syzbot


INFO: task hung in synchronize_rcu

Status: internal: reported on 2025/07/11 21:20
Reported-by: syzbot+0232e02d8636b4ed7022@syzkaller.appspotmail.com
First crash: 124d, last: 13h03m
Similar bugs (13)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in synchronize_rcu (3) 1 C done done 374 984d 1921d 22/29 fixed on 2023/02/24 13:50
linux-6.1 INFO: task hung in synchronize_rcu origin:lts-only 1 C unreliable 24 38d 939d 0/3 upstream: reported C repro on 2023/04/01 04:49
android-49 INFO: task hung in synchronize_rcu 1 1 2157d 2157d 0/3 auto-closed as invalid on 2020/03/28 16:57
linux-4.14 INFO: task hung in synchronize_rcu vfs 1 C error 162 998d 2180d 0/1 upstream: reported C repro on 2019/11/07 04:32
linux-4.19 INFO: task hung in synchronize_rcu 1 C error 70 987d 2178d 0/1 upstream: reported C repro on 2019/11/08 21:27
linux-5.15 INFO: task hung in synchronize_rcu 1 1 924d 924d 0/3 auto-obsoleted due to no activity on 2023/08/14 02:05
linux-5.15 INFO: task hung in synchronize_rcu (3) origin:lts-only 1 C error 14 12d 457d 0/3 upstream: reported C repro on 2024/07/26 03:55
upstream INFO: task hung in synchronize_rcu 1 syz done 1206 2157d 2183d 14/29 fixed on 2019/11/29 15:48
upstream INFO: task hung in synchronize_rcu (4) fs net 1 C done error 1490 1h30m 906d 0/29 upstream: reported C repro on 2023/05/04 02:01
linux-5.15 INFO: task hung in synchronize_rcu (2) 1 1 612d 612d 0/3 auto-obsoleted due to no activity on 2024/05/31 13:53
android-414 INFO: task hung in synchronize_rcu 1 1 2175d 2175d 0/1 auto-closed as invalid on 2020/03/10 10:42
upstream INFO: task hung in synchronize_rcu (2) trace 1 8 2156d 2157d 0/29 closed as invalid on 2019/11/30 16:54
upstream INFO: task hung in rtnetlink_rcv_msg net 1 C inconclusive inconclusive 1970 474d 2437d 26/29 fixed on 2024/07/09 19:14

Sample crash report:
INFO: task kworker/0:0:9 blocked for more than 122 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:0     state:D
 stack:0     pid:9     tgid:9     ppid:2      flags:0x00004000
Workqueue: events _RNvXs6_NtCs43vyB533jt3_6kernel9workqueueINtNtNtB7_4sync3arc3ArcNtNtCs5gLWsBERDPK_16rust_binder_main7process7ProcessEINtB5_15WorkItemPointerKy0_E3runB13_

Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5945 [inline]
 __schedule+0x1322/0x1df0 kernel/sched/core.c:7791
 __schedule_loop kernel/sched/core.c:7872 [inline]
 schedule+0xc6/0x240 kernel/sched/core.c:7887
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
 exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline]
 synchronize_rcu_expedited+0x288/0x7b0 kernel/rcu/tree_exp.h:976
 synchronize_rcu+0x77/0x2e0 kernel/rcu/tree.c:4119
 core::ptr::drop_in_place::<kernel::sync::poll::PollCondVar> usr/local/rustup/toolchains/1.87.0-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ptr/mod.rs:523 [inline]
 core::ptr::drop_in_place::<rust_binder_main::thread::Thread> usr/local/rustup/toolchains/1.87.0-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ptr/mod.rs:523 [inline]
 core::ptr::drop_in_place::<kernel::sync::arc::ArcInner<rust_binder_main::thread::Thread>> usr/local/rustup/toolchains/1.87.0-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ptr/mod.rs:523 [inline]
 <kernel::alloc::kbox::Box<kernel::sync::arc::ArcInner<rust_binder_main::thread::Thread>, kernel::alloc::allocator::Kmalloc> as core::ops::drop::Drop>::drop rust/kernel/alloc/kbox.rs:487 [inline]
 core::ptr::drop_in_place::<kernel::alloc::kbox::Box<kernel::sync::arc::ArcInner<rust_binder_main::thread::Thread>, kernel::alloc::allocator::Kmalloc>>+0x2ab/0x340 usr/local/rustup/toolchains/1.87.0-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ptr/mod.rs:523
 core::mem::drop::<kernel::alloc::kbox::Box<kernel::sync::arc::ArcInner<rust_binder_main::thread::Thread>, kernel::alloc::allocator::Kmalloc>> usr/local/rustup/toolchains/1.87.0-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/mem/mod.rs:935 [inline]
 <kernel::sync::arc::Arc<rust_binder_main::thread::Thread> as core::ops::drop::Drop>::drop rust/kernel/sync/arc.rs:404 [inline]
