+ Jens and linux-kernel
On 2021/06/09 15:53, Shinichiro Kawasaki wrote:
> Hi there,
>
> Let me share a blktests failure. When I ran blktests on the kernel v5.13-rc5,
> block/008 failed. A WARNING below was the cause of the failure.
>
> WARNING: CPU: 1 PID: 135817 at kernel/sched/core.c:3175 ttwu_queue_wakelist+0x284/0x2f0
>
> I'm trying to recreate the failure repeating the test case, but so far, I am not
> able to. This failure looks rare, but actually, I observed it 3 times in the
> past one year.
>
> 1) Oct/2020, kernel: v5.9-rc7 test dev: dm-flakey on AHCI-SATA SMR HDD, log [1]
> 2) Mar/2021, kernel: v5.12-rc2 test dev: AHCI-SATA SMR HDD, log [2]
> 3) Jun/2021, kernel: v5.13-rc5 test dev: dm-linear on null_blk zoned, log [3]
>
> The test case block/008 does IO during CPU hotplug, and the WARNING in
> ttwu_queue_wakelist() checks "WARN_ON_ONCE(cpu == smp_processor_id())".
> So it is likely that the test case triggers the warning, but I don't have
> clear view why and how the warning was triggered. It was observed on various
> block devices, so I would like to ask linux-block experts if anyone can tell
> what is going on. Comments will be appreciated.
>
>
> [1]
>
> [29603.810633][T127266] ------------[ cut here ]------------
> [29603.816381][T127266] WARNING: CPU: 4 PID: 127266 at kernel/sched/core.c:2670 ttwu_queue_wakelist+0x27c/0x2b0
> [29603.826198][T127266] Modules linked in: dm_flakey iscsi_target_mod tcm_loop target_core_pscsi target_core_file target_core_iblock xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nf_nat_tftp nf_conntrack_tftp tun bridge stp llc nft_objref nf_conntrack_netbios_ns nf_conntrack_broadcast nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_tables ebtable_nat ebtable_broute ip6table_nat ip6table_mangle ip6table_raw ip6table_security iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 libcrc32c iptable_mangle iptable_raw iptable_security target_core_user rfkill target_core_mod ip_set nfnetlink ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter sunrpc intel_rapl_msr iTCO_wdt iTCO_vendor_support intel_rapl_common x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass intel_cstate intel_uncore joydev pcspkr i2c_i801 i2c_smbus mei_me mei lpc_ich ses enclosure ioatdma wmi
> [29603.826259][T127266] ipmi_ssif ipmi_si ipmi_devintf ipmi_msghandler acpi_power_meter acpi_pad ip_tables drm_vram_helper drm_kms_helper crct10dif_pclmul drm_ttm_helper crc32_pclmul ttm crc32c_intel drm ghash_clmulni_intel igb mpt3sas nvme dca nvme_core i2c_algo_bit raid_class scsi_transport_sas fuse [last unloaded: null_blk]
> [29603.941330][T127266] CPU: 4 PID: 127266 Comm: fio Not tainted 5.9.0-rc7 #1
> [29603.948201][T127266] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
> [29603.956368][T127266] RIP: 0010:ttwu_queue_wakelist+0x27c/0x2b0
> [29603.962198][T127266] Code: 89 e7 e8 37 5d 60 00 e9 2c fe ff ff e8 3d 5d 60 00 e9 f0 fd ff ff e8 53 5d 60 00 e9 41 ff ff ff e8 89 5d 60 00 e9 7b ff ff ff <0f> 0b e9 a6 fe ff ff 48 89 04 24 e8 04 5d 60 00 48 8b 04 24 e9 8e
> [29603.981715][T127266] RSP: 0018:ffff88856b3ef3f0 EFLAGS: 00010046
> [29603.987714][T127266] RAX: 0000000000000004 RBX: ffff88861ad21200 RCX: ffff88861ad00000
> [29603.995616][T127266] RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff98dfe920
> [29604.003521][T127266] RBP: 0000000000000000 R08: 0000000000000004 R09: ffffffff9988a227
> [29604.011425][T127266] R10: fffffbfff3311444 R11: 0000000000000001 R12: 0000000000000004
> [29604.019330][T127266] R13: ffff8886035b8000 R14: 0000000000000004 R15: ffffffff98dfe920
> [29604.027235][T127266] FS: 00007f43b1067a40(0000) GS:ffff88861ad00000(0000) knlGS:0000000000000000
> [29604.036099][T127266] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [29604.042618][T127266] CR2: 00007f2a8eeeb421 CR3: 000000057abf2001 CR4: 00000000001706e0
> [29604.050523][T127266] Call Trace:
> [29604.053757][T127266] ? lock_is_held_type+0xbb/0xf0
> [29604.058640][T127266] ? rcu_read_lock_sched_held+0x3f/0x80
> [29604.064123][T127266] try_to_wake_up+0x4f0/0x1420
> [29604.068831][T127266] ? migrate_swap_stop+0x970/0x970
> [29604.073882][T127266] ? insert_work+0x18b/0x2d0
> [29604.078417][T127266] __queue_work+0x4f2/0xe90
> [29604.082863][T127266] ? try_to_grab_pending.part.0+0x23/0x530
> [29604.088604][T127266] ? lockdep_hardirqs_off+0x80/0xb0
> [29604.093738][T127266] mod_delayed_work_on+0x9a/0x110
> [29604.098703][T127266] ? cancel_delayed_work_sync+0x10/0x10
> [29604.104182][T127266] ? __blk_mq_delay_run_hw_queue+0x95/0x570
> [29604.110019][T127266] kblockd_mod_delayed_work_on+0x17/0x20
> [29604.115586][T127266] blk_mq_run_hw_queue+0x125/0x270
> [29604.120630][T127266] ? blk_mq_delay_run_hw_queues+0x150/0x150
