[LU-672] mdd had panic on getting version for non existent file.

• Type: Bug
• Resolution: Fixed
• Priority: Major
• Fix Version/s: Lustre 2.2.0
• Affects Version/s: Lustre 2.1.0
• Severity: 3
• Assignee: WC Triage
• Reporter: Alexey Lyashkov

Description

Lustre: DEBUG MARKER: == replay-vbr test 1a: open and close do not change versions == 17:09:05 (1315440545)
LustreError: 30227:0:(mdd_object.c:2427:mdd_version_get()) ASSERTION(mdd_object_exists(mdd_obj)) failed
LustreError: 30227:0:(mdd_object.c:2427:mdd_version_get()) LBUG
Pid: 30227, comm: lctl

Call Trace:
[<ffffffffa0942857>] libcfs_debug_dumpstack+0x57/0x80 [libcfs]
[<ffffffffa0942e95>] lbug_with_loc+0x75/0xe0 [libcfs]
[<ffffffffa094dd06>] libcfs_assertion_failed+0x66/0x70 [libcfs]
[<ffffffffa0df61da>] mdd_version_get+0x3a/0xa0 [mdd]
[<ffffffffa0ecc969>] cml_version_get+0x49/0xc0 [cmm]
[<ffffffffa0e4edd7>] mdt_iocontrol+0x527/0x800 [mdt]
[<ffffffffa0943983>] ? cfs_alloc+0x63/0x90 [libcfs]
[<ffffffffa0a21434>] class_handle_ioctl+0x1524/0x2390 [obdclass]
[<ffffffff81135d69>] ? __do_fault+0x439/0x500
[<ffffffffa0a0b313>] obd_class_ioctl+0x53/0x240 [obdclass]
[<ffffffff81180172>] vfs_ioctl+0x22/0xa0
[<ffffffff81180314>] do_vfs_ioctl+0x84/0x580
[<ffffffff81136aed>] ? handle_mm_fault+0x1ed/0x2b0
[<ffffffff81180891>] sys_ioctl+0x81/0xa0
[<ffffffff81013172>] system_call_fastpath+0x16/0x1b

>>
rc = mdt_object_exists(obj);
if (rc < 0)

{ rc = -EREMOTE; /** * before calling version get the correct MDS should be * fid, this is error to find remote object here */ CERROR("nonlocal object "DFID"\n", PFID(fid)); }

else

{ version = mo_version_get(mti->mti_env, mdt_object_child(obj)); *(__u64 *)data->ioc_inlbuf2 = version; rc = 0; }

>>
so if lfs ... getfidversion called for non existent fid -mdt_object_exists return a 0, and mdd had assert hit.
question - why path2fid returned invalid fid, outside scope of that ticket.

i will attach fix tomorrow.

Issue Links

• Trackbacks: Changelog 2.2 version 2.2.0 Support for networks: o2iblnd OFED 1.5.4 Server support for kernels: 2.6.32220.4.2.el6 (RHEL6) Client support for unpatched kernels: 2.6.18274.18.1.el5 (RHEL5) 2.6.32220.4.2.el6 (RHEL6) 2.6.32.360....