INFO: task syz.3.19:6894 blocked for more than 143 seconds. Not tainted 6.15.0-rc6-syzkaller-g9f35e33144ae #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.19 state:D stack:28344 pid:6894 tgid:6893 ppid:6634 task_flags:0x400040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1578 inode_lock include/linux/fs.h:867 [inline] blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 vfs_fallocate+0x6a0/0x830 fs/open.c:338 ksys_fallocate fs/open.c:362 [inline] __do_sys_fallocate fs/open.c:367 [inline] __se_sys_fallocate fs/open.c:365 [inline] __x64_sys_fallocate+0xc0/0x110 fs/open.c:365 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7e04185d29 RSP: 002b:00007f7e05095038 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007f7e04375fa0 RCX: 00007f7e04185d29 RDX: 0000000000000000 RSI: 0000000000000011 RDI: 0000000000000004 RBP: 00007f7e04201aa8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000001000074000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f7e04375fa0 R15: 00007ffcfdbc0c88 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 3 locks held by kworker/u8:6/3423: #0: ffff8880b8839b58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605 #1: ffffc9000c6d7c60 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000c6d7c60 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #2: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #2: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] #2: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: batadv_nc_worker+0xd2/0x610 net/batman-adv/network-coding.c:719 3 locks held by kworker/u8:8/3531: #0: ffff88802f9dc948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88802f9dc948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000cac7c60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000cac7c60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8f2f72c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f2f72c8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4198 2 locks held by getty/5596: #0: ffff88803432a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002ffe2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 4 locks held by syz.2.18/6892: 1 lock held by syz.3.19/6894: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.0.16/6896: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.4.20/6898: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.5.21/7423: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.8.24/7436: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.7.23/7439: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.6.22/7441: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.9.25/7443: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.1.26/7496: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.2.27/7534: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.4.30/7546: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.0.29/7553: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.3.28/7557: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.5.31/7572: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.8.32/7616: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.6.33/7649: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.7.34/7679: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.9.35/7687: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.1.36/7689: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.2.37/7700: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.4.38/7725: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 3 locks held by syz-executor/7737: #0: ffffffff8f2f72c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f2f72c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8f2f72c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4064 #1: ffff8880752e14e8 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_open+0x227/0x420 drivers/net/wireguard/device.c:50 #2: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #2: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998 1 lock held by syz-executor/7754: #0: ffffffff8f2f72c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f2f72c8 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x5b7/0xd20 net/ipv6/addrconf.c:5031 7 locks held by syz-executor/7767: #0: ffff888034716420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #0: ffff888034716420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:680 #1: ffff88807d937488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325 #2: ffff888144bc92d8 (kn->active#59){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326 #3: ffffffff8eb96f28 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x12c/0x6f0 drivers/net/netdevsim/bus.c:166 #4: ffff88806fa2f0e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #4: ffff88806fa2f0e8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1004 #5: ffff8880207e9250 (&devlink->lock_key#31){+.+.}-{4:4}, at: nsim_drv_probe+0xc1/0xb70 drivers/net/netdevsim/dev.c:1537 #6: ffffffff8f2f72c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #6: ffffffff8f2f72c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0 net/core/dev.c:2089 1 lock held by syz.3.39/7778: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 1 lock held by syz.0.40/7797: #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c97aa0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:853 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-g9f35e33144ae #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6892 Comm: syz.2.18 Not tainted 6.15.0-rc6-syzkaller-g9f35e33144ae #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:memset_orig+0x15/0xb0 arch/x86/lib/memset_64.S:56 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 01 01 48 0f af c1 <41> 89 f9 41 83 e1 07 75 74 48 89 d1 48 c1 e9 06 74 39 66 0f 1f 84 RSP: 0018:ffffc90003e0f030 EFLAGS: 00000206 RAX: 0000000000000000 RBX: ffffc90003e0f140 RCX: 0000000000000000 RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc90003e0f158 RBP: dffffc0000000000 R08: ffffc90003e0f167 R09: 1ffff920007c1e2c R10: ffffc90003e0f158 R11: fffff520007c1e2d R12: ffffc90003e0f240 R13: ffffc90003e0f158 R14: ffffc90003e0f108 R15: ffffc90003e0f150 FS: 00007fac3f7686c0(0000) GS:ffff8881260c7000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3c3ba13000 CR3: 0000000061cea000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0xc98/0x2390 arch/x86/kernel/unwind_orc.c:592 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4147 [inline] slab_alloc_node mm/slub.c:4196 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4203 mempool_alloc_noprof+0x1a7/0x510 mm/mempool.c:402 bio_alloc_bioset+0x241/0x1110 block/bio.c:554 bio_alloc_clone block/bio.c:864 [inline] bio_split+0x110/0x4a0 block/bio.c:1587 bio_submit_split+0x96/0x5e0 block/blk-merge.c:116 __bio_split_to_limits block/blk.h:393 [inline] blk_mq_submit_bio+0x171a/0x2240 block/blk-mq.c:3110 __submit_bio+0x207/0x5a0 block/blk-core.c:635 __submit_bio_noacct_mq block/blk-core.c:722 [inline] submit_bio_noacct_nocheck+0x50b/0xb50 block/blk-core.c:751 bio_chain_and_submit+0xeb/0x130 block/bio.c:361 __blkdev_issue_zero_pages+0x223/0x2a0 block/blk-lib.c:222 blkdev_issue_zero_pages block/blk-lib.c:238 [inline] blkdev_issue_zeroout+0x56c/0x7c0 block/blk-lib.c:325 blkdev_fallocate+0x3e6/0x4b0 block/fops.c:-1 vfs_fallocate+0x6a0/0x830 fs/open.c:338 ksys_fallocate fs/open.c:362 [inline] __do_sys_fallocate fs/open.c:367 [inline] __se_sys_fallocate fs/open.c:365 [inline] __x64_sys_fallocate+0xc0/0x110 fs/open.c:365 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fac3e985d29 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:00007fac3f768038 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007fac3eb75fa0 RCX: 00007fac3e985d29 RDX: 0000000000000000 RSI: 0000000000000011 RDI: 0000000000000004 RBP: 00007fac3ea01aa8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000001000074000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fac3eb75fa0 R15: 00007ffc210bd328