[LU-18518] lustre device mount stuck

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.17.0
• Severity: 3
• Assignee: Jian Yu
• Reporter: Shuichi Ihara

Description

This is an environment of kernel and Lustre which is built by clang instead of gcc on ubuntu24.04.

$ sudo dmesg | grep 'Linux version'
[    0.000000] Linux version 6.8.12clang (ubuntu@u2404-srv1) (Ubuntu clang version 18.1.3 (1ubuntu1), Ubuntu LLD 18.1.3) #1 SMP PREEMPT_DYNAMIC Thu Dec  5 09:13:19 UTC 2024 (Ubuntu 6.8.0-49.49-generic 6.8.12)

Lustre master branch was able to be built by clang except LU-18517.

$ sh ./autogen.sh; ./configure CC=clang 'CFLAGS=-Wno-frame-address -Wno-incompatible-function-pointer-types' --with-linux=/home/ubuntu/linux-source-6.8.0/ LLVM=1

$ sudo modprobe lustre
$ modinfo lustre
filename:       /lib/modules/6.8.0-49-generic-clang-2/updates/kernel/fs/lustre/lustre.ko
alias:          fs-lustre
author:         OpenSFS, Inc. <http://www.lustre.org/>
description:    Lustre Client File System
version:        2.16.50_87_g64e158b
license:        GPL
vermagic:       6.8.0-49-generic-clang-2 SMP preempt mod_unload modversions 
name:           lustre
retpoline:      Y
depends:        ptlrpc,libcfs,obdclass,mdc,lmv,lov,lnet,fid
srcversion:     F6E501204471DEE570F0971

However, when a device is mounted as Lustre, it hangs. Even device is just MGT.

$ sudo mkfs.lustre --mgs --device-size=100000 /tmp/mdt
$ sudo mount /tmp/mdt -o loop /mnt/ -t lustre

mount doesn't complete and stuck here.

[25204.948835] ------------[ cut here ]------------
[25204.948843] UBSAN: array-index-out-of-bounds in /home/ubuntu/lustre-release/ldiskfs/htree_lock.c:874:35
[25204.951242] index 1 is out of range for type 'struct htree_lock_node[0]'
[25204.952946] CPU: 15 PID: 74322 Comm: mount.lustre Tainted: G           OE      6.8.0-49-generic-clang-2 #4
[25204.952960] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009)/Incus, BIOS unknown 02/02/2022
[25204.952966] Call Trace:
[25204.952989]  <TASK>
[25204.952997]  dump_stack_lvl+0x2f/0xa0
[25204.953051]  dump_stack+0x10/0x20
[25204.953058]  __ubsan_handle_out_of_bounds+0xe8/0x110
[25204.953094]  htree_lock_alloc+0xdf/0x1b0 [ldiskfs]
[25204.953204]  ldiskfs_htree_lock_alloc+0x18/0x30 [ldiskfs]
[25204.953287]  osd_key_init+0x1c2/0x370 [osd_ldiskfs]
[25204.953350]  keys_fill+0x8f/0x120 [obdclass]
[25204.953503]  lu_context_init+0x15b/0x190 [obdclass]
[25204.953644]  lu_env_init+0x1a/0x30 [obdclass]
[25204.953817]  obd_setup+0x1f5/0x3e0 [obdclass]
[25204.953961]  class_setup+0x487/0x840 [obdclass]
[25204.954103]  class_process_config+0x1bdf/0x31a0 [obdclass]
[25204.954247]  ? libcfs_debug_msg+0xab7/0xe20 [libcfs]
[25204.954291]  ? __kmalloc+0x1bd/0x460
[25204.954304]  do_lcfg+0x495/0x830 [obdclass]
[25204.954447]  lustre_start_simple+0x136/0x1e0 [obdclass]
[25204.954590]  server_fill_super+0x7c8/0x14d0 [ptlrpc]
[25204.954853]  lustre_fill_super+0x255/0x480 [lustre]
[25204.954961]  ? __pfx_lustre_fill_super+0x10/0x10 [lustre]
[25204.955050]  mount_nodev+0x52/0xb0
[25204.955065]  lustre_mount+0x18/0x30 [lustre]
[25204.955200]  legacy_get_tree+0x2c/0x60
[25204.955221]  vfs_get_tree+0x2f/0xf0
[25204.955228]  do_new_mount+0x143/0x3a0
[25204.955239]  path_mount+0x311/0x540
[25204.955245]  __se_sys_mount+0x174/0x1f0
[25204.955251]  __x64_sys_mount+0x25/0x40
[25204.955256]  x64_sys_call+0x2726/0x2be0
[25204.955268]  do_syscall_64+0x89/0x160
[25204.955276]  ? fsnotify_destroy_marks+0x87/0x1c0
[25204.955288]  ? call_rcu+0x25/0x60
[25204.955301]  ? evict+0x202/0x230
[25204.955318]  ? kmem_cache_free+0x2b/0x2d0
[25204.955329]  ? fpregs_restore_userregs+0x81/0x150
[25204.955348]  ? switch_fpu_return+0xe/0x20
[25204.955354]  ? arch_exit_to_user_mode_prepare+0x68/0x70
[25204.955365]  ? syscall_exit_to_user_mode+0xb6/0xe0
[25204.955375]  ? do_syscall_64+0x95/0x160
[25204.955383]  ? __memcg_slab_free_hook+0x48/0x1d0
[25204.955391]  ? __fput+0x1a7/0x2d0
[25204.955396]  ? kmem_cache_free+0x193/0x2d0
[25204.955402]  ? __fput+0x1a7/0x2d0
[25204.955407]  ? __fput_sync+0x15/0x20
[25204.955411]  ? arch_exit_to_user_mode_prepare+0x22/0x70
[25204.955417]  ? syscall_exit_to_user_mode+0xb6/0xe0
[25204.955422]  ? do_syscall_64+0x95/0x160
[25204.955429]  ? irqentry_exit+0x12/0x50
[25204.955434]  ? exc_page_fault+0x74/0xf0
[25204.955444]  entry_SYSCALL_64_after_hwframe+0x78/0x80
[25204.955465] RIP: 0033:0x75a56932af0e
[25204.955473] Code: 48 8b 0d 0d 7f 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d da 7e 0d 00 f7 d8 64 89 01 48
[25204.955479] RSP: 002b:00007ffe239b4078 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
[25204.955487] RAX: ffffffffffffffda RBX: 00007ffe239b83d8 RCX: 000075a56932af0e
[25204.955492] RDX: 000061f0e643668a RSI: 00007ffe239b7280 RDI: 000061f0e71dd930
[25204.955495] RBP: 00007ffe239b82b0 R08: 000061f0e71dd950 R09: 0000000000000007
[25204.955499] R10: 0000000001000000 R11: 0000000000000206 R12: 0000000000000005
[25204.955503] R13: 0000000000000000 R14: 000061f0e6439b48 R15: 000075a5695a9000
[25204.955510]  </TASK>
[25204.955556] ---[ end trace ]---