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INFO: rcu detected stall in generic_file_write_iter (2)

Status: upstream: reported on 2024/12/19 01:50
Reported-by: syzbot+8fe6306e202244fa432b@syzkaller.appspotmail.com
First crash: 356d, last: 4d18h
▶ ▼ Similar bugs (13)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in generic_file_write_iter (3) mm 1 1 2198d 2198d 0/29 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in generic_file_write_iter (2) exfat 1 2 2413d 2452d 0/29 auto-closed as invalid on 2019/10/25 09:01
upstream BUG: soft lockup in generic_file_write_iter (2) mm 1 8 884d 872d 0/29 auto-obsoleted due to no activity on 2023/10/18 13:34
linux-5.15 INFO: rcu detected stall in generic_file_write_iter (2) 1 32 7d10h 642d 0/3 upstream: reported on 2024/03/08 18:29
linux-5.15 INFO: rcu detected stall in generic_file_write_iter 1 1 828d 828d 0/3 auto-obsoleted due to no activity on 2023/12/13 17:16
upstream INFO: rcu detected stall in generic_file_write_iter (4) cgroups 1 1 2131d 2127d 0/29 auto-closed as invalid on 2020/05/09 11:43
upstream BUG: soft lockup in generic_file_write_iter net mm fs 1 2 1070d 1104d 0/29 auto-obsoleted due to no activity on 2023/04/05 19:12
upstream INFO: rcu detected stall in generic_file_write_iter mm 1 58 2477d 2619d 0/29 closed as dup on 2018/10/27 15:28
upstream INFO: rcu detected stall in generic_file_write_iter (5) fs 1 2 1965d 1973d 0/29 auto-closed as invalid on 2020/10/22 01:02
upstream INFO: rcu detected stall in generic_file_write_iter (7) block 1 1 150d 150d 0/29 auto-obsoleted due to no activity on 2025/10/11 00:51
upstream INFO: rcu detected stall in generic_file_write_iter (6) cgroups mm 1 2 1451d 1508d 0/29 closed as invalid on 2022/02/08 09:50
linux-6.1 INFO: rcu detected stall in generic_file_write_iter 1 18 485d 598d 0/3 auto-obsoleted due to no activity on 2024/11/12 08:46
android-5-15 BUG: soft lockup in generic_file_write_iter 1 1 577d 577d 0/2 auto-obsoleted due to no activity on 2024/08/10 08:10

