Ubuntu 16.04 running on z13 hardware is unable to configure blue ridge

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Problem Description
===========================
system Z Ubuntu 16.04 LTS can not correctly configured DS8870 2107 LUNs.

---uname output---
Linux ilabg3 4.4.0-33-generic #52-Ubuntu SMP Fri Jul 22 19:17:00 UTC 2016 s390x s390x s390x GNU/Linux

---Additional Hardware Info---
Z13 system using 16G FCP adapters to attach to FC fabric and IBM Blue ridge

 Machine Type = Z13 S390

Steps to Reproduce
============================
The initial kernel is 4.4.0-24-generic and all blue ridge devices can be configured normally.
After we upgrade kernel to 4.4.0-33 and reload BR code all BR devices can not be detect.

System log show:
[ 2645.893763] scsi 0:0:7:0: RAID IBM 2810XIV-LUN-0 0000 PQ: 0 ANSI: 5
[ 2645.895269] sysfs: cannot create duplicate filename '/bus/scsi/devices/0:0:7:0'
[ 2645.895310] ------------[ cut here ]------------
[ 2645.895311] WARNING: at /build/linux-o03cxz/linux-4.4.0/fs/sysfs/dir.c:31
[ 2645.895312] Modules linked in: rpcsec_gss_krb5 auth_rpcgss nfsv4 nfs lockd grace fscache qeth_l3 qeth ccwgroup vmur ib_iser rdma_cm iw_cm ib_cm ib_sa ib_mad ib_core sunrpc ib_addr iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi btrfs zlib_deflate raid10 raid456 async_memcpy async_raid6_recov async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 linear dm_round_robin ghash_s390 prng aes_s390 des_s390 des_generic sha512_s390 sha256_s390 sha1_s390 sha_common zfcp dasd_eckd_mod qdio scsi_transport_fc dasd_fba_mod dasd_mod scsi_dh_emc scsi_dh_rdac scsi_dh_alua dm_multipath
[ 2645.895338] CPU: 1 PID: 4008 Comm: sh Tainted: G W 4.4.0-33-generic #52-Ubuntu
[ 2645.895339] task: 00000000dfe436b0 ti: 000000007b97c000 task.ti: 000000007b97c000
[ 2645.895340] Krnl PSW : 0704d00180000000 00000000003a361c (sysfs_warn_dup+0x7c/0x98)
[ 2645.895350] R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 EA:3
               Krnl GPRS: 0000000000cf7039 0000000000cd9f3c 0000000000000043 00000000ef4d18a0
[ 2645.895351] 00000000003a3618 0000000000000000 000000007a49a000 00000000707b9178
[ 2645.895352] 0000000000c1d0e0 00000000ee71a780 0000000000000001 00000000ee71a780
[ 2645.895353] 00000000e9554b60 000000007ebdf000 00000000003a3618 000000007b97f9b8
[ 2645.895361] Krnl Code: 00000000003a360c: c020002f33e7 larl %r2,989dda
                          00000000003a3612: c0e5fff6befb brasl %r14,27b408
                         #00000000003a3618: a7f40001 brc 15,3a361a
                         >00000000003a361c: b904002d lgr %r2,%r13
                          00000000003a3620: ebbff0a00004 lmg %r11,%r15,160(%r15)
                          00000000003a3626: c0f4fffa5995 brcl 15,2ee950
                          00000000003a362c: a7390000 lghi %r3,0
                          00000000003a3630: a7f4ffec brc 15,3a3608
[ 2645.895370] Call Trace:
[ 2645.895372] ([<00000000003a3618>] sysfs_warn_dup+0x78/0x98)
[ 2645.895374] [<00000000003a3b30>] sysfs_do_create_link_sd.isra.0+0xf8/0x108
[ 2645.895378] [<00000000005c4044>] bus_add_device+0x13c/0x230
[ 2645.895379] [<00000000005c1758>] device_add+0x398/0x680
[ 2645.895385] [<00000000005f7a34>] scsi_sysfs_add_sdev+0xcc/0x2a8
[ 2645.895386] [<00000000005f4210>] scsi_probe_and_add_lun+0xcc0/0xe18
[ 2645.895387] [<00000000005f4c5a>] __scsi_scan_target+0xba/0x268
[ 2645.895389] [<00000000005f4f0a>] scsi_scan_target+0x102/0x120
[ 2645.895401] [<000003ff801095f6>] zfcp_unit_scsi_scan+0x7e/0x90 [zfcp]
[ 2645.895404] [<000003ff80109948>] zfcp_unit_add+0x168/0x1f0 [zfcp]
[ 2645.895407] [<000003ff80108564>] zfcp_sysfs_unit_add_store+0x54/0x70 [zfcp]
[ 2645.895408] [<00000000003a1d9a>] kernfs_fop_write+0x13a/0x190
[ 2645.895413] [<000000000030fcac>] vfs_write+0x94/0x1a0
[ 2645.895414] [<00000000003109be>] SyS_write+0x66/0xd8
[ 2645.895417] [<00000000007b86c6>] system_call+0xd6/0x264
[ 2645.895418] [<000003ffb10df6e8>] 0x3ffb10df6e8
[ 2645.895419] Last Breaking-Event-Address:
[ 2645.895420] [<00000000003a3618>] sysfs_warn_dup+0x78/0x98
[ 2645.895421] ---[ end trace a9b757385c995a64 ]---
[ 2645.895535] scsi 0:0:7:0: failed to add device: -17

== Comment: #1 - XIANG ZHANG <email address hidden> - 2016-07-26 02:34:39 ==
I know the Bug 139096, not sure the same symptom

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Default Comment by Bridge

[Joseph Salisbury (jsalisbury)]

I'd like to perform a kernel bisect to figure out which commit caused this regression. We need to identify the earliest kernel that did not exhibit the bug and the first kernel that did exhibit the bug.

Can you test the following kernels and post back?

v4.4.13:
http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.4.13-xenial/

If v4.4.13 exhibits the bug, 4.4.11 should be tested next:
http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.4.11-xenial/

If v4.4.13 does NOT exhibit the bug then test v4.4.15:
http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.4.15/

Based on your test results, we can figure out which kernel to test next.

Thanks in advance!

[Joseph Salisbury (jsalisbury)]

Also, it might be good to test the latest mainline kernel to see if this bug is already fixed. If it is fixed, we can instead perform a "Reverse" bisect to identify the commit that fixes the bug.

The current mainline kernel can be downloaded from:
http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.7/

[bugproxy (bugproxy)]

Default Comment by Bridge

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2018-01-12 07:57 EDT-------
IBM External Status-> closed, Verified

[Frank Heimes (fheimes)]

got fixed with an updated release