syzbot


WARNING in rcu_tasks_verify_work_fn

Status: upstream: reported on 2026/03/31 21:53
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+251e9abcdac140e7ec74@syzkaller.appspotmail.com
First crash: 4d17h, last: 4d17h
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [kernel?] WARNING in rcu_tasks_verify_work_fn 0 (1) 2026/03/31 21:53

Sample crash report:
cpu1: Ratio of byte access time to unaligned word access is 7.19, unaligned accesses are fast
hrtimer: interrupt took 78219600 ns
------------[ cut here ]------------
WARNING: [ret < 0] kernel/rcu/tasks.h:1530 at rcu_tasks_verify_self_tests kernel/rcu/tasks.h:1520 [inline], CPU#1: swapper/0/1
WARNING: [ret < 0] kernel/rcu/tasks.h:1530 at rcu_tasks_verify_work_fn+0x27e/0x31c kernel/rcu/tasks.h:1542, CPU#1: swapper/0/1
Modules linked in:
CPU: 1 UID: 0 PID: 1 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT 
Hardware name: riscv-virtio,qemu (DT)
epc : rcu_tasks_verify_self_tests kernel/rcu/tasks.h:1530 [inline]
epc : rcu_tasks_verify_work_fn+0x27e/0x31c kernel/rcu/tasks.h:1542
 ra : rcu_tasks_verify_self_tests kernel/rcu/tasks.h:1522 [inline]
 ra : rcu_tasks_verify_work_fn+0x250/0x31c kernel/rcu/tasks.h:1542
epc : ffffffff8036ee1e ra : ffffffff8036edf0 sp : ffff8f8000027b10
 gp : ffffffff8a229d40 tp : ffffaf8012afcf80 t0 : 1ffffffff22c0085
 t1 : ffffffff8007a85c t2 : ffffffff91600428 s0 : ffff8f8000027bb0
 s1 : 0000000000000bb8 a0 : ffffffff887f4a40 a1 : 0000000000000000
 a2 : 0000000000000002 a3 : ffffffff803213b0 a4 : 1ffffffff10fe948
 a5 : 0000000000000000 a6 : 0000000000000003 a7 : 0000000041b58ab3
 s2 : 1ffff1f000004f64 s3 : ffff8f8000027b60 s4 : ffff8f8000027ca0
 s5 : ffffffff88614240 s6 : ffffffff887f5060 s7 : 0000000000000000
 s8 : 1ffffffff1467758 s9 : 0000000000000000 s10: ffffffff8a33bac0
 s11: ffffffff881b2cf0 t3 : ffffffff87fb27e0 t4 : fffff5ef0e594511
 t5 : fffff5ef0e594512 t6 : ffffffff86878840 ssp : 0000000000000000
status: 0000000200000120 badaddr: ffffffff8036ee1e cause: 0000000000000003
[<ffffffff8036ee1e>] rcu_tasks_verify_self_tests kernel/rcu/tasks.h:1520 [inline]
[<ffffffff8036ee1e>] rcu_tasks_verify_work_fn+0x27e/0x31c kernel/rcu/tasks.h:1542
[<ffffffff8036ef58>] rcu_tasks_verify_schedule_work+0x9c/0xa8 kernel/rcu/tasks.h:1554
[<ffffffff80063e4c>] do_one_initcall+0x18c/0xcdc init/main.c:1382
[<ffffffff86602d5a>] do_initcall_level init/main.c:1444 [inline]
[<ffffffff86602d5a>] do_initcalls init/main.c:1460 [inline]
[<ffffffff86602d5a>] do_basic_setup init/main.c:1479 [inline]
[<ffffffff86602d5a>] kernel_init_freeable+0x6ca/0x7b0 init/main.c:1692
[<ffffffff86433d40>] kernel_init+0x28/0x240 init/main.c:1582
[<ffffffff80069138>] ret_from_fork_kernel+0x94/0xef8 arch/riscv/kernel/process.c:228
[<ffffffff86459d52>] ret_from_fork_kernel_asm+0x16/0x18 arch/riscv/kernel/entry.S:363

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/27 22:12 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next b335bc5892a0 158c21af .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 WARNING in rcu_tasks_verify_work_fn
2026/03/27 21:42 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next b335bc5892a0 158c21af .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 WARNING in rcu_tasks_verify_work_fn
2026/03/27 21:42 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next b335bc5892a0 158c21af .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 WARNING in rcu_tasks_verify_work_fn
* Struck through repros no longer work on HEAD.