> [29604.126459][T127266] blk_mq_sched_insert_request+0x2d4/0x5f0
> [29604.132201][T127266] ? __blk_mq_sched_bio_merge+0x440/0x440
> [29604.137863][T127266] blk_mq_submit_bio+0xaa4/0x14e0
> [29604.142828][T127266] ? blk_mq_try_issue_directly+0x120/0x120
> [29604.148577][T127266] ? percpu_ref_put_many.constprop.0+0x83/0x150
> [29604.154757][T127266] ? dm_wq_work+0x210/0x210
> [29604.159201][T127266] submit_bio_noacct+0x6b9/0xc30
> [29604.164078][T127266] ? lock_is_held_type+0xbb/0xf0
> [29604.168960][T127266] ? bio_associate_blkg_from_css+0x1c6/0xb00
> [29604.174877][T127266] ? blk_queue_enter+0x7c0/0x7c0
> [29604.179762][T127266] submit_bio+0xe4/0x480
> [29604.183943][T127266] ? submit_bio_noacct+0xc30/0xc30
> [29604.188999][T127266] ? bio_add_pc_page+0xd0/0xd0
> [29604.193702][T127266] ? bio_release_pages.part.0+0x10c/0x3d0
> [29604.199367][T127266] __blkdev_direct_IO_simple+0x41f/0x7a0
> [29604.204938][T127266] ? bd_link_disk_holder+0x780/0x780
> [29604.210160][T127266] ? mark_lock+0x82/0x1470
> [29604.214522][T127266] ? __lock_acquire+0xb66/0x5400
> [29604.219400][T127266] ? bd_may_claim+0xc0/0xc0
> [29604.223847][T127266] ? __lock_acquire+0x1603/0x5400
> [29604.228811][T127266] blkdev_direct_IO+0xd6a/0x1070
> [29604.233690][T127266] ? mark_lock+0x82/0x1470
> [29604.238053][T127266] ? __lock_acquire+0x1603/0x5400
> [29604.243016][T127266] ? bd_prepare_to_claim+0x220/0x220
> [29604.248247][T127266] ? lockdep_hardirqs_on_prepare+0x4f0/0x4f0
> [29604.254164][T127266] generic_file_read_iter+0x1f4/0x470
> [29604.259477][T127266] new_sync_read+0x350/0x5d0
> [29604.264007][T127266] ? vfs_dedupe_file_range+0x5c0/0x5c0
> [29604.269414][T127266] ? inode_security+0x56/0xf0
> [29604.274032][T127266] vfs_read+0x296/0x4a0
> [29604.278126][T127266] __x64_sys_pread64+0x17d/0x1d0
> [29604.283004][T127266] ? vfs_read+0x4a0/0x4a0
> [29604.287271][T127266] ? trace_hardirqs_on+0x20/0x170
> [29604.292238][T127266] do_syscall_64+0x33/0x40
> [29604.296593][T127266] entry_SYSCALL_64_after_hwframe+0x44/0xa9
> [29604.302421][T127266] RIP: 0033:0x7f43baf6924f
> [29604.306778][T127266] Code: 08 89 3c 24 48 89 4c 24 18 e8 ed f3 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 48 8b 74 24 08 8b 3c 24 b8 11 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 04 24 e8 1d f4 ff ff 48 8b
> [29604.326303][T127266] RSP: 002b:00007ffec6c62e60 EFLAGS: 00000293 ORIG_RAX: 0000000000000011
> [29604.334648][T127266] RAX: ffffffffffffffda RBX: 00000000011fc540 RCX: 00007f43baf6924f
> [29604.342554][T127266] RDX: 0000000000001000 RSI: 00000000012ac000 RDI: 0000000000000008
> [29604.350459][T127266] RBP: 00000000011fc540 R08: 0000000000000000 R09: 00007ffec6d7b1b0
> [29604.358370][T127266] R10: 0000000001936000 R11: 0000000000000293 R12: 00007f43576f4d20
> [29604.366276][T127266] R13: 0000000000000000 R14: 0000000000001000 R15: 00000000011fc568
> [29604.374188][T127266] irq event stamp: 78824
> [29604.378368][T127266] hardirqs last enabled at (78823): [<ffffffff963c4550>] ktime_get+0x150/0x190
> [29604.387318][T127266] hardirqs last disabled at (78824): [<ffffffff96239567>] mod_delayed_work_on+0xd7/0x110
> [29604.397045][T127266] softirqs last enabled at (78564): [<ffffffff98201092>] asm_call_irq_on_stack+0x12/0x20
> [29604.406861][T127266] softirqs last disabled at (78555): [<ffffffff98201092>] asm_call_irq_on_stack+0x12/0x20
> [29604.416673][T127266] ---[ end trace effce0b470837a17 ]---
> [29604.422074][ C4]
> [29604.422075][ C4] ======================================================
> [29604.422076][ C4] WARNING: possible circular locking dependency detected
> [29604.422077][ C4] 5.9.0-rc7 #1 Not tainted
> [29604.422078][ C4] ------------------------------------------------------
> [29604.422079][ C4] fio/127266 is trying to acquire lock:
> [29604.422079][ C4] ffffffff9913a678 ((console_sem).lock){-.-.}-{2:2}, at: down_trylock+0x13/0x70
> [29604.422083][ C4]
> [29604.422083][ C4] but task is already holding lock:
> [29604.422084][ C4] ffff8886035b8c38 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0x84/0x1420
> [29604.422087][ C4]
> [29604.422088][ C4] which lock already depends on the new lock.
> [29604.422088][ C4]
> [29604.422089][ C4]
> [29604.422090][ C4] the existing dependency chain (in reverse order) is:
> [29604.422090][ C4]
> [29604.422091][ C4] -> #1 (&p->pi_lock){-.-.}-{2:2}:
> [29604.422094][ C4] _raw_spin_lock_irqsave+0x48/0x60
> [29604.422095][ C4] try_to_wake_up+0x84/0x1420
> [29604.422095][ C4] up+0x7a/0xb0
> [29604.422096][ C4] __up_console_sem+0x3c/0x70
> [29604.422097][ C4] console_unlock+0x451/0xa10
> [29604.422098][ C4] vprintk_emit+0x232/0x510
> [29604.422099][ C4] devkmsg_emit.constprop.0+0x97/0xb3
> [29604.422100][ C4] devkmsg_write.cold+0x48/0x74
> [29604.422101][ C4] do_iter_readv_writev+0x34c/0x6d0
