Comment 29 for bug 1927076

Revision history for this message
Thadeu Lima de Souza Cascardo (cascardo) wrote : Re: IPv6 TCP in reuseport_bpf_cpu from ubuntu_kernel_selftests/net crash P8 node entei on 5.8 kernel (Oops: Exception in kernel mode, sig: 4 [#1])

9f:mon> di c008000013566000 1000
c008000013566000 7fe00008 trap
 ...
c008000013566eb8 60000000 nop
 ...
c008000013566ec0 7c0802a6 mflr r0
c008000013566ec4 f8010010 std r0,16(r1)
c008000013566ec8 f821ffa1 stdu r1,-96(r1)
c008000013566ecc 3d80c000 lis r12,-16384
c008000013566ed0 798c07c6 rldicr r12,r12,32,31
c008000013566ed4 658c0036 oris r12,r12,54
c008000013566ed8 618c51e0 ori r12,r12,20960
c008000013566edc 7d8903a6 mtctr r12
c008000013566ee0 4e800421 bctrl
c008000013566ee4 7c681b78 mr r8,r3
c008000013566ee8 38210060 addi r1,r1,96
c008000013566eec e8010010 ld r0,16(r1)
c008000013566ef0 7c0803a6 mtlr r0
c008000013566ef4 7d034378 mr r3,r8
c008000013566ef8 4e800020 blr
c008000013566efc 7fe00008 trap
 ...
9f:mon> r
R00 = c0000000000173d8 R16 = c000007fe13e8cb0
R01 = c0000040074efda0 R17 = c000007f8f6a0000
R02 = c0000000022d9900 R18 = c000007f8f6a0080
R03 = c0000040074efbd8 R19 = c000007f8f6a0080
R04 = 0000000000200000 R20 = c0000000012ff767
R05 = 0000000000030000 R21 = c000007f8f6a0080
R06 = 0000000000020000 R22 = c00000000136cc78
R07 = 0000000000517782 R23 = 0000000000000001
R08 = 0000001ebf7e3a55 R24 = 000000000000009f
R09 = 0000000000000000 R25 = 0000000000000e60
R10 = 0000000000000001 R26 = 0000000000000900
R11 = 0000000000000f8e R27 = 0000000000000500
R12 = 0000000000004400 R28 = 0000000000000a00
R13 = c000007fff6f4f80 R29 = 0000000000000f00
R14 = 0000000000000000 R30 = 0000000000000002
R15 = c0000000012f6020 R31 = 0000000000000003
pc = c000000000017038 replay_soft_interrupts+0x68/0x2e0
cfar= 0000000000000000
lr = c0000000000173d8 arch_local_irq_restore+0x128/0x160
msr = 9000000000001033 cr = 24004428
ctr = c000000000042468 xer = 0000000020000000 trap = 500
9f:mon> c0
[link register ] c000000000f36d4c __bpf_prog_run_save_cb+0x5c/0x190
[c000003ffffa3780] c000000000fdf76c __ip_finish_output+0x8c/0x140 (unreliable)
[c000003ffffa37f0] c000000000f36f2c run_bpf_filter+0xac/0x200
[c000003ffffa3850] c000000000f37104 reuseport_select_sock+0x84/0x170
[c000003ffffa3890] c00000000112c1f8 inet6_lhash2_lookup+0x1c8/0x200
[c000003ffffa3910] c00000000112c48c inet6_lookup_listener+0x25c/0x280
[c000003ffffa3a00] c000000001105e58 tcp_v6_rcv+0x7b8/0xf50
[c000003ffffa3b50] c0000000010b79c0 ip6_protocol_deliver_rcu+0x110/0x630
[c000003ffffa3bc0] c0000000010b803c ip6_input+0x10c/0x130
[c000003ffffa3c40] c0000000010b76c4 ipv6_rcv+0x194/0x1c0
[c000003ffffa3cc0] c000000000ef68f4 __netif_receive_skb_one_core+0x74/0xb0
[c000003ffffa3d10] c000000000ef6d68 process_backlog+0x138/0x280
[c000003ffffa3d80] c000000000ef7e00 napi_poll+0x100/0x3c0
[c000003ffffa3e10] c000000000ef81b4 net_rx_action+0xf4/0x2d0
[c000003ffffa3ea0] c0000000011815f0 __do_softirq+0x150/0x428
