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INFO: rcu detected stall in ext4_file_write_iter (8)

Status: auto-obsoleted due to no activity on 2024/03/14 12:59
Subsystems: mm
[Documentation on labels]
First crash: 194d, last: 139d
▶ ▼ Similar bugs (14)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: rcu detected stall in ext4_file_write_iter 1 162d 162d 0/3 auto-obsoleted due to no activity on 2024/02/29 20:44
upstream INFO: rcu detected stall in ext4_file_write_iter (3) block 5 996d 1086d 0/26 auto-closed as invalid on 2021/11/07 19:52
upstream INFO: rcu detected stall in ext4_file_write_iter (5) mm 3 737d 737d 0/26 auto-closed as invalid on 2022/06/25 07:58
linux-6.1 INFO: rcu detected stall in ext4_file_write_iter 1 31d 31d 0/3 upstream: reported on 2024/04/01 06:27
upstream INFO: rcu detected stall in ext4_file_write_iter (7) mm bpf ext4 3 244d 287d 23/26 fixed on 2023/10/12 12:47
upstream INFO: rcu detected stall in ext4_file_write_iter (4) mm C unreliable 58 832d 861d 0/26 closed as invalid on 2022/02/08 10:32
android-49 INFO: rcu detected stall in ext4_file_write_iter syz 2 1795d 1836d 0/3 public: reported syz repro on 2019/04/23 08:58
upstream INFO: rcu detected stall in ext4_file_write_iter (2) ext4 1 1298d 1298d 0/26 auto-closed as invalid on 2021/01/10 12:58
linux-4.14 INFO: rcu detected stall in ext4_file_write_iter C 7 437d 1846d 0/1 upstream: reported C repro on 2019/04/12 16:30
upstream INFO: rcu detected stall in ext4_file_write_iter C inconclusive done 93 1360d 1892d 15/26 fixed on 2020/09/25 01:17
linux-4.19 INFO: rcu detected stall in ext4_file_write_iter C error 9 498d 1839d 0/1 upstream: reported C repro on 2019/04/20 13:09
upstream INFO: rcu detected stall in ext4_file_write_iter (6) ext4 C error 8 386d 449d 22/26 fixed on 2023/06/08 14:41
linux-4.19 BUG: soft lockup in ext4_file_write_iter 1 1042d 1042d 0/1 auto-closed as invalid on 2021/10/22 22:26
android-5-15 BUG: soft lockup in ext4_file_write_iter 4 3d19h 26d 0/2 premoderation: reported on 2024/04/06 14:01

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P47/1:b..l P17369/1:b..l
rcu: 	(detected by 1, t=10504 jiffies, g=82973, q=33 ncpus=2)
task:syz-executor.5  state:R  running task     stack:26976 pid:17369 ppid:5075   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0xee1/0x5a10 kernel/sched/core.c:6695
 preempt_schedule_irq+0x52/0x90 kernel/sched/core.c:7007
 irqentry_exit+0x35/0x80 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:folio_memcg_lock+0x133/0x630 mm/memcontrol.c:2133
Code: b8 01 00 00 00 31 c9 31 d2 31 f6 4c 89 ef e8 84 02 84 ff 4c 89 fe 4c 89 ef e8 a9 f3 83 ff 9c 58 f6 c4 02 5a 0f 85 57 03 00 00 <4c> 8d ad 40 09 00 00 be 04 00 00 00 4c 89 ef e8 29 31 f8 ff 4c 89
RSP: 0018:ffffc90005567948 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffffea000136e6c0 RCX: ffffffff81e39304
RDX: 0000000000000000 RSI: ffffffff8a8c9ca0 RDI: ffffffff8ae90c20
RBP: ffff888076ca2000 R08: 0000000000000001 R09: fffffbfff23385d5
R10: ffffffff919c2eaf R11: 0000000000000000 R12: dffffc0000000000
R13: ffff888076ca27f0 R14: ffffea000136e6f8 R15: ffffffff81e38f2c
 mark_buffer_dirty+0x2b1/0x3e0 fs/buffer.c:1208
 __block_commit_write+0x108/0x270 fs/buffer.c:2192
 block_write_end+0xc8/0x250 fs/buffer.c:2268
 ext4_da_do_write_end fs/ext4/inode.c:2951 [inline]
 ext4_da_write_end+0x1e1/0x1170 fs/ext4/inode.c:3023
 generic_perform_write+0x32f/0x600 mm/filemap.c:3980
 ext4_buffered_write_iter+0x11f/0x3c0 fs/ext4/file.c:299
 ext4_file_write_iter+0x7f7/0x1860 fs/ext4/file.c:717
 call_write_iter include/linux/fs.h:1956 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x650/0xe40 fs/read_write.c:584
 ksys_write+0x12f/0x250 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f204867cae9
RSP: 002b:00007f20493540c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f204879c050 RCX: 00007f204867cae9
RDX: 00000000000ffe00 RSI: 0000000020004200 RDI: 0000000000000005
RBP: 00007f20486c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f204879c050 R15: 00007ffdcd2efed8
 </TASK>
task:kworker/u4:3    state:R  running task     stack:22896 pid:47    ppid:2      flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0xee1/0x5a10 kernel/sched/core.c:6695
 preempt_schedule_irq+0x52/0x90 kernel/sched/core.c:7007