> [29604.422102][ C4] do_iter_write+0x137/0x5d0
> [29604.422102][ C4] vfs_writev+0x14a/0x280
> [29604.422103][ C4] do_writev+0x100/0x260
> [29604.422104][ C4] do_syscall_64+0x33/0x40
> [29604.422105][ C4] entry_SYSCALL_64_after_hwframe+0x44/0xa9
> [29604.422106][ C4]
> [29604.422106][ C4] -> #0 ((console_sem).lock){-.-.}-{2:2}:
> [29604.422110][ C4] __lock_acquire+0x29e4/0x5400
> [29604.422111][ C4] lock_acquire+0x18f/0x990
> [29604.422112][ C4] _raw_spin_lock_irqsave+0x48/0x60
> [29604.422113][ C4] down_trylock+0x13/0x70
> [29604.422114][ C4] __down_trylock_console_sem+0x33/0xb0
> [29604.422115][ C4] vprintk_emit+0x203/0x510
> [29604.422115][ C4] printk+0x96/0xb2
> [29604.422116][ C4] report_bug.cold+0x31/0x5e
> [29604.422117][ C4] handle_bug+0x3d/0xa0
> [29604.422118][ C4] exc_invalid_op+0x14/0x40
> [29604.422119][ C4] asm_exc_invalid_op+0x12/0x20
> [29604.422120][ C4] ttwu_queue_wakelist+0x27c/0x2b0
> [29604.422121][ C4] try_to_wake_up+0x4f0/0x1420
> [29604.422122][ C4] __queue_work+0x4f2/0xe90
> [29604.422122][ C4] mod_delayed_work_on+0x9a/0x110
> [29604.422124][ C4] kblockd_mod_delayed_work_on+0x17/0x20
> [29604.422124][ C4] blk_mq_run_hw_queue+0x125/0x270
> [29604.422125][ C4] blk_mq_sched_insert_request+0x2d4/0x5f0
> [29604.422126][ C4] blk_mq_submit_bio+0xaa4/0x14e0
> [29604.422127][ C4] submit_bio_noacct+0x6b9/0xc30
> [29604.422128][ C4] submit_bio+0xe4/0x480
> [29604.422129][ C4] __blkdev_direct_IO_simple+0x41f/0x7a0
> [29604.422130][ C4] blkdev_direct_IO+0xd6a/0x1070
> [29604.422131][ C4] generic_file_read_iter+0x1f4/0x470
> [29604.422132][ C4] new_sync_read+0x350/0x5d0
> [29604.422133][ C4] vfs_read+0x296/0x4a0
> [29604.422134][ C4] __x64_sys_pread64+0x17d/0x1d0
> [29604.422135][ C4] do_syscall_64+0x33/0x40
> [29604.422135][ C4] entry_SYSCALL_64_after_hwframe+0x44/0xa9
> [29604.422136][ C4]
> [29604.422137][ C4] other info that might help us debug this:
> [29604.422138][ C4]
> [29604.422139][ C4] Possible unsafe locking scenario:
> [29604.422139][ C4]
> [29604.422140][ C4] CPU0 CPU1
> [29604.422141][ C4] ---- ----
> [29604.422142][ C4] lock(&p->pi_lock);
> [29604.422144][ C4] lock((console_sem).lock);
> [29604.422146][ C4] lock(&p->pi_lock);
> [29604.422148][ C4] lock((console_sem).lock);
> [29604.422149][ C4]
> [29604.422150][ C4] *** DEADLOCK ***
> [29604.422151][ C4]
> [29604.422152][ C4] 3 locks held by fio/127266:
> [29604.422152][ C4] #0: ffffffff99159260 (rcu_read_lock){....}-{1:2}, at: __queue_work+0xa0/0xe90
> [29604.422156][ C4] #1: ffff88861ad33a58 (&pool->lock){-.-.}-{2:2}, at: __queue_work+0x2d3/0xe90
> [29604.422159][ C4] #2: ffff8886035b8c38 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0x84/0x1420
> [29604.422163][ C4]
> [29604.422164][ C4] stack backtrace:
> [29604.422165][ C4] CPU: 4 PID: 127266 Comm: fio Not tainted 5.9.0-rc7 #1
> [29604.422166][ C4] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
> [29604.422167][ C4] Call Trace:
> [29604.422168][ C4] dump_stack+0xae/0xe8
> [29604.422169][ C4] check_noncircular+0x2fc/0x3b0
> [29604.422169][ C4] ? print_circular_bug+0x370/0x370
> [29604.422170][ C4] ? stack_trace_save+0x81/0xa0
> [29604.422171][ C4] ? lock_repin_lock+0x370/0x370
> [29604.422172][ C4] __lock_acquire+0x29e4/0x5400
> [29604.422173][ C4] ? lockdep_hardirqs_on_prepare+0x4f0/0x4f0
> [29604.422174][ C4] lock_acquire+0x18f/0x990
> [29604.422174][ C4] ? down_trylock+0x13/0x70
> [29604.422175][ C4] ? sched_clock_cpu+0x18/0x170
> [29604.422176][ C4] ? lock_release+0x7c0/0x7c0
> [29604.422177][ C4] ? find_held_lock+0x2c/0x110
> [29604.422178][ C4] ? vprintk_emit+0x1ba/0x510
> [29604.422179][ C4] _raw_spin_lock_irqsave+0x48/0x60
> [29604.422179][ C4] ? down_trylock+0x13/0x70
> [29604.422180][ C4] down_trylock+0x13/0x70
> [29604.422181][ C4] ? printk+0x96/0xb2
> [29604.422182][ C4] __down_trylock_console_sem+0x33/0xb0
> [29604.422183][ C4] vprintk_emit+0x203/0x510
> [29604.422183][ C4] ? ttwu_queue_wakelist+0x27c/0x2b0
> [29604.422184][ C4] printk+0x96/0xb2
> [29604.422185][ C4] ? log_store.cold+0x11/0x11
> [29604.422187][ C4] ? mark_lock+0x82/0x1470
> [29604.422188][ C4] report_bug.cold+0x31/0x5e
> [29604.422189][ C4] handle_bug+0x3d/0xa0
> [29604.422190][ C4] ? lock_acquire+0x18f/0x990
> [29604.422191][ C4] exc_invalid_op+0x14/0x40
> [29604.422191][ C4] asm_exc_invalid_op+0x12/0x20
> [29604.422192][ C4] RIP: 0010:ttwu_queue_wakelist+0x27c/0x2b0
> [29604.422193][ C4] Code: 89 e7 e8 37 5d 60 00 e9 2c fe ff ff e8 3d 5d 60 00 e9 f0 fd ff ff e8 53 5d 60 00 e9 41 ff ff ff e8 89 5d 60 00 e9 7b ff ff ff <0f> 0b e9 a6 fe ff ff 48 89 04 24 e8 04 5d 60 00 48 8b 04 24 e9 8e
> [29604.422194][ C4] RSP: 0018:ffff88856b3ef3f0 EFLAGS: 00010046
> [29604.422195][ C4] RAX: 000000000
> [29604.422197][ C4] Lost 62 message(s)!