[c000003ffffa3f90] c00000000002caec call_do_softirq+0x14/0x24
[c000000008fcf630] c000000000017448 do_softirq_own_stack+0x38/0x50
[c000000008fcf650] c0000000001640a0 do_softirq+0xa0/0xb0
[c000000008fcf680] c0000000001641a8 __local_bh_enable_ip+0xf8/0x120
[c000000008fcf6a0] c0000000010b1a98 ip6_finish_output2+0x248/0x7c0
[c000000008fcf740] c0000000010b1410 ip6_xmit+0x370/0x7b0
[c000000008fcf860] c00000000110f7f4 inet6_csk_xmit+0xb4/0x130
[c000000008fcf900] c00000000100e910 __tcp_transmit_skb+0x440/0x9f0
[c000000008fcfa10] c00000000100f758 tcp_connect+0x2e8/0x390
[c000000008fcfae0] c0000000011023e4 tcp_v6_connect+0x5e4/0x7b0
[c000000008fcfbd0] c000000001042e10 __inet_stream_connect+0x130/0x3a0
[c000000008fcfc30] c0000000010430dc inet_stream_connect+0x5c/0x90
[c000000008fcfc70] c000000000eb8e58 __sys_connect_file+0xa8/0xe0
[c000000008fcfcb0] c000000000eb8f74 __sys_connect+0xe4/0x140
[c000000008fcfd90] c000000000eb8ff8 sys_connect+0x28/0x40
[c000000008fcfdb0] c000000000036fe4 system_call_exception+0xf4/0x200
[c000000008fcfe10] c00000000000d860 system_call_common+0xf0/0x27c
--- Exception: c00 (System Call) at 00007cf993a78388
SP (7ffff12cb970) is in userspace
0:mon> r
R00 = c000000000f36f2c R16 = 000000000000ada3
R01 = c000003ffffa3780 R17 = 000000000000000a
R02 = c0000000022d9900 R18 = 0000000000000001
R03 = c000000037c930e0 R19 = 0000000000000001
R04 = c008000013110038 R20 = c0000040213f4d48
R05 = c008000013110000 R21 = 0000000000000000
R06 = c000000037c930e0 R22 = 00000000000022b9
R07 = 0000000000000001 R23 = 0000000000000001
R08 = 0000000000000001 R24 = 000000000000ada3
R09 = 0000000000000000 R25 = c008000013110000
R10 = c00000011c2edf00 R26 = 0000000000000000
R11 = 0000000000000000 R27 = 00000000000000a0
R12 = c008000013566eb8 R28 = c000000037c930e0
R13 = c000000002590000 R29 = 0000000000000028
R14 = c0000000021fa500 R30 = 0000000000000028
R15 = 00000000000022b9 R31 = c008000013110000
pc = c008000013566eb8
cfar= c000000000f36d48 __bpf_prog_run_save_cb+0x58/0x190
lr = c000000000f36d4c __bpf_prog_run_save_cb+0x5c/0x190
msr = 9000000000029033 cr = 28002882
ctr = c008000013566eb8 xer = 0000000020000000 trap = 700
0:mon> di c008000013566000 1000
c008000013566000 7fe00008 trap
 ...
0:mon> di c008000013560000 10000
c008000013560000 00000001 .long 0x1
c008000013560004 7fe00008 trap
 ...
c008000013562728 60000000 nop
 ...
c008000013562730 7c0802a6 mflr r0
c008000013562734 f8010010 std r0,16(r1)
c008000013562738 f821ffa1 stdu r1,-96(r1)
c00800001356273c 3d80c000 lis r12,-16384
c008000013562740 798c07c6 rldicr r12,r12,32,31
c008000013562744 658c0036 oris r12,r12,54
c008000013562748 618c51e0 ori r12,r12,20960
c00800001356274c 7d8903a6 mtctr r12
c008000013562750 4e800421 bctrl
c008000013562754 7c681b78 mr r8,r3
c008000013562758 38210060 addi r1,r1,96
c00800001356275c e8010010 ld r0,16(r1)
c008000013562760 7c0803a6 mtlr r0
c008000013562764 7d034378 mr r3,r8
c008000013562768 4e800020 blr
c00800001356276c 7fe00008 trap
 ...
0:mon>