 irqentry_exit+0x35/0x80 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:lock_acquire+0x1ef/0x510 kernel/locking/lockdep.c:5721
Code: c1 05 a5 f5 9a 7e 83 f8 01 0f 85 b0 02 00 00 9c 58 f6 c4 02 0f 85 9b 02 00 00 48 85 ed 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24
RSP: 0018:ffffc90000d8fac8 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 1ffff920001b1f5b RCX: 0000000000000001
RDX: 1ffff11002c5cd68 RSI: ffffffff8a8c9fa0 RDI: ffffffff8ae90c20
RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff23385d0
R10: ffffffff919c2e87 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffffffff8cba7960 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:303 [inline]
 rcu_read_lock include/linux/rcupdate.h:749 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
 batadv_nc_worker+0x16e/0x10e0 net/batman-adv/network-coding.c:719
 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630
 process_scheduled_works kernel/workqueue.c:2703 [inline]
 worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784
 kthread+0x33c/0x440 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
 </TASK>
rcu: rcu_preempt kthread starved for 10450 jiffies! g82973 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:26832 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0xee1/0x5a10 kernel/sched/core.c:6695
 schedule+0xe7/0x1b0 kernel/sched/core.c:6771
 schedule_timeout+0x157/0x2c0 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x1ec/0xa50 kernel/rcu/tree.c:1613
 rcu_gp_kthread+0x249/0x380 kernel/rcu/tree.c:1812
 kthread+0x33c/0x440 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 17392 Comm: syz-executor.0 Not tainted 6.6.0-rc6-syzkaller-00244-gc3200081020d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
RIP: 0010:csd_lock_wait kernel/smp.c:300 [inline]
RIP: 0010:smp_call_function_many_cond+0x4d6/0x1570 kernel/smp.c:844
Code: 0b 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 fc 4c 89 fd 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 ac 8a 0b 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 3c 0e 00 00 8b 43 08 31
RSP: 0000:ffffc90004bafa08 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b98414c0 RCX: 0000000000000000
RDX: ffff8880826ce080 RSI: ffffffff817b3d84 RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: dffffc0000000000 R12: ffffed1017308299
R13: 0000000000000001 R14: ffff8880b993d900 R15: ffff8880b98414c8
FS:  0000555556d76480(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbcb699c01c CR3: 0000000028db6000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1012
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:87 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:944 [inline]
 flush_tlb_mm_range+0x38a/0x580 arch/x86/mm/tlb.c:1030
 flush_tlb_page arch/x86/include/asm/tlbflush.h:254 [inline]
 ptep_clear_flush+0x132/0x170 mm/pgtable-generic.c:101
 wp_page_copy mm/memory.c:3142 [inline]
 do_wp_page+0x16fe/0x3420 mm/memory.c:3449
 handle_pte_fault mm/memory.c:4994 [inline]
 __handle_mm_fault+0x1d1b/0x3e10 mm/memory.c:5119
 handle_mm_fault+0x478/0xa00 mm/memory.c:5284
 do_user_addr_fault+0x30b/0x1000 arch/x86/mm/fault.c:1364
 handle_page_fault arch/x86/mm/fault.c:1505 [inline]
 exc_page_fault+0x5c/0xd0 arch/x86/mm/fault.c:1561
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
RIP: 0033:0x7fbcb6836c3c
Code: 7e 16 09 00 31 c0 e8 93 03 ff ff 48 8d 1d 5c 53 16 00 83 3d 5d 6d 16 00 00 48 8d ab 00 1a 00 00 7f 25 e9 88 fd ff ff 48 8b 00 <89> 83 9c 00 00 00 31 f6 e8 b7 ea ff ff 48 81 c3 d0 00 00 00 48 39
RSP: 002b:00007ffed7101bd0 EFLAGS: 00010202
RAX: 000000000003ffff RBX: 00007fbcb699bf80 RCX: 00000000001b11b0
RDX: 00000000000003e0 RSI: 00007ffed7101bb0 RDI: 00007fbcb699bf80
RBP: 00007fbcb699d980 R08: 00000000000006ee R09: 0000000000000001
R10: 00007ffed71d8080 R11: 00000000027d0bee R12: 00000000001b158f
R13: ffffffffffffffff R14: 00007fbcb6400000 R15: 00000000001b124e
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/10/21 05:35 upstream c3200081020d 361b23dc .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_write_iter
2023/12/15 12:49 net-next 1b666016d0ad 3222d10c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: rcu detected stall in ext4_file_write_iter
2023/11/26 09:48 net-next 9f1f6111fd5d 5b429f39 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: rcu detected stall in ext4_file_write_iter
* Struck through repros no longer work on HEAD.