 core::ptr::drop_in_place::<kernel::sync::arc::Arc<rust_binder_main::thread::Thread>> usr/local/rustup/toolchains/1.87.0-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ptr/mod.rs:523 [inline]
 core::ptr::drop_in_place::<kernel::rbtree::Node<i32, kernel::sync::arc::Arc<rust_binder_main::thread::Thread>>> usr/local/rustup/toolchains/1.87.0-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ptr/mod.rs:523 [inline]
 <kernel::alloc::kbox::Box<kernel::rbtree::Node<i32, kernel::sync::arc::Arc<rust_binder_main::thread::Thread>>, kernel::alloc::allocator::Kmalloc> as core::ops::drop::Drop>::drop rust/kernel/alloc/kbox.rs:487 [inline]
 core::ptr::drop_in_place::<kernel::alloc::kbox::Box<kernel::rbtree::Node<i32, kernel::sync::arc::Arc<rust_binder_main::thread::Thread>>, kernel::alloc::allocator::Kmalloc>> usr/local/rustup/toolchains/1.87.0-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ptr/mod.rs:523 [inline]
 core::mem::drop::<kernel::alloc::kbox::Box<kernel::rbtree::Node<i32, kernel::sync::arc::Arc<rust_binder_main::thread::Thread>>, kernel::alloc::allocator::Kmalloc>> usr/local/rustup/toolchains/1.87.0-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/mem/mod.rs:935 [inline]
 <kernel::rbtree::RBTree<i32, kernel::sync::arc::Arc<rust_binder_main::thread::Thread>> as core::ops::drop::Drop>::drop rust/kernel/rbtree.rs:499 [inline]
 core::ptr::drop_in_place::<kernel::rbtree::RBTree<i32, kernel::sync::arc::Arc<rust_binder_main::thread::Thread>>>+0xc5/0x190 usr/local/rustup/toolchains/1.87.0-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ptr/mod.rs:523
 core::mem::drop::<kernel::rbtree::RBTree<i32, kernel::sync::arc::Arc<rust_binder_main::thread::Thread>>> usr/local/rustup/toolchains/1.87.0-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/mem/mod.rs:935 [inline]
 <rust_binder_main::process::Process>::deferred_release drivers/android/binder/process.rs:1406 [inline]
 <rust_binder_main::process::Process as kernel::workqueue::WorkItem>::run+0x244b/0x2820 drivers/android/binder/process.rs:505
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x7d2/0x1020 kernel/workqueue.c:3319
 worker_thread+0xc58/0x1250 kernel/workqueue.c:3400
 kthread+0x2ca/0x370 kernel/kthread.c:389
 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
INFO: task kworker/0:2:66 blocked for more than 123 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:2     state:I
 stack:0     pid:66    tgid:66    ppid:2      flags:0x00004000
Workqueue:  0x0
 (events)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5945 [inline]
 __schedule+0x1322/0x1df0 kernel/sched/core.c:7791
 __schedule_loop kernel/sched/core.c:7872 [inline]
 schedule+0xc6/0x240 kernel/sched/core.c:7887
 worker_thread+0xf6b/0x1250 kernel/workqueue.c:3415
 kthread+0x2ca/0x370 kernel/kthread.c:389
 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
INFO: task jbd2/sda1-8:73 blocked for more than 123 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:jbd2/sda1-8     state:D
 stack:0     pid:73    tgid:73    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5945 [inline]
 __schedule+0x1322/0x1df0 kernel/sched/core.c:7791
 __schedule_loop kernel/sched/core.c:7872 [inline]
 schedule+0xc6/0x240 kernel/sched/core.c:7887
 io_schedule+0x89/0xe0 kernel/sched/core.c:8699
 bit_wait_io+0x17/0xd0 kernel/sched/wait_bit.c:209
 __wait_on_bit+0xc1/0x2e0 kernel/sched/wait_bit.c:49
 out_of_line_wait_on_bit+0x121/0x170 kernel/sched/wait_bit.c:64
 wait_on_bit_io include/linux/wait_bit.h:101 [inline]
 __wait_on_buffer+0x5a/0x70 fs/buffer.c:123
 wait_on_buffer include/linux/buffer_head.h:422 [inline]
 journal_wait_on_commit_record fs/jbd2/commit.c:171 [inline]
 jbd2_journal_commit_transaction+0x3450/0x5460 fs/jbd2/commit.c:887
 kjournald2+0x3a3/0x6a0 fs/jbd2/journal.c:201
 kthread+0x2ca/0x370 kernel/kthread.c:389
 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
INFO: task syz.0.119:727 blocked for more than 124 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.119       state:D
 stack:0     pid:727   tgid:727   ppid:290    flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5945 [inline]
 __schedule+0x1322/0x1df0 kernel/sched/core.c:7791
 __schedule_loop kernel/sched/core.c:7872 [inline]
 schedule+0xc6/0x240 kernel/sched/core.c:7887
