INFO: task syz.1.750:6712 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.750 state:D stack:24560 pid: 6712 ppid: 4188 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11c3/0x4350 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
rwsem_down_read_slowpath+0x53e/0x9b0 kernel/locking/rwsem.c:1055
__down_read_common kernel/locking/rwsem.c:1239 [inline]
__down_read kernel/locking/rwsem.c:1252 [inline]
down_read+0x96/0x2e0 kernel/locking/rwsem.c:1500
mmap_read_lock+0x1c/0x50 include/linux/mmap_lock.h:117
do_user_addr_fault+0xc3f/0xc90 arch/x86/mm/fault.c:1306
handle_page_fault arch/x86/mm/fault.c:1443 [inline]
exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1496
asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0033:0x7fd0b7fdd6e0
RSP: 002b:00007fd0b6215a78 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00007fd0b8245fa0 RCX: 00007fd0b7fbe159
RDX: 00007fd0b6215a80 RSI: 00007fd0b6215bb0 RDI: 0000000000000021
RBP: 00007fd0b805506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd0b8246038 R14: 00007fd0b8245fa0 R15: 00007fffd5607698
Showing all locks held in the system:
1 lock held by kthreadd/2:
#0:
ffffffff8c3ded80 (fs_reclaim
){+.+.}-{0:0}
, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
, at: __alloc_pages_slowpath+0x1017/0x2700 mm/page_alloc.c:5128
3 locks held by kworker/1:1/23:
1 lock held by khungtaskd/27:
#0:
ffffffff8c31ef60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kswapd1/256:
1 lock held by jbd2/sda1-8/3519:
#0: ffffffff8c3b0028 (oom_lock){+.+.}-{3:3}, at: __alloc_pages_may_oom mm/page_alloc.c:4308 [inline]
#0: ffffffff8c3b0028 (oom_lock){+.+.}-{3:3}, at: __alloc_pages_slowpath+0x1bad/0x2700 mm/page_alloc.c:5177
2 locks held by klogd/3546:
#0:
ffff88807e62a428
(
&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2bb/0xc90 arch/x86/mm/fault.c:1296
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath+0x1017/0x2700 mm/page_alloc.c:5128
2 locks held by udevd/3557:
#0: ffff88807e62ea28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#0: ffff88807e62ea28 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2bb/0xc90 arch/x86/mm/fault.c:1296
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath+0x1017/0x2700 mm/page_alloc.c:5128
2 locks held by dhcpcd/3849:
#0: ffff88802c477128 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#0: ffff88802c477128 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2bb/0xc90 arch/x86/mm/fault.c:1296
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath+0x1017/0x2700 mm/page_alloc.c:5128
2 locks held by crond/3924:
#0: ffff88802bca4e28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#0: ffff88802bca4e28 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2bb/0xc90 arch/x86/mm/fault.c:1296
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath+0x1017/0x2700 mm/page_alloc.c:5128
2 locks held by getty/3941:
#0: ffff88814cad3098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002d032e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x594/0x1a50 drivers/tty/n_tty.c:2158
1 lock held by syz-executor/4172:
#0: ffff88807a296a28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#0: ffff88807a296a28 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2bb/0xc90 arch/x86/mm/fault.c:1296
2 locks held by syz-executor/4186:
#0: ffff88802cfba428 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#0: ffff88802cfba428 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2bb/0xc90 arch/x86/mm/fault.c:1296
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath+0x1017/0x2700 mm/page_alloc.c:5128
2 locks held by syz-executor/4188:
#0: ffff88802cfb9d28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#0: ffff88802cfb9d28 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2bb/0xc90 arch/x86/mm/fault.c:1296
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath+0x1017/0x2700 mm/page_alloc.c:5128
2 locks held by syz.5.654/6411:
#0: ffff8880465c6120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1744 [inline]
#0: ffff8880465c6120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_setsockopt+0x7f3/0x1af0 net/packet/af_packet.c:3860
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath+0x1017/0x2700 mm/page_alloc.c:5128
1 lock held by syz.1.750/6711:
#0: ffff888077976328 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#0: ffff888077976328 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x16c/0x2d0 mm/util.c:549
1 lock held by syz.1.750/6712:
#0: ffff888077976328 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock+0x1c/0x50 include/linux/mmap_lock.h:117
4 locks held by syz.1.750/6718:
#0: ffff888077976328 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:117 [inline]
#0: ffff888077976328 (&mm->mmap_lock){++++}-{3:3}, at: __mm_populate+0x164/0x3b0 mm/gup.c:1618
#1: ffff8881415d1970 (&hugetlbfs_i_mmap_rwsem_key){++++}-{3:3}, at: i_mmap_lock_read include/linux/fs.h:523 [inline]
#1: ffff8881415d1970 (&hugetlbfs_i_mmap_rwsem_key){++++}-{3:3}, at: hugetlb_fault+0x424/0x2830 mm/hugetlb.c:5119
#2: ffff8880195d20f8 (&hugetlb_fault_mutex_table[i]){+.+.}-{3:3}, at: hugetlb_fault+0x62c/0x2830 mm/hugetlb.c:5133
#3: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
#3: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
#3: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath+0x1017/0x2700 mm/page_alloc.c:5128
2 locks held by syz-executor/6723:
#0: ffff88807e0cf828 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock+0x1c/0x50 include/linux/mmap_lock.h:117
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
#1: ffffffff8c3ded80 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath+0x1017/0x2700 mm/page_alloc.c:5128
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe1b/0xe60 kernel/hung_task.c:369
kthread+0x42e/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 255 Comm: kswapd0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:132 [inline]
RIP: 0010:lock_acquire+0x1ca/0x400 kernel/locking/lockdep.c:5628
Code: c4 20 48 c7 c7 80 3e 2b 8a e8 02 58 64 08 b8 ff ff ff ff 65 0f c1 05 25 8b a5 7e 83 f8 01 0f 85 04 01 00 00 43 c6 44 3d 04 00 <48> c7 84 24 80 00 00 00 00 00 00 00 9c 8f 84 24 80 00 00 00 f7 84
RSP: 0000:ffffc900020674e0 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 93cdf67c7cdc6b00
RDX: 0000000000000000 RSI: ffffffff8a2b3e80 RDI: ffffffff8a7a48c0
RBP: ffffc90002067600 R08: dffffc0000000000 R09: 1ffffffff203e218
R10: dffffc0000000000 R11: fffffbfff203e219 R12: ffffffff8c31ef60
R13: 1ffff9200040cea8 R14: 0000000000000246 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f02d4a4bae8 CR3: 000000007e64e000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313
rcu_read_lock include/linux/rcupdate.h:740 [inline]
list_lru_count_one+0x49/0x310 mm/list_lru.c:181
list_lru_shrink_count include/linux/list_lru.h:123 [inline]
nfs4_xattr_entry_count+0x76/0x120 fs/nfs/nfs42xattr.c:978
do_shrink_slab+0x8d/0xd40 mm/vmscan.c:712
shrink_slab_memcg mm/vmscan.c:834 [inline]
shrink_slab+0x43d/0x7a0 mm/vmscan.c:913
shrink_node_memcgs mm/vmscan.c:2958 [inline]
shrink_node+0x11f5/0x2790 mm/vmscan.c:3079
kswapd_shrink_node mm/vmscan.c:3821 [inline]
balance_pgdat+0xdf3/0x1a10 mm/vmscan.c:4012
kswapd+0x7db/0xde0 mm/vmscan.c:4271
kthread+0x42e/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287