>
>
> [2]
>
> [ 8339.653610][ C2] ------------[ cut here ]------------
> [ 8339.659324][ C2] WARNING: CPU: 2 PID: 558 at kernel/sched/core.c:3158 ttwu_queue_wakelist+0x284/0x2f0
> [ 8339.668804][ C2] Modules linked in: iscsi_target_mod tcm_loop target_core_pscsi target_core_file target_core_iblock nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat ip6table_nat ip6table_mangle ip6table_raw ip6table_security iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 iptable_mangle iptable_raw iptable_security ip_set nf_tables bridge stp llc nfnetlink rfkill target_core_user ip6table_filter target_core_mod ip6_tables iptable_filter sunrpc intel_rapl_msr intel_rapl_common x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass iTCO_wdt rapl intel_pmc_bxt iTCO_vendor_support intel_cstate joydev mei_me ses i2c_i801 mei intel_uncore enclosure ipmi_ssif lpc_ich i2c_smbus ioatdma wmi acpi_ipmi ipmi_si ipmi_devintf ipmi_msghandler acpi_power_meter acpi_pad zram ip_tables ast drm_vram_helper drm_kms_helper crc32c_intel syscopyarea sysfillrect sysimgblt fb_sys_fops cec
> [ 8339.668927][ C2] drm_ttm_helper ttm ghash_clmulni_intel drm mpt3sas igb raid_class scsi_transport_sas nvme dca nvme_core i2c_algo_bit pkcs8_key_parser [last unloaded: zonefs]
> [ 8339.770658][ C2] CPU: 2 PID: 558 Comm: systemd-udevd Not tainted 5.12.0-rc2+ #1
> [ 8339.778222][ C2] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 3.2 11/22/2019
> [ 8339.786310][ C2] RIP: 0010:ttwu_queue_wakelist+0x284/0x2f0
> [ 8339.792054][ C2] Code: 34 24 e8 3f 7d 63 00 4c 8b 44 24 10 48 8b 4c 24 08 8b 34 24 e9 a1 fe ff ff e8 78 7d 63 00 e9 66 ff ff ff e8 8e 7d 63 00 eb a0 <0f> 0b 45 31 ff e9 cb fe ff ff 48 89 04 24 e8 19 7d 63 00 48 8b 04
> [ 8339.811494][ C2] RSP: 0000:ffff888811489ce0 EFLAGS: 00010046
> [ 8339.817415][ C2] RAX: 0000000000000002 RBX: ffff88810eee3240 RCX: ffff888811480000
> [ 8339.825240][ C2] RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffffffff91e2c6f0
> [ 8339.833067][ C2] RBP: 0000000000000002 R08: ffffffff91e2c6f0 R09: ffffffff929a2ba7
> [ 8339.840894][ C2] R10: fffffbfff2534574 R11: 0000000000000001 R12: 0000000000000000
> [ 8339.848719][ C2] R13: ffff88881149f8c0 R14: 0000000000000002 R15: 0000000000032c01
> [ 8339.856545][ C2] FS: 00007fe9e16cc380(0000) GS:ffff888811480000(0000) knlGS:0000000000000000
> [ 8339.865325][ C2] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [ 8339.871763][ C2] CR2: 000055d9e787ea88 CR3: 000000011d906004 CR4: 00000000001706e0
> [ 8339.879591][ C2] Call Trace:
> [ 8339.882730][ C2] <IRQ>
> [ 8339.885440][ C2] ? lock_is_held_type+0x98/0x110
> [ 8339.890321][ C2] try_to_wake_up+0x5c7/0x1780
> [ 8339.894940][ C2] ? migrate_swap_stop+0x970/0x970
> [ 8339.899907][ C2] blk_update_request+0x711/0xe50
> [ 8339.904787][ C2] ? scsi_cleanup_rq+0x110/0x180
> [ 8339.909578][ C2] scsi_end_request+0x71/0x620
> [ 8339.914199][ C2] scsi_io_completion+0x176/0xe00
> [ 8339.919078][ C2] ? provisioning_mode_store+0x3f0/0x3f0
> [ 8339.924562][ C2] ? scsi_run_host_queues+0x60/0x60
> [ 8339.929616][ C2] blk_complete_reqs+0x9a/0xd0
> [ 8339.934235][ C2] __do_softirq+0x1d0/0x881
> [ 8339.938596][ C2] __irq_exit_rcu+0x1b9/0x270
> [ 8339.943137][ C2] irq_exit_rcu+0xa/0x20
> [ 8339.947235][ C2] sysvec_call_function_single+0x6f/0x90
> [ 8339.952721][ C2] </IRQ>
> [ 8339.955520][ C2] asm_sysvec_call_function_single+0x12/0x20
> [ 8339.961353][ C2] RIP: 0010:ptep_clear_flush+0x4f/0x150
> [ 8339.966753][ C2] Code: 48 89 f5 48 c1 ea 03 53 80 3c 02 00 0f 85 00 01 00 00 be 08 00 00 00 4c 89 ef 49 8b 5f 40 45 31 f6 e8 85 64 0a 00 4d 87 75 00 <48> c7 c0 78 cf e3 91 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80
> [ 8339.986193][ C2] RSP: 0000:ffff88811faf7ba0 EFLAGS: 00000246
> [ 8339.992111][ C2] RAX: 0000000000000001 RBX: ffff888118eb9c00 RCX: ffffffff8f7c368b
> [ 8339.999939][ C2] RDX: ffffed102446ac7f RSI: 0000000000000008 RDI: ffff8881223563f0
> [ 8340.007764][ C2] RBP: 000055d9e787e000 R08: 0000000000000001 R09: ffff8881223563f7
> [ 8340.015589][ C2] R10: ffffed102446ac7e R11: 0000000000000001 R12: ffff888121105a08
> [ 8340.023417][ C2] R13: ffff8881223563f0 R14: 8000000213aa9865 R15: ffff8881211059c8
> [ 8340.031246][ C2] ? ptep_clear_flush+0x4b/0x150
> [ 8340.036037][ C2] wp_page_copy+0x839/0x1fd0
> [ 8340.040485][ C2] ? lock_release+0x680/0x680
> [ 8340.045015][ C2] ? __do_fault+0x5d0/0x5d0
> [ 8340.049376][ C2] ? do_wp_page+0x318/0x1650
> [ 8340.053822][ C2] __handle_mm_fault+0x1f31/0x4af0
> [ 8340.058787][ C2] ? lock_is_held_type+0x98/0x110
> [ 8340.063666][ C2] ? copy_page_range+0x3810/0x3810
> [ 8340.068635][ C2] ? count_memcg_event_mm.part.0+0xfc/0x1a0
> [ 8340.074377][ C2] ? trace_hardirqs_on+0x1c/0x110
> [ 8340.079257][ C2] handle_mm_fault+0x15f/0x620
> [ 8340.083879][ C2] do_user_addr_fault+0x385/0xe30
> [ 8340.088758][ C2] ? do_kern_addr_fault+0xb0/0xb0
> [ 8340.093636][ C2] ? irqentry_enter+0x55/0x60
> [ 8340.098170][ C2] exc_page_fault+0x60/0xe0
> [ 8340.102528][ C2] ? asm_exc_page_fault+0x8/0x30
> [ 8340.107321][ C2] asm_exc_page_fault+0x1e/0x30
> [ 8340.112027][ C2] RIP: 0033:0x7fe9e25c5cdd
> [ 8340.116301][ C2] Code: 08 48 8b 4f 08 48 89 c8 48 83 e0 f8 48 3b 04 07 0f 85 91 00 00 00 48 8b 47 10 48 8b 57 18 48 3b 78 18 75 69 48 3b 7a 10 75 63 <48> 89 50 18 48 89 42 10 48 81 f9 ff 03 00 00 76 2c 48 8b 57 20 48
> [ 8340.135739][ C2] RSP: 002b:00007fff57b878d0 EFLAGS: 00010246
> [ 8340.141658][ C2] RAX: 000055d9e787ea70 RBX: 000055d9e78851d0 RCX: 0000000000000291
> [ 8340.149485][ C2] RDX: 00007fe9e2701ce0 RSI: 0000000000000002 RDI: 000055d9e78851d0
> [ 8340.157310][ C2] RBP: 00000000000002c0 R08: 000055d9e789cc70 R09: 0000000000000290
> [ 8340.165137][ C2] R10: 0000000000000047 R11: 000055d9e780d130 R12: 00007fe9e2701a00
> [ 8340.172963][ C2] R13: 00007fe9e2701a18 R14: 000000055d9e7885 R15: 000055d9e7885490
> [ 8340.180794][ C2] irq event stamp: 13527209
> [ 8340.185149][ C2] hardirqs last enabled at (13527208): [<ffffffff91400185>] __do_softirq+0x185/0x881
> [ 8340.194536][ C2] hardirqs last disabled at (13527209): [<ffffffff911e2c30>] _raw_spin_lock_irqsave+0x50/0x60
> [ 8340.204616][ C2] softirqs last enabled at (13527014): [<ffffffff8f1af839>] __irq_exit_rcu+0x1b9/0x270
> [ 8340.214175][ C2] softirqs last disabled at (13527207): [<ffffffff8f1af839>] __irq_exit_rcu+0x1b9/0x270
> [ 8340.223735][ C2] ---[ end trace b4a0f179ac6a8cbe ]---
> [ 8340.229054][ C2]
> [ 8340.229056][ C2] ======================================================
> [ 8340.229057][ C2] WARNING: possible circular locking dependency detected
> [ 8340.229058][ C2] 5.12.0-rc2+ #1 Not tainted
> [ 8340.229059][ C2] ------------------------------------------------------
> [ 8340.229059][ C2] systemd-udevd/558 is trying to acquire lock:
> [ 8340.229060][ C2] ffffffff92218b18 ((console_sem).lock){-.-.}-{2:2}, at: down_trylock+0x13/0x70
> [ 8340.229064][ C2]
> [ 8340.229065][ C2] but task is already holding lock:
> [ 8340.229065][ C2] ffff88810eee3f20 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0x88/0x1780
> [ 8340.229068][ C2]
> [ 8340.229069][ C2] which lock already depends on the new lock.
