INFO: task syz.9.624:12618 blocked for more than 143 seconds. Not tainted 6.15.0-rc6-syzkaller-00208-g3c21441eeffc #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.9.624 state:D stack:23720 pid:12618 tgid:12617 ppid:11151 task_flags:0x440140 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 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_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526 filemap_invalidate_lock_shared include/linux/fs.h:922 [inline] page_cache_ra_order+0x445/0xc70 mm/readahead.c:491 filemap_get_pages+0x43c/0x1eb0 mm/filemap.c:2591 filemap_splice_read+0x4fc/0xbc0 mm/filemap.c:2981 do_splice_read fs/splice.c:979 [inline] splice_direct_to_actor+0x4a9/0xcc0 fs/splice.c:1083 do_splice_direct_actor fs/splice.c:1201 [inline] do_splice_direct+0x181/0x270 fs/splice.c:1227 do_sendfile+0x4da/0x7d0 fs/read_write.c:1368 __do_sys_sendfile64 fs/read_write.c:1429 [inline] __se_sys_sendfile64+0x13e/0x190 fs/read_write.c:1415 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: 0033:0x7fe64a78e969 RSP: 002b:00007fe64b575038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007fe64a9b5fa0 RCX: 00007fe64a78e969 RDX: 0000000000000000 RSI: 0000000000000007 RDI: 0000000000000004 RBP: 00007fe64a810ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000fffe82 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fe64a9b5fa0 R15: 00007ffc6cfa2c68 Showing all locks held in the system: 4 locks held by kworker/u8:0/12: 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/u8:3/53: #0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc90000be7c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000be7c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8f2e4fc8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 3 locks held by kworker/u8:5/69: #0: ffff88814d2f7948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88814d2f7948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000158fc60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000158fc60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8f2e4fc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f2e4fc8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4198 2 locks held by dhcpcd/5484: #0: ffffffff8f2c9a88 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x5ee/0x790 net/socket.c:1273 #1: ffffffff8f2e4fc8 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0xd0/0x650 net/8021q/vlan.c:554 2 locks held by getty/5577: #0: ffff888030ac10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by syz.3.606/12369: 1 lock held by syz.9.624/12618: #0: ffff88802285fc40 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:922 [inline] #0: ffff88802285fc40 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x445/0xc70 mm/readahead.c:491 1 lock held by syz.2.811/14602: #0: ffff88802285faa0 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:877 [inline] #0: ffff88802285faa0 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_read_iter+0x2f8/0x440 block/fops.c:808 1 lock held by syz.1.834/14788: #0: ffff88802285fc40 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:922 [inline] #0: ffff88802285fc40 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x445/0xc70 mm/readahead.c:491 1 lock held by syz-executor/14833: #0: ffffffff8f2e4fc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f2e4fc8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:979 2 locks held by syz-executor/14952: #0: ffffffff8ea7ea20 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ea7ea20 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8ea7ea20 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8f2e4fc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f2e4fc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8f2e4fc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4064 1 lock held by syz-executor/14991: #0: ffffffff8f2e4fc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f2e4fc8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:979 1 lock held by syz.6.859/15055: #0: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #0: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-00208-g3c21441eeffc #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+0x70e/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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 12369 Comm: syz.3.606 Not tainted 6.15.0-rc6-syzkaller-00208-g3c21441eeffc #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210 Code: 89 fb e8 23 00 00 00 48 8b 3d 5c c3 d5 0b 48 89 de 5b e9 33 41 55 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 70 72 92 65 8b 15 18 7f RSP: 0018:ffffc90004ff7440 EFLAGS: 00000287 RAX: ffffffff849603be RBX: ffff8880244f5600 RCX: 0000000000000002 RDX: ffff88802eb7da00 RSI: 0000000000000040 RDI: 0000000000000018 RBP: 0000000000000040 R08: ffff888025072497 R09: 1ffff11004a0e492 R10: dffffc0000000000 R11: ffffed1004a0e493 R12: 0000000000000000 R13: dffffc0000000000 R14: ffffe8ffffd0f840 R15: 0000000000000018 FS: 00007f7d8b64d6c0(0000) GS:ffff8881261f9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055e107c8dfb0 CR3: 000000007be60000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: blk_mq_put_tag+0x8c/0x120 block/blk-mq-tag.c:231 __blk_mq_free_request+0x2fb/0x430 block/blk-mq.c:778 nullb_complete_cmd drivers/block/null_blk/main.c:1402 [inline] null_handle_cmd drivers/block/null_blk/main.c:1454 [inline] null_queue_rq+0xbfe/0xe30 drivers/block/null_blk/main.c:1693 null_queue_rqs+0x123/0x270 drivers/block/null_blk/main.c:1707 __blk_mq_flush_plug_list block/blk-mq.c:2825 [inline] blk_mq_flush_plug_list+0x586/0x1760 block/blk-mq.c:2904 blk_add_rq_to_plug+0x175/0x450 block/blk-mq.c:1384 blk_mq_submit_bio+0xd78/0x2240 block/blk-mq.c:3156 __submit_bio+0x207/0x5a0 block/blk-core.c:635 __submit_bio_noacct_mq block/blk-core.c:722 [inline] submit_bio_noacct_nocheck+0x4b1/0xb50 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: 0033:0x7f7d8a78e969 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:00007f7d8b64d038 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007f7d8a9b5fa0 RCX: 00007f7d8a78e969 RDX: 0000000080000000 RSI: 0000000000000011 RDI: 0000000000000003 RBP: 00007f7d8a810ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0140000904000004 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f7d8a9b5fa0 R15: 00007ffd612de978