INFO: rcu detected stall in sendfile64

Status: auto-obsoleted due to no activity on 2026/02/15 23:07
Reported-by: syzbot+38f133e45651dc8c717c@syzkaller.appspotmail.com
First crash: 335d, last: 335d
▶ ▼ Similar bugs (17)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 INFO: rcu detected stall in sendfile64 origin:upstream 1 syz, C inconclusive 2 68d 121d 0/2 upstream: reported C repro on 2026/06/10 03:23
linux-5.15 INFO: rcu detected stall in sendfile64 (2) origin:upstream 1 syz, C inconclusive 28 5d19h 96d 0/3 upstream: reported C repro on 2026/07/04 16:00
linux-4.14 INFO: rcu detected stall in sendfile64 1 1 2737d 2737d 0/1 auto-closed as invalid on 2019/10/08 13:45
linux-4.14 INFO: rcu detected stall in sendfile64 (2) 1 3 2255d 2410d 0/1 auto-closed as invalid on 2020/12/03 20:18
upstream INFO: rcu detected stall in sendfile64 prio:high mm 1 42 30d 236d 0/29 upstream: reported on 2026/02/14 22:22
upstream INFO: rcu detected stall in sys_sendfile64 (3) mm 1 2 1627d 1627d 0/29 auto-closed as invalid on 2022/06/25 08:10
upstream INFO: rcu detected stall in sys_sendfile64 (4) net 1 1 1368d 1368d 0/29 auto-obsoleted due to no activity on 2023/04/18 07:19
upstream INFO: rcu detected stall in sys_sendfile64 (6) fs mm 1 6 713d 874d 0/29 auto-obsoleted due to no activity on 2025/01/24 02:27
linux-5.15 INFO: rcu detected stall in sys_sendfile64 (2) 1 1 688d 688d 0/3 auto-obsoleted due to no activity on 2025/02/27 23:01
upstream INFO: rcu detected stall in sys_sendfile64 lsm 1 syz, C 4 2851d 2851d 0/29 closed as invalid on 2018/12/19 10:12
upstream INFO: rcu detected stall in sys_sendfile64 (2) 1 syz, C done error 100 1737d 2820d 0/29 closed as invalid on 2022/02/08 10:47
linux-4.19 INFO: rcu detected stall in sys_sendfile64 (2) 1 3 2396d 2447d 0/1 auto-closed as invalid on 2020/07/16 06:45
upstream INFO: rcu detected stall in sys_sendfile64 (7) mm 1 1 609d 609d 0/29 auto-obsoleted due to no activity on 2025/05/07 22:38
linux-6.1 INFO: rcu detected stall in sys_sendfile64 1 1 1241d 1241d 0/3 auto-obsoleted due to no activity on 2023/08/24 12:36
upstream INFO: rcu detected stall in sys_sendfile64 (5) fs 1 1 1059d 1059d 0/29 auto-obsoleted due to no activity on 2024/01/14 10:13
linux-4.19 INFO: rcu detected stall in sys_sendfile64 1 1 2730d 2730d 0/1 auto-closed as invalid on 2019/10/16 04:09
linux-5.15 INFO: rcu detected stall in sys_sendfile64 1 1 805d 805d 0/3 auto-obsoleted due to no activity on 2024/11/03 00:47

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 ticks this GP) idle=5ef/1/0x4000000000000000 softirq=55104/55104 fqs=0 
	(detected by 1, t=10502 jiffies, g=94405, q=270)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 16704 Comm: syz.6.2968 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:lock_acquire+0x1fb/0x3f0 kernel/locking/lockdep.c:5627
Code: f6 84 24 81 00 00 00 02 0f 85 f6 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 4b c7 44 3d 00 00 00 00 00 <66> 43 c7 44 3d 09 00 00 43 c6 44 3d 0b 00 65 48 8b 04 25 28 00 00
RSP: 0018:ffffc90000007b40 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: a47ebbe991eea900
RDX: 0000000000000000 RSI: ffffffff8a0b2f00 RDI: ffffffff8a59e580
RBP: ffffc90000007c60 R08: dffffc0000000000 R09: fffffbfff1ff7c19
R10: fffffbfff1ff7c19 R11: 1ffffffff1ff7c18 R12: ffffffff8c11c760
R13: 1ffff92000000f74 R14: 0000000000000046 R15: dffffc0000000000
FS:  00007ff7a660e6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000630dc000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313
 rcu_read_lock include/linux/rcupdate.h:740 [inline]
 advance_sched+0x6ca/0x940 net/sched/sch_taprio.c:769
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x53d/0xc40 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/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: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+0x71/0x290 mm/kasan/generic.c:189
Code: 00 fc ff df 4f 8d 0c 03 48 8d 5c 37 ff 48 c1 eb 03 4e 8d 14 3b 4d 89 d6 4d 29 ce 49 83 fe 10 7f 26 4d 85 f6 0f 84 39 01 00 00 <48> f7 d3 4c 01 db 41 80 39 00 0f 85 c1 01 00 00 49 ff c1 48 ff c3
RSP: 0018:ffffc90002e8ecc8 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 1ffff920005d1dc4 RCX: ffffffff813482dd
RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc90002e8ee18
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff520005d1dc3
R10: fffff520005d1dc5 R11: 1ffff920005d1dc3 R12: 1ffffffff1be67e6
R13: dffffc0000000000 R14: 0000000000000002 R15: dffffc0000000001
 memset+0x1e/0x40 mm/kasan/shadow.c:44
 unwind_next_frame+0xa3d/0x1d90 arch/x86/kernel/unwind_orc.c:547
 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
 save_stack+0xf3/0x1e0 mm/page_owner.c:119
 __set_page_owner+0x41/0x2d0 mm/page_owner.c:181
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192
 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5487
 push_pipe+0x367/0x630 lib/iov_iter.c:578
 __pipe_get_pages lib/iov_iter.c:1380 [inline]
 pipe_get_pages+0x2fb/0x5e0 lib/iov_iter.c:1410
 dio_refill_pages fs/direct-io.c:173 [inline]
 dio_get_page fs/direct-io.c:217 [inline]
 do_direct_IO fs/direct-io.c:938 [inline]
 do_blockdev_direct_IO fs/direct-io.c:1276 [inline]