> [ 8340.229069][ C2]
> [ 8340.229070][ C2]
> [ 8340.229071][ C2] the existing dependency chain (in reverse order) is:
> [ 8340.229071][ C2]
> [ 8340.229072][ C2] -> #1 (&p->pi_lock){-.-.}-{2:2}:
> [ 8340.229074][ C2] _raw_spin_lock_irqsave+0x3b/0x60
> [ 8340.229075][ C2] try_to_wake_up+0x88/0x1780
> [ 8340.229076][ C2] up+0x7a/0xb0
> [ 8340.229076][ C2] __up_console_sem+0x2d/0x60
> [ 8340.229077][ C2] console_unlock+0x41b/0x880
> [ 8340.229078][ C2] vprintk_emit+0x257/0x420
> [ 8340.229079][ C2] devkmsg_emit.constprop.0+0x95/0xb1
> [ 8340.229080][ C2] devkmsg_write.cold+0x48/0x74
> [ 8340.229082][ C2] do_iter_readv_writev+0x32b/0x6b0
> [ 8340.229083][ C2] do_iter_write+0x137/0x5d0
> [ 8340.229084][ C2] vfs_writev+0x147/0x4a0
> [ 8340.229084][ C2] do_writev+0x100/0x260
> [ 8340.229085][ C2] do_syscall_64+0x33/0x40
> [ 8340.229086][ C2] entry_SYSCALL_64_after_hwframe+0x44/0xae
> [ 8340.229086][ C2]
> [ 8340.229087][ C2] -> #0 ((console_sem).lock){-.-.}-{2:2}:
> [ 8340.229090][ C2] __lock_acquire+0x290e/0x58b0
> [ 8340.229090][ C2] lock_acquire+0x181/0x6a0
> [ 8340.229091][ C2] _raw_spin_lock_irqsave+0x3b/0x60
> [ 8340.229092][ C2] down_trylock+0x13/0x70
> [ 8340.229092][ C2] __down_trylock_console_sem+0x24/0x90
> [ 8340.229093][ C2] vprintk_emit+0x230/0x420
> [ 8340.229094][ C2] printk+0x96/0xb2
> [ 8340.229094][ C2] report_bug.cold+0x31/0x53
> [ 8340.229095][ C2] handle_bug+0x41/0x80
> [ 8340.229096][ C2] exc_invalid_op+0x14/0x40
> [ 8340.229096][ C2] asm_exc_invalid_op+0x12/0x20
> [ 8340.229097][ C2] ttwu_queue_wakelist+0x284/0x2f0
> [ 8340.229098][ C2] try_to_wake_up+0x5c7/0x1780
> [ 8340.229098][ C2] blk_update_request+0x711/0xe50
> [ 8340.229099][ C2] scsi_end_request+0x71/0x620
> [ 8340.229100][ C2] scsi_io_completion+0x176/0xe00
> [ 8340.229100][ C2] blk_complete_reqs+0x9a/0xd0
> [ 8340.229101][ C2] __do_softirq+0x1d0/0x881
> [ 8340.229102][ C2] __irq_exit_rcu+0x1b9/0x270
> [ 8340.229102][ C2] irq_exit_rcu+0xa/0x20
> [ 8340.229103][ C2] sysvec_call_function_single+0x6f/0x90
> [ 8340.229103][ C2] asm_sysvec_call_function_single+0x12/0x20
> [ 8340.229104][ C2] ptep_clear_flush+0x4f/0x150
> [ 8340.229105][ C2] wp_page_copy+0x839/0x1fd0
> [ 8340.229106][ C2] __handle_mm_fault+0x1f31/0x4af0
> [ 8340.229106][ C2] handle_mm_fault+0x15f/0x620
> [ 8340.229107][ C2] do_user_addr_fault+0x385/0xe30
> [ 8340.229108][ C2] exc_page_fault+0x60/0xe0
> [ 8340.229108][ C2] asm_exc_page_fault+0x1e/0x30
> [ 8340.229109][ C2]
> [ 8340.229109][ C2] other info that might help us debug this:
> [ 8340.229110][ C2]
> [ 8340.229110][ C2] Possible unsafe locking scenario:
> [ 8340.229111][ C2]
> [ 8340.229112][ C2] CPU0 CPU1
> [ 8340.229112][ C2] ---- ----
> [ 8340.229113][ C2] lock(&p->pi_lock);
> [ 8340.229114][ C2] lock((console_sem).lock);
> [ 8340.229116][ C2] lock(&p->pi_lock);
> [ 8340.229118][ C2] lock((console_sem).lock);
> [ 8340.229119][ C2]
> [ 8340.229120][ C2] *** DEADLOCK ***
> [ 8340.229120][ C2]
> [ 8340.229121][ C2] 3 locks held by systemd-udevd/558:
> [ 8340.229121][ C2] #0: ffff888118eb9d58 (&mm->mmap_lock#2){++++}-{3:3}, at: do_user_addr_fault+0x228/0xe30
> [ 8340.229125][ C2] #1: ffff88811f57f438 (ptlock_ptr(page)#2){+.+.}-{2:2}, at: wp_page_copy+0x5e5/0x1fd0
> [ 8340.229129][ C2] #2: ffff88810eee3f20 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0x88/0x1780
> [ 8340.229132][ C2]
> [ 8340.229132][ C2] stack backtrace:
> [ 8340.229133][ C2] CPU: 2 PID: 558 Comm: systemd-udevd Not tainted 5.12.0-rc2+ #1
> [ 8340.229134][ C2] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 3.2 11/22/2019
> [ 8340.229135][ C2] Call Trace:
> [ 8340.229135][ C2] <IRQ>
> [ 8340.229136][ C2] dump_stack+0x93/0xc2
> [ 8340.229136][ C2] check_noncircular+0x235/0x2b0
> [ 8340.229137][ C2] ? print_circular_bug+0x460/0x460
> [ 8340.229138][ C2] ? vsnprintf+0x830/0x15c0
> [ 8340.229138][ C2] __lock_acquire+0x290e/0x58b0
> [ 8340.229139][ C2] ? printk_sprint+0x89/0x110
> [ 8340.229139][ C2] ? lockdep_hardirqs_on_prepare+0x3e0/0x3e0
> [ 8340.229140][ C2] ? vprintk_store+0x4ba/0x630
> [ 8340.229141][ C2] lock_acquire+0x181/0x6a0
> [ 8340.229141][ C2] ? down_trylock+0x13/0x70
> [ 8340.229142][ C2] ? lock_release+0x680/0x680
> [ 8340.229142][ C2] ? printk+0x96/0xb2
> [ 8340.229143][ C2] _raw_spin_lock_irqsave+0x3b/0x60
> [ 8340.229144][ C2] ? down_trylock+0x13/0x70
> [ 8340.229144][ C2] down_trylock+0x13/0x70
