You have been subscribed to a public bug:

==== State: Open by: nguyenp on 11 August 2017 11:03:32 ====

Contact:
=======
Paul Nguyen
nguy...@us.ibm.com

BMC:
====
bos1u1

Firmware Revision : 00.25       
Firmware Build Time : 20170807  BMC MAC address : 0c:c4:7a:f4:4d:60
PNOR Build Time : 20170729      
CPLD Version : B2.91.00 

Ubuntu 16.04.3:
===========
bos1u1p1

       ver 1.5.4.5 - OS, HTX, Firmware and Machine details

                           OS: GNU/Linux
                   OS Version: Ubuntu 16.04.3 LTS \n \l
               Kernel Version: 4.11.0-12-generic
                  HTX Version: htxubuntu-448
                    Host Name: bos1u1p1
            Machine Serial No: C819UAF32B00002 
           Machine Type/Model: 9006-12C        

root@bos1u1p1:~# dpkg -l |grep mlx
ii  libmlx4-1                              41mlnx1-OFED.4.1.0.1.0.41014         
      ppc64el      Userspace driver for Mellanox ConnectX 

InfiniBand HCAs
ii  libmlx4-1-dbg                          41mlnx1-OFED.4.1.0.1.0.41014         
      ppc64el      Debugging symbols for the libmlx4 driver
ii  libmlx4-dev                            41mlnx1-OFED.4.1.0.1.0.41014         
      ppc64el      Development files for the libmlx4 driver
ii  libmlx5-1                              41mlnx1-OFED.4.1.0.1.3.0.1.41014     
      ppc64el      Userspace driver for Mellanox ConnectX 

InfiniBand HCAs
ii  libmlx5-1-dbg                          41mlnx1-OFED.4.1.0.1.3.0.1.41014     
      ppc64el      Debugging symbols for the libmlx5 driver
ii  libmlx5-dev                            41mlnx1-OFED.4.1.0.1.3.0.1.41014     
      ppc64el      Development files for the libmlx5 driver

root@bos1u1p1:~# lsscsi
[0:2:0:0]    disk    SEAGATE  ST4000NM0034     E005  /dev/sda 
[0:3:123:0]  enclosu ADAPTEC  Smart Adapter    2.99  -        
root@bos1u1p1:~# lspci
0000:00:00.0 PCI bridge: IBM Device 04c1
0001:00:00.0 PCI bridge: IBM Device 04c1
0002:00:00.0 PCI bridge: IBM Device 04c1
0002:01:00.0 Ethernet controller: Intel Corporation Ethernet Controller 
X710/X557-AT 10GBASE-T (rev 02)
0002:01:00.1 Ethernet controller: Intel Corporation Ethernet Controller 
X710/X557-AT 10GBASE-T (rev 02)
0002:01:00.2 Ethernet controller: Intel Corporation Ethernet Controller 
X710/X557-AT 10GBASE-T (rev 02)
0002:01:00.3 Ethernet controller: Intel Corporation Ethernet Controller 
X710/X557-AT 10GBASE-T (rev 02)
0003:00:00.0 PCI bridge: IBM Device 04c1
0003:01:00.0 Serial Attached SCSI controller: Adaptec Series 8 12G SAS/PCIe 3 
(rev 01)
0004:00:00.0 PCI bridge: IBM Device 04c1
0004:01:00.0 PCI bridge: ASPEED Technology, Inc. AST1150 PCI-to-PCI Bridge (rev 
04)
0004:02:00.0 VGA compatible controller: ASPEED Technology, Inc. ASPEED Graphics 
Family (rev 41)
0005:00:00.0 PCI bridge: IBM Device 04c1
0005:01:00.0 USB controller: Texas Instruments TUSB73x0 SuperSpeed USB 3.0 xHCI 
Host Controller (rev 02)
0030:00:00.0 PCI bridge: IBM Device 04c1
0030:01:00.0 Infiniband controller: Mellanox Technologies Device 1019
0030:01:00.1 Infiniband controller: Mellanox Technologies Device 1019
0031:00:00.0 PCI bridge: IBM Device 04c1
0031:01:00.0 Ethernet controller: Intel Corporation 82599ES 10-Gigabit SFI/SFP+ 
Network Connection (rev 01)
0031:01:00.1 Ethernet controller: Intel Corporation 82599ES 10-Gigabit SFI/SFP+ 
Network Connection (rev 01)
0032:00:00.0 PCI bridge: IBM Device 04c1
0033:00:00.0 PCI bridge: IBM Device 04c1
0033:01:00.0 Ethernet controller: Intel Corporation 82575EB Gigabit Network 
Connection (rev 02)
0033:01:00.1 Ethernet controller: Intel Corporation 82575EB Gigabit Network 
Connection (rev 02)