 __blockdev_direct_IO+0x1060/0x3c90 fs/direct-io.c:1368
 blockdev_direct_IO include/linux/fs.h:3345 [inline]
 reiserfs_direct_IO+0xeb/0x200 fs/reiserfs/inode.c:3263
 generic_file_read_iter+0x2be/0x490 mm/filemap.c:2772
 call_read_iter include/linux/fs.h:2167 [inline]
 generic_file_splice_read+0x3a2/0x590 fs/splice.c:311
 do_splice_to fs/splice.c:807 [inline]
 splice_direct_to_actor+0x417/0xbd0 fs/splice.c:881
 do_splice_direct+0x1b6/0x2c0 fs/splice.c:1008
 do_sendfile+0x5d5/0xec0 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1317 [inline]
 __se_sys_sendfile64+0x13b/0x190 fs/read_write.c:1303
 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: 0033:0x7ff7a83c86c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff7a660e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007ff7a861f090 RCX: 00007ff7a83c86c9
RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000006
RBP: 00007ff7a844af91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000800000009 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff7a861f128 R14: 00007ff7a861f090 R15: 00007ffdef53f598
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g94405 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=42942
rcu: rcu_preempt kthread starved for 10502 jiffies! g94405 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
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:I stack:27008 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 16704 Comm: syz.6.2968 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:132 [inline]
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x82/0x100 kernel/locking/spinlock.c:194
Code: 00 fc ff df 4b 89 04 27 48 83 c7 18 48 8b 75 08 e8 83 9f a9 f7 4c 89 f7 e8 4b 74 aa f7 f7 c3 00 02 00 00 74 05 e8 de 0d cb f7 <48> c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7
RSP: 0018:ffffc90000007c80 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000806 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880b902a240
RBP: ffffc90000007d10 R08: dffffc0000000000 R09: ffffed1017205449
R10: ffffed1017205449 R11: 1ffff11017205448 R12: dffffc0000000000
R13: 1ffff1101720546a R14: ffff8880b902a240 R15: 1ffff92000000f90
FS:  00007ff7a660e6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000630dc000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __run_hrtimer kernel/time/hrtimer.c:1681 [inline]
 __hrtimer_run_queues+0x441/0xc40 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/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: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+0x71/0x290 mm/kasan/generic.c:189
Code: 00 fc ff df 4f 8d 0c 03 48 8d 5c 37 ff 48 c1 eb 03 4e 8d 14 3b 4d 89 d6 4d 29 ce 49 83 fe 10 7f 26 4d 85 f6 0f 84 39 01 00 00 <48> f7 d3 4c 01 db 41 80 39 00 0f 85 c1 01 00 00 49 ff c1 48 ff c3
RSP: 0018:ffffc90002e8ecc8 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 1ffff920005d1dc4 RCX: ffffffff813482dd
RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc90002e8ee18
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff520005d1dc3
R10: fffff520005d1dc5 R11: 1ffff920005d1dc3 R12: 1ffffffff1be67e6
R13: dffffc0000000000 R14: 0000000000000002 R15: dffffc0000000001
 memset+0x1e/0x40 mm/kasan/shadow.c:44
 unwind_next_frame+0xa3d/0x1d90 arch/x86/kernel/unwind_orc.c:547
 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
 save_stack+0xf3/0x1e0 mm/page_owner.c:119
 __set_page_owner+0x41/0x2d0 mm/page_owner.c:181
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192
 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5487
 push_pipe+0x367/0x630 lib/iov_iter.c:578
 __pipe_get_pages lib/iov_iter.c:1380 [inline]
 pipe_get_pages+0x2fb/0x5e0 lib/iov_iter.c:1410
 dio_refill_pages fs/direct-io.c:173 [inline]
 dio_get_page fs/direct-io.c:217 [inline]
 do_direct_IO fs/direct-io.c:938 [inline]
 do_blockdev_direct_IO fs/direct-io.c:1276 [inline]
 __blockdev_direct_IO+0x1060/0x3c90 fs/direct-io.c:1368
 blockdev_direct_IO include/linux/fs.h:3345 [inline]
 reiserfs_direct_IO+0xeb/0x200 fs/reiserfs/inode.c:3263
 generic_file_read_iter+0x2be/0x490 mm/filemap.c:2772
 call_read_iter include/linux/fs.h:2167 [inline]
 generic_file_splice_read+0x3a2/0x590 fs/splice.c:311
 do_splice_to fs/splice.c:807 [inline]
 splice_direct_to_actor+0x417/0xbd0 fs/splice.c:881
 do_splice_direct+0x1b6/0x2c0 fs/splice.c:1008
 do_sendfile+0x5d5/0xec0 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1317 [inline]
 __se_sys_sendfile64+0x13b/0x190 fs/read_write.c:1303
 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: 0033:0x7ff7a83c86c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff7a660e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007ff7a861f090 RCX: 00007ff7a83c86c9
RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000006
RBP: 00007ff7a844af91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000800000009 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff7a861f128 R14: 00007ff7a861f090 R15: 00007ffdef53f598
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/07 23:07 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 sendfile64
* Struck through repros no longer work on HEAD.