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
 rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
 ip_mc_drop_socket+0x7a/0x370 net/ipv4/igmp.c:2702
 inet_release+0xa5/0x2c0 net/ipv4/af_inet.c:429
 __sock_release net/socket.c:659 [inline]
 sock_close+0xdd/0x280 net/socket.c:1427
 __fput+0x1fb/0xa00 fs/file_table.c:429
 ____fput+0x20/0x30 fs/file_table.c:457
 task_work_run+0x1e0/0x250 kernel/task_work.c:240
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0x9bc/0x2630 kernel/exit.c:953
 do_group_exit+0x22a/0x300 kernel/exit.c:1095
 get_signal+0x139d/0x14f0 kernel/signal.c:2933
 arch_do_signal_or_restart+0x96/0x720 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x58/0xb0 kernel/entry/common.c:218
 do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fb2259c1885
RSP: 002b:00007fb2268d7f80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007fb225be5fa0 RCX: 00007fb2259c1885
RDX: 00007fb2268d7fc0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fb225a11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007fb225be6038 R14: 00007fb225be5fa0 R15: 00007ffde10f4598
 </TASK>
INFO: task syz-executor:1866 blocked for more than 126 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:1866  tgid:1866  ppid:1      flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5945 [inline]
 __schedule+0x1322/0x1df0 kernel/sched/core.c:7791
 __schedule_loop kernel/sched/core.c:7872 [inline]
 schedule+0xc6/0x240 kernel/sched/core.c:7887
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
 rtnl_lock net/core/rtnetlink.c:79 [inline]
 rtnetlink_rcv_msg+0x75f/0xa00 net/core/rtnetlink.c:6675
 netlink_rcv_skb+0x22b/0x4a0 net/netlink/af_netlink.c:2545
 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x7f0/0xaf0 net/netlink/af_netlink.c:1889
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 __sys_sendto+0x66d/0x6f0 net/socket.c:2217
 __do_sys_sendto net/socket.c:2229 [inline]
 __se_sys_sendto net/socket.c:2225 [inline]
 __x64_sys_sendto+0xe9/0x100 net/socket.c:2225
 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fc912990e03
RSP: 002b:00007fff54b35948 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fc913714620 RCX: 00007fc912990e03
RDX: 0000000000000028 RSI: 00007fc913714670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007fff54b35964 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fc913714670 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:1869 blocked for more than 126 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:1869  tgid:1869  ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5945 [inline]
 __schedule+0x1322/0x1df0 kernel/sched/core.c:7791
 __schedule_loop kernel/sched/core.c:7872 [inline]
 schedule+0xc6/0x240 kernel/sched/core.c:7887
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
 rtnl_lock net/core/rtnetlink.c:79 [inline]
 rtnetlink_rcv_msg+0x75f/0xa00 net/core/rtnetlink.c:6675
 netlink_rcv_skb+0x22b/0x4a0 net/netlink/af_netlink.c:2545
 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x7f0/0xaf0 net/netlink/af_netlink.c:1889
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 __sys_sendto+0x66d/0x6f0 net/socket.c:2217
 __do_sys_sendto net/socket.c:2229 [inline]
 __se_sys_sendto net/socket.c:2225 [inline]
 __x64_sys_sendto+0xe9/0x100 net/socket.c:2225
 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f9ced190e03
RSP: 002b:00007fff8c92c798 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f9cedf14620 RCX: 00007f9ced190e03
RDX: 0000000000000028 RSI: 00007f9cedf14670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007fff8c92c7b4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f9cedf14670 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:1872 blocked for more than 127 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:1872  tgid:1872  ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5945 [inline]
 __schedule+0x1322/0x1df0 kernel/sched/core.c:7791
 __schedule_loop kernel/sched/core.c:7872 [inline]
 schedule+0xc6/0x240 kernel/sched/core.c:7887
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
 rtnl_lock net/core/rtnetlink.c:79 [inline]