root@bos1u1p1:~# ifconfig -a
enP2p1s0f0 Link encap:Ethernet  HWaddr ac:1f:6b:09:c0:9e  
          inet addr:9.3.20.217  Bcast:9.3.21.255  Mask:255.255.254.0
          inet6 addr: fe80::ae1f:6bff:fe09:c09e/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:62603 errors:0 dropped:0 overruns:0 frame:0
          TX packets:105 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:4784741 (4.7 MB)  TX bytes:14043 (14.0 KB)

enP2p1s0f1 Link encap:Ethernet  HWaddr ac:1f:6b:09:c0:9f  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

enP2p1s0f2 Link encap:Ethernet  HWaddr ac:1f:6b:09:c0:a0  
          inet addr:108.1.1.217  Bcast:108.1.1.255  Mask:255.255.255.0
          inet6 addr: fe80::ae1f:6bff:fe09:c0a0/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:127350969 errors:0 dropped:65 overruns:0 frame:0
          TX packets:124182822 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:186712761859 (186.7 GB)  TX bytes:181731375235 (181.7 GB)

enP2p1s0f3 Link encap:Ethernet  HWaddr ac:1f:6b:09:c0:a1  
          inet addr:108.1.2.217  Bcast:108.1.2.255  Mask:255.255.255.0
          inet6 addr: fe80::ae1f:6bff:fe09:c0a1/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:124182726 errors:0 dropped:0 overruns:0 frame:0
          TX packets:127351289 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:181731250053 (181.7 GB)  TX bytes:186713217880 (186.7 GB)

enP49p1s0f0 Link encap:Ethernet  HWaddr 0c:c4:7a:eb:17:ea  
          inet addr:104.1.1.217  Bcast:104.1.1.255  Mask:255.255.255.0
          inet6 addr: fe80::ec4:7aff:feeb:17ea/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:126415178 errors:0 dropped:0 overruns:0 frame:0
          TX packets:124809946 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:185222061670 (185.2 GB)  TX bytes:183034803740 (183.0 GB)

enP49p1s0f1 Link encap:Ethernet  HWaddr 0c:c4:7a:eb:17:eb  
          inet addr:104.1.2.217  Bcast:104.1.2.255  Mask:255.255.255.0
          inet6 addr: fe80::ec4:7aff:feeb:17eb/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:124809938 errors:0 dropped:0 overruns:0 frame:0
          TX packets:126415188 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:183034803062 (183.0 GB)  TX bytes:185222062528 (185.2 GB)

enP51p1s0f0 Link encap:Ethernet  HWaddr 0c:c4:7a:b4:28:6c  
          inet addr:105.1.1.217  Bcast:105.1.1.255  Mask:255.255.255.0
          inet6 addr: fe80::ec4:7aff:feb4:286c/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:8067390 errors:0 dropped:0 overruns:0 frame:0
          TX packets:10234208 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:8355184401 (8.3 GB)  TX bytes:13586437864 (13.5 GB)
          Memory:620c180800000-620c18081ffff 

enP51p1s0f1 Link encap:Ethernet  HWaddr 0c:c4:7a:b4:28:6d  
          inet addr:102.1.2.217  Bcast:102.1.2.255  Mask:255.255.255.0
          inet6 addr: fe80::ec4:7aff:feb4:286d/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:10234110 errors:0 dropped:0 overruns:0 frame:0
          TX packets:8067404 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:13586422574 (13.5 GB)  TX bytes:8355185459 (8.3 GB)
          Memory:620c180820000-620c18083ffff 

ib0       Link encap:UNSPEC  HWaddr 
00-00-00-86-FE-80-00-00-00-00-00-00-00-00-00-00  
          inet addr:103.1.1.217  Bcast:103.1.1.255  Mask:255.255.255.0
          inet6 addr: fe80::268a:703:a3:2a38/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:2044  Metric:1
          RX packets:24 errors:0 dropped:0 overruns:0 frame:0
          TX packets:14 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:256 
          RX bytes:2400 (2.4 KB)  TX bytes:1160 (1.1 KB)

ib1       Link encap:UNSPEC  HWaddr 
00-00-08-46-FE-80-00-00-00-00-00-00-00-00-00-00  
          inet addr:103.1.2.217  Bcast:103.1.2.255  Mask:255.255.255.0
          inet6 addr: fe80::268a:703:a3:2a39/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:2044  Metric:1
          RX packets:24 errors:0 dropped:0 overruns:0 frame:0
          TX packets:15 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:256 
          RX bytes:2400 (2.4 KB)  TX bytes:1220 (1.2 KB)