> [ 8340.229145][ C2] ? printk+0x96/0xb2
> [ 8340.229145][ C2] __down_trylock_console_sem+0x24/0x90
> [ 8340.229146][ C2] vprintk_emit+0x230/0x420
> [ 8340.229147][ C2] ? ttwu_queue_wakelist+0x284/0x2f0
> [ 8340.229147][ C2] printk+0x96/0xb2
> [ 8340.229148][ C2] ? record_print_text.cold+0x11/0x11
> [ 8340.229148][ C2] ? find_held_lock+0x2c/0x110
> [ 8340.229149][ C2] report_bug.cold+0x31/0x53
> [ 8340.229150][ C2] handle_bug+0x41/0x80
> [ 8340.229150][ C2] exc_invalid_op+0x14/0x40
> [ 8340.229151][ C2] asm_exc_invalid_op+0x12/0x20
> [ 8340.229152][ C2] RIP: 0010:ttwu_queue_wakelist+0x284/0x2f0
> [ 8340.229152][ C2] Code: 34 24 e8 3f 7d 63 00 4c 8b 44 24 10 48 8b 4c 24 08 8b 34 24 e9 a1 fe ff ff e8 78 7d 63 00 e9 66 ff ff ff e8 8e 7d 63 00 eb a0 <0f> 0b 45 31 ff e9 cb fe ff ff 48 89 04 24 e8 19 7d 63 00 48 8b 04
> [ 8340.229154][ C2] RSP: 0000:ffff888811489ce0 EFLAGS: 00010046
> [ 8340.229155][ C2] RAX: 0000000000000002 RBX: ffff88810eee3240
> [ 8340.229156][ C2] Lost 55 message(s)!
>
>
> [3]
>
> [40041.712804][T135817] ------------[ cut here ]------------
> [40041.718489][T135817] WARNING: CPU: 1 PID: 135817 at kernel/sched/core.c:3175 ttwu_queue_wakelist+0x284/0x2f0
> [40041.728311][T135817] Modules linked in: null_blk dm_flakey iscsi_target_mod tcm_loop target_core_pscsi target_core_file target_core_iblock nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat ip6table_nat ip6table_mangle ip6table_raw ip6table_security iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 iptable_mangle iptable_raw bridge iptable_security stp llc ip_set rfkill nf_tables target_core_user target_core_mod nfnetlink ip6table_filter ip6_tables iptable_filter sunrpc intel_rapl_msr intel_rapl_common x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass iTCO_wdt intel_pmc_bxt iTCO_vendor_support rapl intel_cstate intel_uncore joydev lpc_ich i2c_i801 i2c_smbus ses enclosure mei_me mei ipmi_ssif ioatdma wmi acpi_ipmi ipmi_si ipmi_devintf ipmi_msghandler acpi_power_meter acpi_pad zram ip_tables ast drm_vram_helper drm_kms_helper syscopyarea sysfillrect crc32c_intel sysimgblt
> [40041.728481][T135817] fb_sys_fops cec drm_ttm_helper ttm ghash_clmulni_intel drm igb mpt3sas nvme dca i2c_algo_bit nvme_core raid_class scsi_transport_sas pkcs8_key_parser [last unloaded: null_blk]
> [40041.832215][T135817] CPU: 1 PID: 135817 Comm: fio Not tainted 5.13.0-rc5+ #1
> [40041.839262][T135817] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 3.2 11/22/2019
> [40041.847434][T135817] RIP: 0010:ttwu_queue_wakelist+0x284/0x2f0
> [40041.853266][T135817] Code: 34 24 e8 6f 71 64 00 4c 8b 44 24 10 48 8b 4c 24 08 8b 34 24 e9 a1 fe ff ff e8 a8 71 64 00 e9 66 ff ff ff e8 be 71 64 00 eb a0 <0f> 0b 45 31 ff e9 cb fe ff ff 48 89 04 24 e8 49 71 64 00 48 8b 04
> [40041.872793][T135817] RSP: 0018:ffff888106bff348 EFLAGS: 00010046
> [40041.878800][T135817] RAX: 0000000000000001 RBX: ffff888117ec3240 RCX: ffff888811440000
> [40041.886711][T135817] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffffb603d6e8
> [40041.894625][T135817] RBP: 0000000000000001 R08: ffffffffb603d6e8 R09: ffffffffb6ba6167
> [40041.902537][T135817] R10: fffffbfff6d74c2c R11: 0000000000000001 R12: 0000000000000000
> [40041.910451][T135817] R13: ffff88881145fd00 R14: 0000000000000001 R15: ffff888811440001
> [40041.918364][T135817] FS: 00007f8eabf14b80(0000) GS:ffff888811440000(0000) knlGS:0000000000000000
> [40041.927229][T135817] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [40041.933756][T135817] CR2: 000055ce81e2cc78 CR3: 000000011be92005 CR4: 00000000001706e0
> [40041.941669][T135817] Call Trace:
> [40041.944895][T135817] ? lock_is_held_type+0x98/0x110
> [40041.949860][T135817] try_to_wake_up+0x6f9/0x15e0
> [40041.954567][T135817] ? migrate_swap_stop+0x970/0x970
> [40041.959618][T135817] ? insert_work+0x193/0x2e0
> [40041.964152][T135817] __queue_work+0x4e8/0xdb0
> [40041.968599][T135817] ? try_to_grab_pending.part.0+0x439/0x530
> [40041.974429][T135817] ? hctx_unlock+0x7d/0xe0
> [40041.978790][T135817] mod_delayed_work_on+0x8c/0x100
> [40041.983755][T135817] ? cancel_delayed_work+0x1f0/0x1f0
> [40041.988982][T135817] ? __blk_mq_delay_run_hw_queue+0x95/0x4b0
> [40041.994817][T135817] kblockd_mod_delayed_work_on+0x17/0x20
> [40042.000390][T135817] blk_mq_run_hw_queue+0x125/0x270
> [40042.005439][T135817] ? blk_mq_delay_run_hw_queues+0x410/0x410
