Comment 0 for bug 1728098

---Problem Description---
Please backport console irq patch .

commit 00dab8187e182da41122f66c207707b192509df4
Author: Sam Mendoza-Jonas <email address hidden>
Date: Mon Jul 11 13:38:58 2016 +1000

    tty/hvc: Use opal irqchip interface if available

    Update the hvc driver to use the OPAL irqchip if made available by the
    running firmware. If it is not present, the driver falls back to the
    existing OPAL event number.

    Signed-off-by: Samuel Mendoza-Jonas <email address hidden>
    Signed-off-by: Michael Ellerman <email address hidden>

---uname output---
Linux tul217p1 4.4.0-98-generic #121-Ubuntu SMP Tue Oct 10 14:23:01 UTC 2017 ppc64le ppc64le ppc64le GNU/Linux

Machine Type = FSP based PowerNV system

Canonical,

We need this patch in 16.04 GA 4.4 kernel. This fix will avoid the following error:

Oct 19 22:15:07 tul217p1 kernel: sched: RT throttling activated
Oct 19 22:15:49 tul217p1 kernel: INFO: rcu_sched self-detected stall on CPU
Oct 19 22:15:49 tul217p1 kernel: 21-...: (85 GPs behind) idle=d29/140000000000002/0 softirq=26316/26316 fqs=4417
Oct 19 22:15:49 tul217p1 kernel: (t=5250 jiffies g=30019 c=30018 q=20591)
Oct 19 22:15:49 tul217p1 kernel: Call Trace:
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0f110] [c0000000000fcbe0] sched_show_task+0xe0/0x180 (unreliable)
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0f180] [c00000000013fcf4] rcu_dump_cpu_stacks+0xe4/0x150
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0f1d0] [c000000000145424] rcu_check_callbacks+0x6b4/0x9b0
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0f300] [c00000000014d288] update_process_times+0x58/0xa0
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0f330] [c0000000001649b8] tick_sched_handle.isra.6+0x48/0xe0
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0f370] [c000000000164ab4] tick_sched_timer+0x64/0xd0
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0f3b0] [c00000000014dd54] __hrtimer_run_queues+0x124/0x450
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0f440] [c00000000014ed7c] hrtimer_interrupt+0xec/0x2c0
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0f500] [c00000000001f5fc] __timer_interrupt+0x8c/0x290
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0f550] [c00000000001f9b0] timer_interrupt+0xa0/0xe0
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0f580] [c0000000000099d8] restore_check_irq_replay+0x54/0x70
Oct 19 22:15:49 tul217p1 kernel: --- interrupt: 901 at arch_local_irq_restore+0x74/0x90
                                     LR = arch_local_irq_restore+0x74/0x90
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0f870] [7fffffffffffffff] 0x7fffffffffffffff (unreliable)
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0f890] [c0000000000bf808] __do_softirq+0xd8/0x3e0
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0f980] [c0000000000bfd88] irq_exit+0xc8/0x100
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0f9a0] [c00000000001f9b4] timer_interrupt+0xa4/0xe0
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0f9d0] [c0000000000099d8] restore_check_irq_replay+0x54/0x70
Oct 19 22:15:49 tul217p1 kernel: --- interrupt: 901 at irq_work_queue+0x60/0xd0
                                     LR = irq_work_queue+0xa4/0xd0
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0fcc0] [c0000007f4d0fd00] 0xc0000007f4d0fd00 (unreliable)
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0fcf0] [c000000000076a98] opal_handle_events+0x108/0x130
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0fd40] [c000000000070fc8] kopald+0x78/0x100
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0fd80] [c0000000000e7374] kthread+0x124/0x150
Oct 19 22:15:49 tul217p1 kernel: [c0000007f4d0fe30] [c000000000009538] ret_from_kernel_thread+0x5c/0xa4
Oct 19 22:15:54 tul217p1 kernel: NMI watchdog: BUG: soft lockup - CPU#21 stuck for 23s! [kopald:494]
Oct 19 22:15:54 tul217p1 kernel: Modules linked in: ibmpowernv binfmt_misc ipmi_powernv ipmi_msghandler leds_powernv powernv_rng
uio_pdrv_genirq uio vmx_crypto nfsd auth_rpcgss nfs_acl lockd ib_iser grace rdma_cm iw_cm sunrpc ib_cm ib_sa ib_mad ib_core ib_
addr iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi autofs4 btrfs raid10 raid456 async_raid6_recov async_memcpy async_pq a