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:2173 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2173 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:349296 (349.2 KB)  TX bytes:349296 (349.2 KB)

root@bos1u1p1:~#

               HTX Device Status Summary  Current Time: 222  08/10/17  15:35:12 
Cycle Count(Min/Max)=0/183           System Start Time: 222  08/10/17  15:11:22 
Page Number(Cur/Max)=1/2
--------------------------------------------------------------------------------
            Last Update   Cycle Curr.   |             Last Update   Cycle Curr. 
ST Device   Day   Time    Count Stanza  | ST Device   Day   Time    Count Stanza
RN cache0   222 15:34:50       15    6  | RN cpu15    222 15:35:03        5    4
RN cache1   222 15:35:03       51    5  | RN enP2p1s0f222 15:35:11      183    1
RN cpu0     222 15:34:47        2    4  | RN enP2p1s0f222 15:35:11      173    1
RN cpu1     222 15:33:59        2   13  | RN enP49p1s0222 15:35:11      181    1
RN cpu2     222 15:34:05        2    8  | RN enP49p1s0222 15:35:10      177    1
RN cpu3     222 15:32:59        2   13  | RN enP51p1s0222 15:34:45        4    1
RN cpu4     222 15:34:44        2   10  | RN enP51p1s0222 15:34:46       10    1
RN cpu5     222 15:34:33        2   13  | RN fpu0     222 15:35:06        3   25
RN cpu6     222 15:35:01        2    6  | RN fpu1     222 15:34:58        4    5
RN cpu7     222 15:32:42        2   13  | RN fpu2     222 15:35:10        3   30
RN cpu8     222 15:35:08        3   10  | RN fpu3     222 15:34:59        4   19
RN cpu9     222 15:35:02        3   13  | RN fpu4     222 15:34:57        3   35
RN cpu10    222 15:35:03        5    2  | RN fpu5     222 15:35:07        4   11
RN cpu11    222 15:34:47        5    1  | RN fpu6     222 15:35:05        3   28
RN cpu12    222 15:34:53        5    2  | RN fpu7     222 15:35:09        4   19
RN cpu13    222 15:35:09        5    2  | RN fpu8     222 15:35:04        6    5
RN cpu14    222 15:35:10        5    3  | RN fpu9     222 15:35:09        6   17
RN fpu10    222 15:35:28        9    2  | RN sctu10   222 15:35:24       55    1
RN fpu11    222 15:35:29        8   41  | RN sctu11   222 15:35:28       62    4
RN fpu12    222 15:35:25        8   43  | RN sctu13   222 15:35:28       66    3
RN fpu13    222 15:35:26        8   43  | RN sctu14   222 15:35:31       59    2
RN fpu14    222 15:35:29        9    7  | RN sctu15   222 15:35:28       71    2
RN fpu15    222 15:35:28        9   10  | RN tlbie    222 15:34:48       26    2
RN mem      222 15:35:10        1    4  |
RN mlx5_0   222 15:35:22        6    1  |
RN mlx5_1   222 15:35:25        6    1  |
RN rng      222 15:35:21      196    1  |
RN sctu1    222 15:35:20       64    2  |
RN sctu2    222 15:35:25       50    4  |
RN sctu3    222 15:35:27       67    4  |
RN sctu5    222 15:35:29       70    3  |
RN sctu6    222 15:35:22       57    4  |
RN sctu7    222 15:35:23       68    4  |
RN sctu9    222 15:35:20       62    1  |

Problem Description:
====================
On my Boston LC system, I running with firmware BMC 0.25 and PNOR 0807. System 
is running with Ubuntu16.04.3

- The system was running network stress then it crashed with an
alligment exception. The system is currently in xmon debugger and is
available for developer to look.