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4857/1:b..l
	(detected by 0, t=10503 jiffies, g=13973, q=9 ncpus=2)
task:syz.2.93        state:R  running task     stack:25760 pid:4857  ppid:4272   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:check_region_inline mm/kasan/generic.c:169 [inline]
RIP: 0010:kasan_check_range+0xf/0x290 mm/kasan/generic.c:189
Code: 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 00 00 cc cc 00 00 cc cc 00 00 cc cc b0 01 48 85 f6 0f 84 a4 01 00 00 41 57 41 56 <53> 49 89 f8 49 01 f0 0f 82 57 02 00 00 49 89 f8 49 c1 e8 2f 41 81
RSP: 0018:ffffc9000c28f340 EFLAGS: 00000202
RAX: ffffffff81db2901 RBX: 0000000000000000 RCX: ffffffff81db29d6
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88801ad1f590
RBP: dffffc0000000000 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c449 R11: 1ffffffff215c448 R12: ffff88801ad1f590
R13: 1ffffffff1986ca8 R14: ffff88801ad1f550 R15: 0000000000000000
 instrument_atomic_read include/linux/instrumented.h:72 [inline]
 atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
 __page_table_check_zero+0x1b6/0x4b0 mm/page_table_check.c:154
 prep_new_page mm/page_alloc.c:2539 [inline]
 get_page_from_freelist+0x1a26/0x1ac0 mm/page_alloc.c:4328
 __alloc_pages+0x1df/0x4e0 mm/page_alloc.c:5614
 __folio_alloc+0xe/0x30 mm/page_alloc.c:5646
 vma_alloc_folio+0x4a3/0x900 mm/mempolicy.c:2243
 shmem_alloc_folio mm/shmem.c:1589 [inline]
 shmem_alloc_and_acct_folio+0x42e/0xb60 mm/shmem.c:1613
 shmem_get_folio_gfp+0x1361/0x3400 mm/shmem.c:1941
 shmem_get_folio mm/shmem.c:2072 [inline]
 shmem_write_begin+0xee/0x3f0 mm/shmem.c:2556
 generic_perform_write+0x2db/0x560 mm/filemap.c:3846
 __generic_file_write_iter+0x172/0x430 mm/filemap.c:3974
 generic_file_write_iter+0xab/0x2e0 mm/filemap.c:4006
 call_write_iter include/linux/fs.h:2265 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x44c/0x960 fs/read_write.c:584
 ksys_write+0x143/0x240 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe6fc98e1ff
RSP: 002b:00007fe6fd7cadf0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007fe6fc98e1ff
RDX: 0000000001000000 RSI: 00007fe6f27f7000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000000050e6
R10: 0000000000000002 R11: 0000000000000293 R12: 0000000000000003
R13: 00007fe6fd7caef0 R14: 00007fe6fd7caeb0 R15: 00007fe6f27f7000
 </TASK>
rcu: rcu_preempt kthread starved for 10518 jiffies! g13973 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:27840 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4418 Comm: udevd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:29 [inline]
RIP: 0010:rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline]
RIP: 0010:rcu_is_watching+0x56/0xa0 kernel/rcu/tree.c:721
Code: f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 a0 f0 65 00 48 c7 c3 c8 57 03 00 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 <84> c0 75 2f 8b 03 65 ff 0d 65 5a 97 7e 74 0c 83 e0 04 c1 e8 02 5b
RSP: 0018:ffffc900047ef6a0 EFLAGS: 00000a06
RAX: 0000000000000000 RBX: ffff8880b8f357c8 RCX: 2bc34c199890d300
RDX: 0000000000000000 RSI: ffffffff8adef740 RDI: ffffffff8adef700
RBP: ffffc900047ef7d0 R08: dffffc0000000000 R09: fffffbfff1c3ed56
R10: fffffbfff1c3ed56 R11: 1ffffffff1c3ed55 R12: 0000555b819dd000
R13: dffffc0000000000 R14: ffffffff8c5e4988 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555b819cea38 CR3: 0000000028957000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 trace_lock_release include/trace/events/lock.h:69 [inline]
 lock_release+0xd4/0x910 kernel/locking/lockdep.c:5673
 ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline]
 zap_pte_range mm/memory.c:1435 [inline]
 zap_pmd_range mm/memory.c:1574 [inline]
 zap_pud_range mm/memory.c:1603 [inline]
 zap_p4d_range mm/memory.c:1624 [inline]
 unmap_page_range+0x1924/0x2500 mm/memory.c:1645
 unmap_vmas+0x22c/0x330 mm/memory.c:1730
 exit_mmap+0x1cc/0x8e0 mm/mmap.c:3250
 __mmput+0x118/0x3c0 kernel/fork.c:1200
 exit_mm+0x1e6/0x2c0 kernel/exit.c:565
 do_exit+0x8c1/0x2400 kernel/exit.c:867
 do_group_exit+0x217/0x2d0 kernel/exit.c:1022
 __do_sys_exit_group kernel/exit.c:1033 [inline]
 __se_sys_exit_group kernel/exit.c:1031 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1031
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f3d286f16c5
Code: Unable to access opcode bytes at 0x7f3d286f169b.
RSP: 002b:00007ffc55c299e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000555b819e9f80 RCX: 00007f3d286f16c5
RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000
RBP: 0000555b819c5910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc55c29a30 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
sched: RT throttling activated
vkms_vblank_simulate: vblank timer overrun

Crashes (12):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/06 05:47 linux-6.1.y f6e38ae624cf d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in generic_file_write_iter
2025/12/05 10:54 linux-6.1.y f6e38ae624cf d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in generic_file_write_iter
2025/12/04 02:50 linux-6.1.y f6e38ae624cf d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in generic_file_write_iter
2025/11/02 17:38 linux-6.1.y f6e38ae624cf 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in generic_file_write_iter
2025/08/31 16:47 linux-6.1.y f89b6e15694c 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in generic_file_write_iter
2025/08/07 23:39 linux-6.1.y 3594f306da12 04cffc22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in generic_file_write_iter
2025/06/14 01:08 linux-6.1.y 58485ff1a74f 0e8da31f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in generic_file_write_iter
2025/04/17 21:02 linux-6.1.y 420102835862 229db4cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in generic_file_write_iter
2025/04/02 11:35 linux-6.1.y 8e60a714ba3b c799dfdd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in generic_file_write_iter
2025/03/23 05:33 linux-6.1.y 344a09659766 4e8d3850 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in generic_file_write_iter
2025/01/28 00:13 linux-6.1.y 75cefdf153f5 18070896 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in generic_file_write_iter
2024/12/19 01:49 linux-6.1.y 52f863f820fd 1432fc84 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in generic_file_write_iter
* Struck through repros no longer work on HEAD.