INFO: task syz.0.16:6761 blocked for more than 143 seconds.
Not tainted 6.15.0-syzkaller-11796-g5abc7438f1e9 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.16 state:D stack:23544 pid:6761 tgid:6760 ppid:6690 task_flags:0x400040 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935
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
inode_lock_shared include/linux/fs.h:882 [inline]
blkdev_write_iter+0x50b/0x710 block/fops.c:778
iter_file_splice_write+0x93a/0x1000 fs/splice.c:738
do_splice_from fs/splice.c:935 [inline]
direct_splice_actor+0x101/0x160 fs/splice.c:1158
splice_direct_to_actor+0x5a5/0xcc0 fs/splice.c:1102
do_splice_direct_actor fs/splice.c:1201 [inline]
do_splice_direct+0x181/0x270 fs/splice.c:1227
do_sendfile+0x4da/0x7e0 fs/read_write.c:1370
__do_sys_sendfile64 fs/read_write.c:1431 [inline]
__se_sys_sendfile64+0x13e/0x190 fs/read_write.c:1417
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd51218e169
RSP: 002b:00007fd512f78038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007fd5123b5fa0 RCX: 00007fd51218e169
RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000003
RBP: 00007fd512210a68 R08: 0000000000000000 R09: 0000000000000000
R10: 000400000000003f R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fd5123b5fa0 R15: 00007ffcb3f0eac8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5599:
#0: ffff888030c5c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by syz.0.16/6761:
#0: ffff888148c11320 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:882 [inline]
#0: ffff888148c11320 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_write_iter+0x50b/0x710 block/fops.c:778
3 locks held by syz.0.16/6763:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-syzkaller-11796-g5abc7438f1e9 #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:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
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: 13776 Comm: syz.1.3195 Not tainted 6.15.0-syzkaller-11796-g5abc7438f1e9 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:194 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x37/0x70 kernel/kcov.c:217
Code: 08 40 9c 92 65 8b 15 a8 e3 db 10 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 3c 16 00 00 00 74 2c 8b 91 18 16 00 00 <83> fa 02 75 21 48 8b 91 20 16 00 00 48 8b 32 48 8d 7e 01 8b 89 1c
RSP: 0018:ffffc9000d197310 EFLAGS: 00000246
RAX: ffffffff822f08c5 RBX: 0000000080000001 RCX: ffff88802ad5bc00
RDX: 0000000000000000 RSI: 0000000080000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff822f05aa
R10: dffffc0000000000 R11: fffff940002edbf1 R12: dffffc0000000000
R13: 0000000000000008 R14: 0000000000000001 R15: ffff88813fffa560
FS: 0000000000000000(0000) GS:ffff888125c5c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4d821dcf98 CR3: 000000000df38000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
rcu_read_unlock_sched include/linux/rcupdate.h:955 [inline]
pfn_valid+0x3d5/0x490 include/linux/mmzone.h:2168
page_table_check_clear+0x21/0x700 mm/page_table_check.c:70
ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline]
clear_full_ptes include/linux/pgtable.h:751 [inline]
zap_present_folio_ptes mm/memory.c:1518 [inline]
zap_present_ptes mm/memory.c:1590 [inline]
do_zap_pte_range mm/memory.c:1691 [inline]
zap_pte_range mm/memory.c:1735 [inline]
zap_pmd_range mm/memory.c:1827 [inline]
zap_pud_range mm/memory.c:1856 [inline]
zap_p4d_range mm/memory.c:1877 [inline]
unmap_page_range+0x326e/0x41c0 mm/memory.c:1898
unmap_single_vma mm/memory.c:1941 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:1985
exit_mmap+0x248/0xb50 mm/mmap.c:1284
__mmput+0x118/0x420 kernel/fork.c:1121
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x640/0x22e0 kernel/exit.c:943
do_group_exit+0x21c/0x2d0 kernel/exit.c:1104
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4d82f8e169
Code: Unable to access opcode bytes at 0x7f4d82f8e13f.
RSP: 002b:00007f4d821dd0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f4d831b6088 RCX: 00007f4d82f8e169
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f4d831b6088
RBP: 00007f4d831b6080 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4d831b608c
R13: 0000000000000000 R14: 00007ffeda9c93b0 R15: 00007ffeda9c9498