[ 1105.304668] Unable to handle kernel paging request for unaligned access at 
address 0xc00a000000000122
[ 1105.304850] Faulting instruction address: 0xc000000000a1e6b4
1e:mon> 


1e:mon> e
cpu 0x1e: Vector: 600 (Alignment) at [c000000007f0b1c0]
    pc: c000000000a1e6b4: skb_release_data+0xd4/0x1b0
    lr: c000000000a1e82c: __kfree_skb+0x2c/0x50
    sp: c000000007f0b440
   msr: 9000000000009033
   dar: c00a000000000122
 dsisr: 8000000
  current = 0xc000001a93574400
  paca    = 0xc000000007b90e00   softe: 0        irq_happened: 0x01on 
4.11.0-12-generic (buildd@bos01-ppc64el-026) (gcc version 5.4.0 20160609 
(Ubuntu/IBM 5.4.0-6ubuntu1~16.04.4) ) #17~16.04.1-Ubuntu SMP Fri Jul 28 
13:52:51 UTC 2017 (Ubuntu 4.11.0-12.17~16.04.1-generic 4.11.12)
1e:mon> t
[c000000007f0b480] c000000000a1e82c __kfree_skb+0x2c/0x50
[c000000007f0b4b0] c000000000abd77c tcp_clean_rtx_queue+0x2cc/0xd30
[c000000007f0b5d0] c000000000ac0f68 tcp_ack+0x5a8/0xa30
[c000000007f0b710] c000000000ac3004 tcp_rcv_established+0x1b4/0x830
[c000000007f0b790] c000000000ad05d4 tcp_v4_do_rcv+0x1b4/0x2f0
[c000000007f0b7d0] c000000000ad4168 tcp_v4_rcv+0xe18/0xe50
[c000000007f0b8c0] c000000000a9e7f0 ip_local_deliver_finish+0x170/0x350
[c000000007f0b910] c000000000a9f120 ip_local_deliver+0x60/0x130
[c000000007f0b970] c000000000a9ec28 ip_rcv_finish+0x258/0x510
[c000000007f0ba00] c000000000a9f550 ip_rcv+0x360/0x470
[c000000007f0ba70] c000000000a38e5c __netif_receive_skb_core+0x97c/0xdf0
[c000000007f0bb30] c000000000a3cbc8 netif_receive_skb_internal+0x38/0xd0
[c000000007f0bb70] c000000000a3db6c napi_gro_receive+0x11c/0x1d0
[c000000007f0bbb0] c008000010430c1c i40e_clean_rx_irq+0x74c/0xb00 [i40e]
[c000000007f0bca0] c00800001043134c i40e_napi_poll+0x37c/0x8f0 [i40e]
[c000000007f0bd50] c000000000a3d47c net_rx_action+0x39c/0x4a0
[c000000007f0be50] c000000000bcdc9c __do_softirq+0x19c/0x3fc
[c000000007f0bf40] c0000000000f3748 irq_exit+0xe8/0x120
[c000000007f0bf60] c000000000016b00 __do_irq+0x90/0x1d0
[c000000007f0bf90] c00000000002a5d0 call_do_irq+0x14/0x24
[c000001a935dfde0] c000000000016ce0 do_IRQ+0xa0/0x150
[c000001a935dfe30] c000000000009b94 h_virt_irq_common+0x114/0x120
--- Exception: ea1  at 00003fff920d8ce4
SP (3fff9184e5c0) is in userspace
1e:mon> r
R00 = c000000000a1e82c   R16 = c000000007f0b678
R01 = c000000007f0b440   R17 = c000000007f0b660
R02 = c0000000014fdf00   R18 = 00000000000000694
R04 = c000001c86fad600   R20 = 0000000000000000
R05 = 00000000003417f0   R21 = 00000000001fffff
R06 = c000001d9701b2a0   R22 = c000001c7aae3d58
R07 = c000001d9701b000   R23 = ffffffffffffff92
R08 = 0000000000000280   R24 = 000000000001fe28
R09 = 000000000120c00a   R25 = 00000000f8eb2d17
R10 = c00a000000000122   R26 = 0003126941e19a70
R11 = 0003126941e19a26   R27 = 0000000000000000
R12 = 0000000039059303   R28 = 0003126941e199ed
R13 = c000000007b90e00   R29 = c000001c86fad600
R14 = c000001c7aae3c00   R30 = c000001d9701b280
R15 = c000001c86fad600   R31 = 0000000000000000
pc  = c000000000a1e6b4 skb_release_data+0xd4/0x1b0
cfar= c000000000a1e670 skb_release_data+0x90/0x1b0
lr  = c000000000a1e82c __kfree_skb+0x2c/0x50
msr = 9000000000009033   cr  = 39059305
ctr = c000000000a97200   xer = 00000000a0000000   trap =  600
dar = c00a000000000122   dsisr = 08000000
1e:mon> S
msr    = 9000000000001033  sprg0 = 000000000000091c
pvr    = 00000000004e0100  sprg1 = 0000000000000000
dec    = ffff6e56be3f98df  sprg2 = 0000000000000000
sp     = c000000007f0ac00  sprg3 = 000000000000001e
toc    = c0000000014fdf00  dar   = c00a000000000122
srr0   = 0000000000091484  srr1  = 0000000000001033 dsisr  = 08000000
dscr   = 0000000000000000  ppr   = 0000000000000000 pir    = 0000005e
sdr1   = 0000000000000000  hdar  = 0000000000000000 hdsisr = 00000000
hsrr0  = 00000000300050b0 hsrr1  = 0000000000001002 hdec = 7600c75f
lpcr   = 0000000001d2f012  pcr   = 0000000000000000 lpidr = 00000000
hsprg0 = 0000000007b90e00 hsprg1 = 0000000007b90e00
dabr   = 0000000000000000 dabrx  = 0000000000091484
dpdes  = 0000000000000000  tir   = 0000000000000002 cir    = 00000000
fscr   = 0000000000000180  tar   = 0000000000000000 pspb   = 00000000
mmcr0  = 0000000000000000  mmcr1 = 0000000000000000 mmcr2  = 0000000000000000
pmc1   = 00000000 pmc2 = 00000000  pmc3 = 00000000  pmc4   = 00000000
mmcra  = 0000000000000000   siar = 0000000000000000 pmc5   = 80000001
sdar   = 0000000000000000   sier = 0000000000000000 pmc6   = 8000000b
ebbhr  = 0000000000000000  ebbrr = 0000000000000000 bescr  = 0000000000000000
hfscr  = 000000000000059f  dhdes = 0000000000091484 rpr    = 0000000000000000
dawr   = 0000000000000000  dawrx = 000000000000fc00 ciabr  = 0000000000000000
1e:mon>