> [40042.011275][T135817] blk_mq_sched_insert_request+0x294/0x420
> [40042.017020][T135817] ? __blk_mq_sched_bio_merge+0x340/0x340
> [40042.022677][T135817] ? blk_mq_rq_ctx_init+0x99a/0xe80
> [40042.027819][T135817] blk_mq_submit_bio+0xb37/0x15f0
> [40042.032786][T135817] ? blk_mq_try_issue_list_directly+0x940/0x940
> [40042.038966][T135817] ? percpu_ref_put_many.constprop.0+0x82/0x1b0
> [40042.045148][T135817] submit_bio_noacct+0x79c/0xe60
> [40042.050023][T135817] ? blk_queue_enter+0x810/0x810
> [40042.054902][T135817] ? find_held_lock+0x2c/0x110
> [40042.059611][T135817] submit_bio+0xe4/0x4c0
> [40042.063795][T135817] ? submit_bio_noacct+0xe60/0xe60
> [40042.068847][T135817] ? bio_add_zone_append_page+0x2c0/0x2c0
> [40042.074507][T135817] ? bio_release_pages.part.0+0x10c/0x3d0
> [40042.080167][T135817] ? __blkdev_direct_IO_simple+0x436/0x7d0
> [40042.085912][T135817] __blkdev_direct_IO_simple+0x40d/0x7d0
> [40042.091488][T135817] ? bd_link_disk_holder+0x6e0/0x6e0
> [40042.096711][T135817] ? __lock_acquire+0xbbc/0x51b0
> [40042.101591][T135817] ? mark_lock+0xe4/0x18a0
> [40042.105953][T135817] ? set_init_blocksize.isra.0+0x140/0x140
> [40042.111698][T135817] ? mark_lock+0xe4/0x18a0
> [40042.116054][T135817] ? lock_is_held_type+0x98/0x110
> [40042.121021][T135817] ? find_held_lock+0x2c/0x110
> [40042.125730][T135817] blkdev_direct_IO+0xd23/0x11d0
> [40042.130607][T135817] ? __lock_acquire+0x15c2/0x51b0
> [40042.135577][T135817] ? bd_prepare_to_claim+0x2a0/0x2a0
> [40042.140799][T135817] ? __lock_acquire+0x15c2/0x51b0
> [40042.145770][T135817] generic_file_read_iter+0x1f4/0x470
> [40042.151080][T135817] blkdev_read_iter+0x100/0x190
> [40042.155871][T135817] new_sync_read+0x352/0x5d0
> [40042.160403][T135817] ? __ia32_sys_llseek+0x310/0x310
> [40042.165458][T135817] ? __cond_resched+0x15/0x30
> [40042.170076][T135817] ? inode_security+0x56/0xf0
> [40042.174698][T135817] vfs_read+0x26c/0x470
> [40042.178796][T135817] __x64_sys_pread64+0x17d/0x1d0
> [40042.183674][T135817] ? vfs_read+0x470/0x470
> [40042.187946][T135817] ? syscall_enter_from_user_mode+0x27/0x70
> [40042.193780][T135817] ? trace_hardirqs_on+0x1c/0x110
> [40042.198747][T135817] do_syscall_64+0x40/0x80
> [40042.203107][T135817] entry_SYSCALL_64_after_hwframe+0x44/0xae
> [40042.208939][T135817] RIP: 0033:0x7f8eb5cdb96f
> [40042.213297][T135817] Code: 08 89 3c 24 48 89 4c 24 18 e8 7d f3 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 48 8b 74 24 08 8b 3c 24 b8 11 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 04 24 e8 cd f3 ff ff 48 8b
> [40042.232824][T135817] RSP: 002b:00007fffaa10c9d0 EFLAGS: 00000293 ORIG_RAX: 0000000000000011
> [40042.241169][T135817] RAX: ffffffffffffffda RBX: 00000000012e2540 RCX: 00007f8eb5cdb96f
> [40042.249074][T135817] RDX: 0000000000001000 RSI: 000000000130a000 RDI: 0000000000000009
> [40042.256985][T135817] RBP: 00000000012e2540 R08: 0000000000000000 R09: 00007fffaa163080
> [40042.264898][T135817] R10: 0000000000862000 R11: 0000000000000293 R12: 00007f8e96829458
> [40042.272813][T135817] R13: 0000000000000000 R14: 0000000000001000 R15: 00000000012e2568
> [40042.280732][T135817] irq event stamp: 1042448
> [40042.285084][T135817] hardirqs last enabled at (1042447): [<ffffffffb320209e>] try_to_grab_pending.part.0+0x1ae/0x530
> [40042.295683][T135817] hardirqs last disabled at (1042448): [<ffffffffb3202b3b>] mod_delayed_work_on+0xcb/0x100
> [40042.305591][T135817] softirqs last enabled at (1041222): [<ffffffffb31b5316>] __irq_exit_rcu+0x1c6/0x270
> [40042.315150][T135817] softirqs last disabled at (1041215): [<ffffffffb31b5316>] __irq_exit_rcu+0x1c6/0x270
> [40042.324711][T135817] ---[ end trace b6f997c9a553aa02 ]---
> [40042.330118][ C1]
> [40042.330119][ C1] ======================================================
> [40042.330121][ C1] WARNING: possible circular locking dependency detected
> [40042.330123][ C1] 5.13.0-rc5+ #1 Not tainted
> [40042.330125][ C1] ------------------------------------------------------
> [40042.330126][ C1] fio/135817 is trying to acquire lock:
> [40042.330128][ C1] ffffffffb641acb8 ((console_sem).lock){-.-.}-{2:2}, at: down_trylock+0x13/0x70
> [40042.330134][ C1]
> [40042.330135][ C1] but task is already holding lock:
> [40042.330137][ C1] ffff888117ec3f30 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0x88/0x15e0
> [40042.330142][ C1]
> [40042.330144][ C1] which lock already depends on the new lock.