sync_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear ipr cxl
Oct 19 22:15:54 tul217p1 kernel: CPU: 21 PID: 494 Comm: kopald Not tainted 4.4.0-98-generic #121-Ubuntu
Oct 19 22:15:54 tul217p1 kernel: task: c0000007f4cc3f30 ti: c0000007f4d0c000 task.ti: c0000007f4d0c000
Oct 19 22:15:54 tul217p1 kernel: NIP: c000000000010964 LR: c000000000010964 CTR: c00000000001f100
Oct 19 22:15:54 tul217p1 kernel: REGS: c0000007f4d0f5f0 TRAP: 0901 Not tainted (4.4.0-98-generic)
Oct 19 22:15:54 tul217p1 kernel: MSR: 9000000000009033 <SF,HV,EE,ME,IR,DR,RI,LE> CR: 28000824 XER: 20000000
Oct 19 22:15:54 tul217p1 kernel: CFAR: c000000000009958 SOFTE: 1
                                 GPR00: c0000000000bf808 c0000007f4d0f870 c000000001608300 0000000000000900
                                 GPR04: c0000007fbd40400 0000000000000001 0000000000000018 0000000001f404db
                                 GPR08: 0000000000000000 0000000000000000 c0000007f4d0c000 0000000000000005
                                 GPR12: c00000000006e3c8 c00000000fb4c780
Oct 19 22:15:54 tul217p1 kernel: NIP [c000000000010964] arch_local_irq_restore+0x74/0x90
Oct 19 22:15:54 tul217p1 kernel: LR [c000000000010964] arch_local_irq_restore+0x74/0x90
Oct 19 22:15:54 tul217p1 kernel: Call Trace:
Oct 19 22:15:54 tul217p1 kernel: [c0000007f4d0f870] [7fffffffffffffff] 0x7fffffffffffffff (unreliable)
Oct 19 22:15:54 tul217p1 kernel: [c0000007f4d0f890] [c0000000000bf808] __do_softirq+0xd8/0x3e0
Oct 19 22:15:54 tul217p1 kernel: [c0000007f4d0f980] [c0000000000bfd88] irq_exit+0xc8/0x100
Oct 19 22:15:54 tul217p1 kernel: [c0000007f4d0f9a0] [c00000000001f9b4] timer_interrupt+0xa4/0xe0
Oct 19 22:15:54 tul217p1 kernel: [c0000007f4d0f9d0] [c0000000000099d8] restore_check_irq_replay+0x54/0x70
Oct 19 22:15:54 tul217p1 kernel: --- interrupt: 901 at irq_work_queue+0x60/0xd0
                                     LR = irq_work_queue+0xa4/0xd0
Oct 19 22:15:54 tul217p1 kernel: [c0000007f4d0fcc0] [c0000007f4d0fd00] 0xc0000007f4d0fd00 (unreliable)
Oct 19 22:15:54 tul217p1 kernel: [c0000007f4d0fcf0] [c000000000076a98] opal_handle_events+0x108/0x130
Oct 19 22:15:54 tul217p1 kernel: [c0000007f4d0fd40] [c000000000070fc8] kopald+0x78/0x100
Oct 19 22:15:54 tul217p1 kernel: [c0000007f4d0fd80] [c0000000000e7374] kthread+0x124/0x150
Oct 19 22:15:54 tul217p1 kernel: [c0000007f4d0fe30] [c000000000009538] ret_from_kernel_thread+0x5c/0xa4
Oct 19 22:15:54 tul217p1 kernel: Instruction dump:
Oct 19 22:15:54 tul217p1 kernel: 994d02ca 2fa30000 409e0024 e92d0020 61298000 7d210164 38210020 e8010010
Oct 19 22:15:54 tul217p1 kernel: 7c0803a6 4e800020 60420000 4bff186d <60000000> 4bffffe4 60420000 e92d0020
Oct 19 22:16:39 tul217p1 kernel: INFO: rcu_sched self-detected stall on CPU
Oct 19 22:16:39 tul217p1 kernel: 16-...: (301 GPs behind) idle=5b5/140000000000002/0 softirq=2284/2284 fqs=4838
Oct 19 22:16:39 tul217p1 kernel: (t=5250 jiffies g=30159 c=30158 q=20605)
Oct 19 22:16:39 tul217p1 kernel: Call Trace:
Oct 19 22:16:39 tul217p1 kernel: [c0000007f4d0f150] [c0000000000fcbe0] sched_show_task+0xe0/0x180 (unreliable)
Oct 19 22:16:39 tul217p1 kernel: [c0000007f4d0f1c0] [c00000000013fcf4] rcu_dump_cpu_stacks+0xe4/0x150
Oct 19 22:16:39 tul217p1 kernel: [c0000007f4d0f210] [c000000000145424] rcu_check_callbacks+0x6b4/0x9b0
Oct 19 22:16:39 tul217p1 kernel: [c0000007f4d0f340] [c00000000014d288] update_process_times+0x58/0xa0
Oct 19 22:16:39 tul217p1 kernel: [c0000007f4d0f370] [c0000000001649b8] tick_sched_handle.isra.6+0x48/0xe0
Oct 19 22:16:39 tul217p1 kernel: [c0000007f4d0f3b0] [c000000000164ab4] tick_sched_timer+0x64/0xd0
Oct 19 22:16:39 tul217p1 kernel: [c0000007f4d0f3f0] [c00000000014dd54] __hrtimer_run_queues+0x124/0x450
Oct 19 22:16:39 tul217p1 kernel: [c0000007f4d0f480] [c00000000014ed7c] hrtimer_interrupt+0xec/0x2c0
Oct 19 22:16:39 tul217p1 kernel: [c0000007f4d0f540] [c00000000001f5fc] __timer_interrupt+0x8c/0x290
Oct 19 22:16:39 tul217p1 kernel: [c0000007f4d0f590] [c00000000001f9b0] timer_interrupt+0xa0/0xe0
Oct 19 22:16:39 tul217p1 kernel: [c0000007f4d0f5c0] [c0000000000099d8] restore_check_irq_replay+0x54/0x70
Oct 19 22:16:39 tul217p1 kernel: --- interrupt: 901 at arch_local_irq_restore+0x74/0x90