== Comment: #7 - VIPIN K. PARASHAR <vipar...@in.ibm.com> - 2017-08-14
12:50:36 ==

1e:mon> di %pc
c000000000a1e6b4  7d205028      lwarx   r9,0,r10
c000000000a1e6b8  3129ffff      addic   r9,r9,-1
c000000000a1e6bc  7d20512d      stwcx.  r9,0,r10
c000000000a1e6c0  40c2fff4      bne-    c000000000a1e6b4        # 
skb_release_data+0xd4/0x1b0
c000000000a1e6c4  7d2907b4      extsw   r9,r9
c000000000a1e6c8  7c0004ac      hwsync
c000000000a1e6cc  2fa90000      cmpdi   cr7,r9,0
c000000000a1e6d0  409effb0      bne     cr7,c000000000a1e680    # 
skb_release_data+0xa0/0x1b0
c000000000a1e6d4  4b88b495      bl      c0000000002a9b68        # 
__put_page+0x8/0x80
c000000000a1e6d8  60000000      nop
c000000000a1e6dc  893e0000      lbz     r9,0(r30)
c000000000a1e6e0  395f0001      addi    r10,r31,1
c000000000a1e6e4  7d5f07b4      extsw   r31,r10
c000000000a1e6e8  7f895000      cmpw    cr7,r9,r10
c000000000a1e6ec  419dffa8      bgt     cr7,c000000000a1e694    # 
skb_release_data+0xb4/0x1b0
c000000000a1e6f0  893e0001      lbz     r9,1(r30)
1e:mon> 

>> c000000000a1e6b4  7d205028   lwarx   r9,0,r10   <---

R10 = c00a000000000122


R10 is being used for load but it doesn't contain word aligned address.
Thus Alignment interrupt is getting triggered.

== Comment: #11 - VIPIN K. PARASHAR <vipar...@in.ibm.com> - 2017-08-14 13:12:54 
==
(In reply to comment #5)

> Before I did apt-get update and upgrade on this system, I was running with
> this level:
> 
> 4.10.0-22-generic #24~16.04.1-Ubuntu SMP Mon May 22 22:11:01 UTC 2017
> ppc64le ppc64le ppc64le GNU/Linux
> 
> With the previous level above, I did not see the problem.

Crash is being seen with kernel 4.11.0-12-generic in TCP/IP stack code 
Its likely due to some code changes introduced after >= 4.10.0-22-generic.

** Affects: linux (Ubuntu)
     Importance: Undecided
     Assignee: Ubuntu on IBM Power Systems Bug Triage (ubuntu-power-triage)
         Status: New


** Tags: architecture-ppc64le bugnameltc-157626 severity-high 
targetmilestone-inin16043
-- 
Ubuntu16.04.3: System running network stress crashes with Alignment exception
https://bugs.launchpad.net/bugs/1710690
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