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INFO: rcu detected stall in generic_file_write_iter (2)

Status: upstream: reported on 2024/03/08 18:29
Reported-by: syzbot+bb21d42787b313521a4c@syzkaller.appspotmail.com
First crash: 828d, last: 6d18h
▶ ▼ 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 2385d 2385d 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 2600d 2639d 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 1071d 1059d 0/29 auto-obsoleted due to no activity on 2023/10/18 13:34
linux-6.1 INFO: rcu detected stall in generic_file_write_iter (2) 1 17 115d 543d 0/3 auto-obsoleted due to no activity on 2026/05/31 05:00
linux-5.15 INFO: rcu detected stall in generic_file_write_iter 1 1 1015d 1015d 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 2318d 2314d 0/29 auto-closed as invalid on 2020/05/09 11:43
upstream BUG: soft lockup in generic_file_write_iter net fs mm 1 2 1256d 1291d 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 2663d 2806d 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 2152d 2159d 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 337d 337d 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) mm cgroups 1 2 1638d 1694d 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 672d 785d 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 764d 764d 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: 	0-....: (0 ticks this GP) idle=c1d/1/0x4000000000000002 softirq=52955/52955 fqs=5201 
	(detected by 1, t=10502 jiffies, g=70253, q=1454)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 18803 Comm: syz.7.3862 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
Code: 89 c4 48 89 e7 e8 da 4d dd ff e9 85 03 00 00 90 90 90 90 90 0f 01 ca fc 6a ff e8 85 02 00 00 48 89 c4 48 89 e7 e8 aa 52 dd ff <e9> 65 03 00 00 90 90 90 90 90 0f 01 ca fc 6a ff e8 65 02 00 00 48
RSP: 0018:ffffc90000007a58 EFLAGS: 00000082
RAX: 6acb2ffe2f369500 RBX: 0000000000000000 RCX: 6acb2ffe2f369500
RDX: dffffc0000000000 RSI: ffffffff8a2b3180 RDI: ffffffff8a7a09c0
RBP: 0000000000000000 R08: ffffffff901d815f R09: 1ffffffff203b02b
R10: dffffc0000000000 R11: fffffbfff203b02c R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f3af07936c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000022000 CR3: 000000002a287000 CR4: 00000000003506f0
DR0: 0000000000000004 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
RIP: 0010:rcu_read_unlock_special+0x7f/0x4a0 kernel/rcu/tree_plugin.h:674
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 f2 cc 9c 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc90000007b00 EFLAGS: 00000206
RAX: 6acb2ffe2f369500 RBX: 1ffff92000000f64 RCX: 6acb2ffe2f369500
RDX: dffffc0000000000 RSI: ffffffff8a2b3180 RDI: ffffffff8a7a09c0
RBP: ffffc90000007be0 R08: ffffffff901d815f R09: 1ffffffff203b02b
R10: dffffc0000000000 R11: fffffbfff203b02c R12: ffffffff8c323800
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 ieee80211_rx_napi+0x20f/0x390 net/mac80211/rx.c:5019
 ieee80211_rx include/net/mac80211.h:4573 [inline]
 ieee80211_handle_queued_frames+0x105/0x1b0 net/mac80211/main.c:237
 tasklet_action_common+0x2ad/0x410 kernel/softirq.c:806
 handle_softirqs+0x339/0x830 kernel/softirq.c:576
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:preempt_schedule_irq+0xb6/0x160 kernel/sched/core.c:6799
Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 7f bf 01 00 00 00 e8 a5 c1 8c f7 e8 e0 b1 b9 f7 fb bf 01 00 00 00 <e8> 65 b5 ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f
RSP: 0018:ffffc9000338f120 EFLAGS: 00000282
RAX: 6acb2ffe2f369500 RBX: 0000000000000000 RCX: 6acb2ffe2f369500
RDX: dffffc0000000000 RSI: ffffffff8a2b3180 RDI: 0000000000000001
RBP: ffffc9000338f1d0 R08: ffffffff901d815f R09: 1ffffffff203b02b
R10: dffffc0000000000 R11: fffffbfff203b02c R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92000671e24
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:84 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x92/0x290 mm/kasan/generic.c:189
Code: 49 83 ff 10 7f 29 4d 85 ff 0f 84 38 01 00 00 4c 89 cb 48 f7 d3 4c 01 f3 41 80 3b 00 0f 85 86 01 00 00 49 ff c3 48 ff c3 75 ee <e9> 18 01 00 00 44 89 dd 83 e5 07 0f 84 b5 00 00 00 41 80 3b 00 4d
RSP: 0018:ffffc9000338f290 EFLAGS: 00000256
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff815d25d6
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8d8a06e8
RBP: ffffc9000338f3e0 R08: ffffffff8d8a06ef R09: 1ffffffff1b140dd
R10: dffffc0000000000 R11: fffffbfff1b140de R12: dffffc0000000001
R13: 1ffff92000671e64 R14: 1ffffffff1b140dd R15: 0000000000000001
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 cpumask_test_cpu include/linux/cpumask.h:344 [inline]
 cpu_online include/linux/cpumask.h:895 [inline]
 trace_lock_acquire include/trace/events/lock.h:13 [inline]
 lock_acquire+0xb6/0x400 kernel/locking/lockdep.c:5594
 __fs_reclaim_acquire mm/page_alloc.c:4580 [inline]
 fs_reclaim_acquire+0x6d/0x100 mm/page_alloc.c:4594
 prepare_alloc_pages+0x15a/0x5f0 mm/page_alloc.c:5272
