[#LU-15902] osd_ea_lookup_rec()) ASSERTION( dir->i

FID may be reused after LFSCK, then a directory may become a regular file, and dt_lookup() on this object will crash because .do_lookup is NULL for regular file:

[34514.623550] LustreError: 22328:0:(osd_handler.c:5977:osd_ea_lookup_rec()) ASSERTION( dir->i_op->lookup != ((void *)0) ) failed: 
[34514.623552] LustreError: 22328:0:(osd_handler.c:5977:osd_ea_lookup_rec()) LBUG
[34514.623554] Pid: 22328, comm: ll_ost_out04_00 3.10.0-1160.49.1.el7_lustre.ddn16.x86_64 #1 SMP Mon Dec 20 11:42:01 PST 2021
[34514.623554] Call Trace:
[34514.623609] [<0>] libcfs_call_trace+0x90/0xf0 [libcfs]
[34514.623617] [<0>] lbug_with_loc+0x4c/0xa0 [libcfs]
[34514.623656] [<0>] osd_index_ea_lookup+0xc65/0xf70 [osd_ldiskfs]
[34514.623878] [<0>] out_index_lookup+0x4be/0x710 [ptlrpc]
[34514.623938] [<0>] out_handle+0x15ae/0x1c00 [ptlrpc]
[34514.623995] [<0>] tgt_request_handle+0xaee/0x15f0 [ptlrpc]
[34514.624054] [<0>] ptlrpc_server_handle_request+0x24b/0xab0 [ptlrpc]
[34514.624095] [<0>] ptlrpc_main+0xb34/0x1470 [ptlrpc]
[34514.624101] [<0>] kthread+0xd1/0xe0
[34514.624105] [<0>] ret_from_fork_nospec_begin+0x7/0x21
[34514.624238] [<0>] 0xfffffffffffffffe
[34514.624239] Kernel panic - not syncing: LBUG

[LU-15902] osd_ea_lookup_rec()) ASSERTION( dir->i_op->lookup != ((void *)0) ) Created: 30/May/22 Updated: 05/Jun/23 Resolved: 18/Jul/22
Status:	Resolved
Project:	Lustre
Component/s:	None
Affects Version/s:	None
Fix Version/s:	Lustre 2.16.0

[LU-15902] osd_ea_lookup_rec()) ASSERTION( dir->i_op->lookup != ((void *)0) ) Created: 30/May/22 Updated: 05/Jun/23 Resolved: 18/Jul/22