 rtnetlink_rcv_msg+0x75f/0xa00 net/core/rtnetlink.c:6675
 netlink_rcv_skb+0x22b/0x4a0 net/netlink/af_netlink.c:2545
 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x7f0/0xaf0 net/netlink/af_netlink.c:1889
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 __sys_sendto+0x66d/0x6f0 net/socket.c:2217
 __do_sys_sendto net/socket.c:2229 [inline]
 __se_sys_sendto net/socket.c:2225 [inline]
 __x64_sys_sendto+0xe9/0x100 net/socket.c:2225
 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fc6e9b90e03
RSP: 002b:00007ffccb4cb938 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fc6ea914620 RCX: 00007fc6e9b90e03
RDX: 0000000000000028 RSI: 00007fc6ea914670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffccb4cb954 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fc6ea914670 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:1873 blocked for more than 127 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:R  running task     stack:0     pid:1873  tgid:1873  ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5945 [inline]
 __schedule+0x1322/0x1df0 kernel/sched/core.c:7791
 __schedule_loop kernel/sched/core.c:7872 [inline]
 schedule+0xc6/0x240 kernel/sched/core.c:7887
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
 rtnl_lock net/core/rtnetlink.c:79 [inline]
 rtnetlink_rcv_msg+0x75f/0xa00 net/core/rtnetlink.c:6675
 netlink_rcv_skb+0x22b/0x4a0 net/netlink/af_netlink.c:2545
 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x7f0/0xaf0 net/netlink/af_netlink.c:1889
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 __sys_sendto+0x66d/0x6f0 net/socket.c:2217
 __do_sys_sendto net/socket.c:2229 [inline]
 __se_sys_sendto net/socket.c:2225 [inline]
 __x64_sys_sendto+0xe9/0x100 net/socket.c:2225
 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fc1f3790e03
RSP: 002b:00007fff0e3a71b8 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fc1f4514620 RCX: 00007fc1f3790e03
RDX: 0000000000000028 RSI: 00007fc1f4514670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007fff0e3a71d4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fc1f4514670 R15: 0000000000000000
 </TASK>
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 nmi_cpu_backtrace+0x2bf/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
 watchdog+0xd8f/0xed0 kernel/hung_task.c:423
 kthread+0x2ca/0x370 kernel/kthread.c:389
 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 1866 Comm: syz-executor Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:arch_stack_walk+0x110/0x170 arch/x86/kernel/stacktrace.c:27
Code: ff ff 4c 89 e6 4c 89 fa e8 3d 9a 06 00 83 bd 78 ff ff ff 00 74 46 4c 8d bd 78 ff ff ff 4c 89 ff e8 f5 89 06 00 48 85 c0 74 32 <48> 89 df 48 89 c6 4d 89 f3 41 ba aa 37 f9 9e 45 03 53 f1 74 02 0f
RSP: 0018:ffffc9000114f428 EFLAGS: 00000282
RAX: ffffffff81d5689d RBX: ffffc9000114f4e0 RCX: 000000000114f400
RDX: ffffc9000114f701 RSI: 1ffff92000229e86 RDI: ffffffff81d5689d
RBP: ffffc9000114f4b0 R08: ffffc9000114f4f0 R09: ffffc9000114f4e8
R10: 0000000000000000 R11: ffffffff817457d0 R12: ffff888114011300
R13: 1ffff92000229eb0 R14: ffffffff817457d0 R15: ffffc9000114f428
FS:  0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561281c2f8f0 CR3: 00000000072a8000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 stack_trace_save+0x9d/0xe0 kernel/stacktrace.c:122
 save_stack+0xf8/0x1f0 mm/page_owner.c:174
 __reset_page_owner+0x79/0x450 mm/page_owner.c:315
 reset_page_owner include/linux/page_owner.h:28 [inline]
 free_pages_prepare mm/page_alloc.c:1352 [inline]
 free_unref_page+0xb4d/0xee0 mm/page_alloc.c:2842
 __free_pages+0x6b/0x3b0 mm/page_alloc.c:5351
 vfree+0x3bf/0x580 mm/vmalloc.c:3396
 kcov_put kernel/kcov.c:439 [inline]
 kcov_close+0x2c/0x70 kernel/kcov.c:535
 __fput+0x1fb/0xa00 fs/file_table.c:429
 ____fput+0x20/0x30 fs/file_table.c:457
 task_work_run+0x1e0/0x250 kernel/task_work.c:240
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0x9bc/0x2630 kernel/exit.c:953
 do_group_exit+0x22a/0x300 kernel/exit.c:1095
 get_signal+0x139d/0x14f0 kernel/signal.c:2933
 arch_do_signal_or_restart+0x96/0x720 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x58/0xb0 kernel/entry/common.c:218