 __alloc_pages+0x11b/0x480 mm/page_alloc.c:5490
 alloc_pages_vma+0x393/0x7c0 mm/mempolicy.c:2146
 shmem_alloc_page mm/shmem.c:1586 [inline]
 shmem_alloc_and_acct_page+0x47f/0xbe0 mm/shmem.c:1611
 shmem_getpage_gfp+0x14f4/0x2d40 mm/shmem.c:1906
 shmem_getpage mm/shmem.c:151 [inline]
 shmem_write_begin+0xcd/0x1a0 mm/shmem.c:2474
 generic_perform_write+0x2b6/0x550 mm/filemap.c:3785
 __generic_file_write_iter+0x25f/0x4e0 mm/filemap.c:3912
 generic_file_write_iter+0xa6/0x1b0 mm/filemap.c:3944
 call_write_iter include/linux/fs.h:2173 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x745/0xd60 fs/read_write.c:594
 ksys_write+0x152/0x260 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f3af2539e59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3af0793028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f3af27b2fa0 RCX: 00007f3af2539e59
RDX: 00000000002a979d RSI: 0000200000000000 RDI: 0000000000000007
RBP: 00007f3af25cfd6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3af27b3038 R14: 00007f3af27b2fa0 R15: 00007fffa4f014f8
 </TASK>

Crashes (39):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/06/08 23:14 linux-5.15.y dc027a595035 656e94c6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in generic_file_write_iter
2026/03/30 06:09 linux-5.15.y 91d48252ad4b b5ceaad2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2026/02/10 10:28 linux-5.15.y 7b232985052f 4ab09a02 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2026/02/09 17:09 linux-5.15.y 7b232985052f df949cd9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2026/01/13 04:23 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/12/23 21:41 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/12/20 01:01 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/12/03 13:08 linux-5.15.y cc5ec8769306 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/11/10 14:27 linux-5.15.y cc5ec8769306 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/11/03 17:59 linux-5.15.y cc5ec8769306 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/11/02 05:02 linux-5.15.y cc5ec8769306 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/08/17 10:48 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in generic_file_write_iter
2025/08/14 23:36 linux-5.15.y c79648372d02 5d8c2ac2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/08/12 10:31 linux-5.15.y c79648372d02 c06e8995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in generic_file_write_iter
2025/07/17 15:48 linux-5.15.y 89950c454265 0d1223f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/04/21 19:41 linux-5.15.y f7347f400572 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/03/19 01:25 linux-5.15.y 0c935c049b5c 22a6c2b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/02/07 09:54 linux-5.15.y c16c81c81336 53657d1b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/01/05 20:37 linux-5.15.y 91786f140358 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/11/25 11:35 linux-5.15.y 0a51d2d4527b 68da6d95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/10/04 02:05 linux-5.15.y 3a5928702e71 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/10/01 02:03 linux-5.15.y 3a5928702e71 bbd4e0a4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/09/25 05:30 linux-5.15.y 3a5928702e71 5643e0e9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/09/25 05:25 linux-5.15.y 3a5928702e71 5643e0e9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/08/25 12:46 linux-5.15.y fa93fa65db6e d7d32352 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/08/23 15:54 linux-5.15.y fa93fa65db6e d7d32352 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/08/14 05:45 linux-5.15.y 7e89efd3ae1c bde81f6f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/08/11 14:11 linux-5.15.y 7e89efd3ae1c 6f4edef4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/08/06 05:48 linux-5.15.y 7e89efd3ae1c e1bdb00a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/07/02 15:21 linux-5.15.y 4878aadf2d15 07f0a0a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/06/26 23:11 linux-5.15.y 4878aadf2d15 c6d33a01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/06/20 01:11 linux-5.15.y 4878aadf2d15 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/06/19 05:21 linux-5.15.y 4878aadf2d15 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/06/19 01:58 linux-5.15.y 4878aadf2d15 639d6cdf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/05/24 04:21 linux-5.15.y 83655231580b 8f98448e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/04/30 16:34 linux-5.15.y b925f60c6ee7 3ce4924c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/04/26 10:25 linux-5.15.y c52b9710c83d 8bdc0f22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/03/08 18:28 linux-5.15.y 574362648507 8e75c913 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/08/29 09:14 linux-5.15.y fa93fa65db6e ef3de9e8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: rcu detected stall in generic_file_write_iter
* Struck through repros no longer work on HEAD.