[LU-19881] BUG: unable to handle page fault for address in OSP

• Type: Bug
• Resolution: Fixed
• Priority: Medium
• Fix Version/s: Lustre 2.18.0
• Severity: 3
• Assignee: Alex Zhuravlev
• Reporter: Alex Zhuravlev

Description

few similar oops in osp:

[  140.066829] RIP: 0010:obd_get_max_mod_rpcs_in_flight+0x0/0x10 [obdclass]
[  140.066888] Code: 00 00 c3 31 c0 c3 0f 1f 40 00 8d 47 08 c3 66 66 2e 0f 1f 84 00 00 00 00 00 90 8b 87 40 02 00 00 c3 66 0f 1f 84 00 00 00 00 00 <0f> b7 87 d0 0e 00 00 c3 0f 1f 84 00 00 00 00 00 48 89 fe 48 8b 3d
[  140.066890] RSP: 0018:ffffa0f6d5b3fdf0 EFLAGS: 00010206
[  140.066891] RAX: ffffffffc1005c10 RBX: ffffa0f7effefbc8 RCX: 0000000000000000
[  140.066892] RDX: ffffa0f6816f5000 RSI: ffffffffc101b9e0 RDI: 0000000000000b90
[  140.066893] RBP: ffffa0f6816f5000 R08: ffffa0f6816f5000 R09: 0000000000000000
[  140.066894] R10: ffffa0f6816f5000 R11: ffffffff98344c35 R12: ffffffffc0528530
[  140.066895] R13: ffffa0f6cac85078 R14: ffffa0f6d1bd6000 R15: 0000000000000001
[  140.066897] FS:  00007f423defa940(0000) GS:ffffa0f7f8400000(0000) knlGS:0000000000000000
[  140.066898] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  140.066899] CR2: 0000000000001a60 CR3: 000000014e804000 CR4: 0000000000350eb0
[  140.066903] Call Trace:
[  140.066989]  max_mod_rpcs_in_flight_show+0x14/0x30 [osp]
[  140.067000]  sysfs_kf_seq_show+0x92/0xd0
[  140.067035]  seq_read_iter+0x100/0x460
[  140.067039]  vfs_read+0x229/0x3b0

[  111.511999] BUG: kernel NULL pointer dereference, address: 0000000000000b90
[  111.512002] #PF: supervisor write access in kernel mode
[  111.512004] #PF: error_code(0x0002) - not-present page
[  111.512005] PGD 140fa9067 P4D 140fa9067 PUD 14c67e067 PMD 0 
[  111.512008] Oops: 0002 [#1] SMP
[  111.512010] CPU: 0 PID: 18978 Comm: lctl Tainted: G        W  O      -------  ---  5.14.0 #24
[  111.512012] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014
[  111.512013] RIP: 0010:down_read_nested+0x37/0x140
[  111.512018] Code: 8d 7b 70 45 31 c9 31 d2 ff 74 24 10 41 b8 01 00 00 00 b9 01 00 00 00 89 ee e8 25 44 00 00 65 ff 05 26 b0 ef 52 be 00 01 00 00 <f0> 48 0f c1 33 48 81 c6 00 01 00 00 59 0f 88 c6 00 00 00 48 b8 07
[  111.512019] RSP: 0018:ffff9fdb8af5bdc0 EFLAGS: 00010282
[  111.512021] RAX: 0000000000000000 RBX: 0000000000000b90 RCX: 0000000000000000
[  111.512022] RDX: 0000000000000000 RSI: 0000000000000100 RDI: 0000000000000c00
[  111.512023] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
[  111.512023] R10: ffff9fdbce460000 R11: ffffffffad344c35 R12: 0000000000000b90
[  111.512024] R13: ffffffffffffffed R14: ffff9fdb826d2a00 R15: 0000000000000001
[  111.512027] FS:  00007f5a8456e940(0000) GS:ffff9fdcef400000(0000) knlGS:0000000000000000
[  111.512029] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  111.512030] CR2: 0000000000000b90 CR3: 0000000140fb4000 CR4: 0000000000350eb0
[  111.512033] Call Trace:
[  111.516957]  osp_conn_uuid_show+0x25/0xa0 [osp]
[  111.516969]  sysfs_kf_seq_show+0x92/0xd0
[  111.516971]  seq_read_iter+0x100/0x460
[  111.516975]  vfs_read+0x229/0x3b0
[  111.516978]  ksys_read+0x50/0xc0
[  111.516980]  do_syscall_64+0x38/0xe0
[  111.516982]  entry_SYSCALL_64_after_hwframe+0x4b/0x53

Issue Links

• is related to: LU-8066 Move lustre procfs handling to sysfs and debugfs.