> [40042.330145][ C1]
> [40042.330146][ C1]
> [40042.330147][ C1] the existing dependency chain (in reverse order) is:
> [40042.330149][ C1]
> [40042.330150][ C1] -> #1 (&p->pi_lock){-.-.}-{2:2}:
> [40042.330155][ C1] _raw_spin_lock_irqsave+0x3b/0x60
> [40042.330156][ C1] try_to_wake_up+0x88/0x15e0
> [40042.330157][ C1] up+0x7a/0xb0
> [40042.330159][ C1] __up_console_sem+0x2d/0x60
> [40042.330161][ C1] console_unlock+0x3f7/0x840
> [40042.330162][ C1] vprintk_emit+0x257/0x420
> [40042.330163][ C1] devkmsg_emit.constprop.0+0x95/0xb1
> [40042.330165][ C1] devkmsg_write.cold+0x48/0x74
> [40042.330166][ C1] do_iter_readv_writev+0x32b/0x6b0
> [40042.330167][ C1] do_iter_write+0x137/0x5d0
> [40042.330169][ C1] vfs_writev+0x147/0x4a0
> [40042.330170][ C1] do_writev+0x100/0x260
> [40042.330172][ C1] do_syscall_64+0x40/0x80
> [40042.330173][ C1] entry_SYSCALL_64_after_hwframe+0x44/0xae
> [40042.330175][ C1]
> [40042.330176][ C1] -> #0 ((console_sem).lock){-.-.}-{2:2}:
> [40042.330181][ C1] __lock_acquire+0x2940/0x51b0
> [40042.330182][ C1] lock_acquire+0x181/0x6a0
> [40042.330183][ C1] _raw_spin_lock_irqsave+0x3b/0x60
> [40042.330184][ C1] down_trylock+0x13/0x70
> [40042.330185][ C1] __down_trylock_console_sem+0x24/0x90
> [40042.330186][ C1] vprintk_emit+0x230/0x420
> [40042.330187][ C1] printk+0x96/0xb2
> [40042.330187][ C1] report_bug.cold+0x31/0x53
> [40042.330188][ C1] handle_bug+0x3c/0x70
> [40042.330189][ C1] exc_invalid_op+0x14/0x40
> [40042.330189][ C1] asm_exc_invalid_op+0x12/0x20
> [40042.330190][ C1] ttwu_queue_wakelist+0x284/0x2f0
> [40042.330191][ C1] try_to_wake_up+0x6f9/0x15e0
> [40042.330192][ C1] __queue_work+0x4e8/0xdb0
> [40042.330193][ C1] mod_delayed_work_on+0x8c/0x100
> [40042.330194][ C1] kblockd_mod_delayed_work_on+0x17/0x20
> [40042.330194][ C1] blk_mq_run_hw_queue+0x125/0x270
> [40042.330195][ C1] blk_mq_sched_insert_request+0x294/0x420
> [40042.330196][ C1] blk_mq_submit_bio+0xb37/0x15f0
> [40042.330197][ C1] submit_bio_noacct+0x79c/0xe60
> [40042.330198][ C1] submit_bio+0xe4/0x4c0
> [40042.330199][ C1] __blkdev_direct_IO_simple+0x40d/0x7d0
> [40042.330199][ C1] blkdev_direct_IO+0xd23/0x11d0
> [40042.330200][ C1] generic_file_read_iter+0x1f4/0x470
> [40042.330201][ C1] blkdev_read_iter+0x100/0x190
> [40042.330202][ C1] new_sync_read+0x352/0x5d0
> [40042.330203][ C1] vfs_read+0x26c/0x470
> [40042.330203][ C1] __x64_sys_pread64+0x17d/0x1d0
> [40042.330204][ C1] do_syscall_64+0x40/0x80
> [40042.330205][ C1] entry_SYSCALL_64_after_hwframe+0x44/0xae
> [40042.330206][ C1]
> [40042.330206][ C1] other info that might help us debug this:
> [40042.330207][ C1]
> [40042.330208][ C1] Possible unsafe locking scenario:
> [40042.330208][ C1]
> [40042.330209][ C1] CPU0 CPU1
> [40042.330210][ C1] ---- ----
> [40042.330210][ C1] lock(&p->pi_lock);
> [40042.330212][ C1] lock((console_sem).lock);
> [40042.330214][ C1] lock(&p->pi_lock);
> [40042.330216][ C1] lock((console_sem).lock);
> [40042.330217][ C1]
> [40042.330218][ C1] *** DEADLOCK ***
> [40042.330218][ C1]
> [40042.330219][ C1] 3 locks held by fio/135817:
> [40042.330220][ C1] #0: ffffffffb643ae80 (rcu_read_lock){....}-{1:2}, at: __queue_work+0xa0/0xdb0
> [40042.330223][ C1] #1: ffff8888114730d8 (&pool->lock){-.-.}-{2:2}, at: __queue_work+0x2ce/0xdb0
> [40042.330227][ C1] #2: ffff888117ec3f30 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0x88/0x15e0
> [40042.330230][ C1]
> [40042.330231][ C1] stack backtrace:
> [40042.330231][ C1] CPU: 1 PID: 135817 Comm: fio Not tainted 5.13.0-rc5+ #1
> [40042.330232][ C1] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 3.2 11/22/2019
> [40042.330233][ C1] Call Trace:
> [40042.330234][ C1] dump_stack+0x93/0xc2
> [40042.330234][ C1] check_noncircular+0x235/0x2b0
> [40042.330235][ C1] ? print_circular_bug+0x1f0/0x1f0
> [40042.330236][ C1] ? enable_ptr_key_workfn+0x20/0x20
> [40042.330237][ C1] ? desc_read+0x218/0x2e0
> [40042.330237][ C1] ? vsnprintf+0x830/0x15c0
> [40042.330238][ C1] __lock_acquire+0x2940/0x51b0
> [40042.330239][ C1] ? printk_sprint+0x89/0x110
> [40042.330239][ C1] ? lockdep_hardirqs_on_prepare+0x3e0/0x3e0
> [40042.330240][ C1] ? vprintk_store+0x581/0x630
> [40042.330241][ C1] lock_acquire+0x181/0x6a0
> [40042.330242][ C1] ? down_trylock+0x13/0x70
> [40042.330242][ C1] ? lock_release+0x680/0x680
> [40042.330243][ C1] ? lock_chain_count+0x20/0x20
> [40042.330244][ C1] ? lock_downgrade+0x6a0/0x6a0
> [40042.330245][ C1] ? printk+0x96/0xb2
> [40042.330246][ C1] _raw_spin_lock_irqsave+0x3b/0x60
> [40042.330248][ C1] ? down_trylock+0x13/0x70
> [40042.330249][ C1] down_trylock+0x13/0x70
> [40042.330250][ C1] ? printk+0x96/0xb2
> [40042.330252][ C1] __down_trylock_console_sem+0x24/0x90
> [40042.330253][ C1] vprintk_emit+0x230/0x420
> [40042.330254][ C1] ? ttwu_queue_wakelist+0x284/0x2f0
> [40042.330255][ C1] printk+0x96/0xb2
> [40042.330256][ C1] ? record_print_text.cold+0x11/0x11
> [40042.330258][ C1] report_bug.cold+0x31/0x53
> [40042.330259][ C1] ? ttwu_queue_wakelist+0x284/0x2f0
> [40042.330260][ C1] handle_bug+0x3c/0x70
> [40042.330262][ C1] exc_invalid_op+0x14/0x40
> [40042.330263][ C1] asm_exc_invalid_op+0x12/0x20
> [40042.330264][ C1] RIP: 0010:ttwu_queue_wakelist+0x284/0x2f0
> [40042.330266][ C1] Code: 34 24 e8 6f 71 64 00 4c 8b 44 24 10 48 8b 4c 24 08 8b 34 24 e9 a1 fe ff ff e8 a8 71 64 00 e9 66 ff ff ff e8 be 71 64 00 eb a0 <0f> 0b 45 31 ff e9 cb
> [40042.330269][ C1] Lost 69 message(s)!
>
--
Damien Le Moal
Western Digital Research
