae25f49e40) at /usr/src/debug/nfs-ganesha-2.5.3-ibm031.00-0.1.1-Source/FSAL/fsal_helper.c:1502 #8 0x0000000000495b57 in nfs3_readdir (arg=0x7fa8b4f75e80, req=0x7fa8b4f75678, res=0x7faad82c8c70) at /usr/src/debug/nfs-ganesha-2.5.3-ibm031.00-0.1.1-Source/Protocols/NFS/nfs3_readdir.c:289 #9 0x000000000044ccde in nfs_rpc_execute (reqdata=0x7fa8b4f75650) at /usr/src/debug/nfs-ganesha-2.5.3-ibm031.00-0.1.1-Source/MainNFSD/nfs_worker_thread.c:1290 #10 0x000000000044d4e8 in worker_run (ctx=0x4926600) at /usr/src/debug/nfs-ganesha-2.5.3-ibm031.00-0.1.1-Source/MainNFSD/nfs_worker_thread.c:1562 #11 0x000000000050c57f in fridgethr_start_routine (arg=0x4926600) at /usr/src/debug/nfs-ganesha-2.5.3-ibm031.00-0.1.1-Source/support/fridgethr.c:550 (gdb) frame 3 (gdb) p *prev_chunk $9 = {chunks = {next = 0x7faad808a570, prev = 0x7fade00000d8}, dirents = {next = 0x7fade0206360, prev = 0x7fade0206360}, parent = 0x0, chunk_lru = {q = {next = 0x0, prev = 0x0}, qid = LRU_ENTRY_L1, refcnt = 0, flags = 0, lane = 534, cf = 0}, reload_ck = 1453366958, next_ck = 0, num_entries = 112} Regards, Malahal. PS: code frome here: https://github.com/malahal/nfs-ganesha/commits/ibm2.5 for matching crash line numbers!