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INFO: task hung in filemap_page_mkwrite (2)

Status: auto-obsoleted due to no activity on 2026/02/26 15:05
Subsystems: mm
[Documentation on labels]
First crash: 94d, last: 94d
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in filemap_page_mkwrite fs 1 1 811d 811d 0/29 auto-obsoleted due to no activity on 2024/03/12 03:45

Sample crash report:
INFO: task syz.1.4280:19603 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.4280      state:D stack:25480 pid:19603 tgid:19601 ppid:19256  task_flags:0x400040 flags:0x00080003
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7026
 io_schedule+0x81/0xe0 kernel/sched/core.c:7871
 folio_wait_bit_common+0x6b5/0xb90 mm/filemap.c:1330
 __folio_lock mm/filemap.c:1706 [inline]
 folio_lock include/linux/pagemap.h:1141 [inline]
 filemap_page_mkwrite+0x2fb/0x6d0 mm/filemap.c:3894
 do_page_mkwrite+0x150/0x310 mm/memory.c:3489
 do_shared_fault mm/memory.c:5792 [inline]
 do_fault mm/memory.c:5854 [inline]
 do_pte_missing mm/memory.c:4362 [inline]
 handle_pte_fault mm/memory.c:6195 [inline]
 __handle_mm_fault mm/memory.c:6336 [inline]
 handle_mm_fault+0x124b/0x3400 mm/memory.c:6505
 faultin_page mm/gup.c:1126 [inline]
 __get_user_pages+0x1685/0x2860 mm/gup.c:1428
 __get_user_pages_locked mm/gup.c:1752 [inline]
 faultin_page_range+0x44b/0x8d0 mm/gup.c:1912
 madvise_populate mm/madvise.c:979 [inline]
 madvise_do_behavior+0x2e7/0x550 mm/madvise.c:1883
 do_madvise+0x183/0x230 mm/madvise.c:1978
 __do_sys_madvise mm/madvise.c:1987 [inline]
 __se_sys_madvise mm/madvise.c:1985 [inline]
 __x64_sys_madvise+0xa7/0xc0 mm/madvise.c:1985
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff9497df749
RSP: 002b:00007ff947a25038 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
RAX: ffffffffffffffda RBX: 00007ff949a36090 RCX: 00007ff9497df749
RDX: 0000000000000017 RSI: 0000000000600000 RDI: 0000200000000000
RBP: 00007ff949863f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff949a36128 R14: 00007ff949a36090 R15: 00007ffe64ca8738
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/38:
 #0: ffffffff8d5aa880 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8d5aa880 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
 #0: ffffffff8d5aa880 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
8 locks held by kworker/u8:8/1160:
2 locks held by dhcpcd/5465:
 #0: ffff8880320f2920 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: netlink_dump+0xbd/0xe90 net/netlink/af_netlink.c:2269
 #1: ffffffff8e863af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #1: ffffffff8e863af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6819
2 locks held by getty/5558:
 #0: ffff88823bf7a8a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000418b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1400 drivers/tty/n_tty.c:2222
3 locks held by kworker/u8:14/6179:
 #0: ffff88814d016138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
 #0: ffff88814d016138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
 #1: ffffc9000c287ba0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
 #1: ffffc9000c287ba0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
 #2: ffffffff8e863af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #2: ffffffff8e863af8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x119/0x15a0 net/ipv6/addrconf.c:4194
2 locks held by syz.1.4280/19603:
 #0: ffff888023388250 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock_killable include/linux/mmap_lock.h:377 [inline]
 #0: ffff888023388250 (&mm->mmap_lock){++++}-{4:4}, at: __get_user_pages_locked mm/gup.c:1744 [inline]
 #0: ffff888023388250 (&mm->mmap_lock){++++}-{4:4}, at: faultin_page_range+0x3ef/0x8d0 mm/gup.c:1912
 #1: ffff8881404605f8 (sb_pagefaults#2){.+.+}-{0:0}, at: do_page_mkwrite+0x150/0x310 mm/memory.c:3489
1 lock held by syz-executor/20090:
 #0: ffffffff8e863af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #0: ffffffff8e863af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #0: ffffffff8e863af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8e9/0x1c80 net/core/rtnetlink.c:4064
1 lock held by syz-executor/20403:
 #0: ffffffff8e863af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #0: ffffffff8e863af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #0: ffffffff8e863af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8e9/0x1c80 net/core/rtnetlink.c:4064
2 locks held by syz-executor/20406:
 #0: ffffffff8dfed6e0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8dfed6e0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
 #0: ffffffff8dfed6e0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
 #1: ffffffff8e863af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #1: ffffffff8e863af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #1: ffffffff8e863af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8e9/0x1c80 net/core/rtnetlink.c:4064
1 lock held by syz-executor/20413:
 #0: ffffffff8e863af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #0: ffffffff8e863af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #0: ffffffff8e863af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8e9/0x1c80 net/core/rtnetlink.c:4064
1 lock held by syz.8.4299/20490:

=============================================

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 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:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
 watchdog+0xf60/0xfa0 kernel/hung_task.c:495
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 63 87 27 00 f3 0f 1e fa fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc900001d7de0 EFLAGS: 000002c2
RAX: 7148b3075b702800 RBX: ffffffff81953c47 RCX: 7148b3075b702800
RDX: 0000000000000001 RSI: ffffffff8cd8ed48 RDI: ffffffff8b3ddfe0
RBP: ffffc900001d7f10 R08: ffff8880b89334db R09: 1ffff1101712669b
R10: dffffc0000000000 R11: ffffed101712669c R12: ffffffff8ed64770
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110036deb40
FS:  0000000000000000(0000) GS:ffff888126ef4000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000a4030 CR3: 0000000083f0e000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:190 [inline]
 do_idle+0x1e7/0x510 kernel/sched/idle.c:330
 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315
 common_startup_64+0x13e/0x147
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/28 14:57 upstream e538109ac71d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in filemap_page_mkwrite
* Struck through repros no longer work on HEAD.