 do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fc912990e03
Code: Unable to access opcode bytes at 0x7fc912990dd9.
RSP: 002b:00007fff54b35948 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: 0000000000000028 RBX: 00007fc913714620 RCX: 00007fc912990e03
RDX: 0000000000000028 RSI: 00007fc913714670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007fff54b35964 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fc913714670 R15: 0000000000000000
 </TASK>

Crashes (35):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/25 19:29 android16-6.12 0d6730ee6542 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/09/22 02:25 android16-6.12 8419b8c58fd1 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/09/21 13:02 android16-6.12 8419b8c58fd1 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/09/08 07:01 android16-6.12 ad3375325ca2 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/09/05 08:16 android16-6.12 c5058bfb5bf2 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/09/03 21:13 android16-6.12 53e4390f692f 96a211bc .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/09/03 13:02 android16-6.12 53e4390f692f 96a211bc .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/09/03 07:03 android16-6.12 4ae522d0f966 96a211bc .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/09/03 00:41 android16-6.12 4ae522d0f966 96a211bc .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/08/31 15:49 android16-6.12 6879524e1c5a 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/08/29 14:23 android16-6.12 cbb0a15dcc1e 3e1beec6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/08/28 20:00 android16-6.12 cbb0a15dcc1e d401b9d7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/08/28 02:44 android16-6.12 c17d1926681a e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/08/10 15:52 android16-6.12 d0c633175c04 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/08/08 08:40 android16-6.12 209015b548fb 6a893178 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/08/06 04:02 android16-6.12 78c6c49396da ffe1dd46 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/08/02 02:42 android16-6.12 bf0fb8bb181b 7368264b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/08/01 23:52 android16-6.12 bf0fb8bb181b 7368264b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/07/27 13:59 android16-6.12 e9bbc29c066a fb8f743d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/07/23 16:19 android16-6.12 fc2476d0896a e1dd4f22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/07/22 07:02 android16-6.12 2199f5c4b596 1555463b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/07/22 06:27 android16-6.12 2199f5c4b596 1555463b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/07/22 00:07 android16-6.12 25f19cb85021 56d87229 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/07/15 19:24 android16-6.12 603af016e4a8 03fcfc4b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/07/12 20:23 android16-6.12 21ed84930c16 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/07/12 13:03 android16-6.12 21ed84930c16 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/07/11 00:05 android16-6.12 8ea40f524391 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/07/10 10:32 android16-6.12 d893caf112c8 956bd956 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/07/08 17:41 android16-6.12 15d2fe054444 4d9fdfa4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/07/08 10:31 android16-6.12 f6ca783ba264 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/07/07 00:11 android16-6.12 e2bf362ee23b 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/07/04 17:24 android16-6.12 e2bf362ee23b d869b261 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/07/03 23:49 android16-6.12 e2bf362ee23b 76ad128c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/07/02 06:25 android16-6.12 c40c54e66959 bc80e4f0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
2025/06/24 05:10 android16-6.12 1d4f4d446dbd e2f27c35 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in synchronize_rcu
* Struck through repros no longer work on HEAD.