INFO: task syz.8.3204:22933 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.3204 state:D stack:28504 pid:22933 tgid:22894 ppid:18447 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x1585/0x5340 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7004
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
blk_trace_startstop+0x8f/0x610 kernel/trace/blktrace.c:901
blk_trace_ioctl+0x315/0x740 kernel/trace/blktrace.c:947
blkdev_common_ioctl+0x13a7/0x3250 block/ioctl.c:724
blkdev_ioctl+0x528/0x740 block/ioctl.c:798
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2084d9bf79
RSP: 002b:00007f2082b91028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f2085016270 RCX: 00007f2084d9bf79
RDX: 0000000000000000 RSI: 0000000000001275 RDI: 0000000000000008
RBP: 00007f2084e327e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2085016308 R14: 00007f2085016270 R15: 00007fffcdd165a8
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
1 lock held by kswapd1/86:
1 lock held by udevd/5190:
2 locks held by getty/5577:
#0: ffff8880375010a0 (&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+0x45c/0x13c0 drivers/tty/n_tty.c:2211
1 lock held by udevd/20513:
4 locks held by syz.8.3204/22925:
1 lock held by syz.8.3204/22933:
#0: ffff8880262408e0 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_startstop+0x8f/0x610 kernel/trace/blktrace.c:901
3 locks held by udevd/25038:
#0: ffff88807b12f088 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310
#1: ffff8880b863ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb6/0x150 kernel/sched/core.c:655
#2: ffff8880b8624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
2 locks held by sed/25290:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xfd9/0x1030 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
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: 20607 Comm: udevd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:add_bits+0x25/0x9e0 lib/842/842_compress.c:-1
Code: 90 90 90 90 90 55 41 57 41 56 41 55 41 54 53 48 83 ec 48 89 d5 49 89 f7 49 89 fd 49 bc 00 00 00 00 00 fc ff df e8 db 20 0c fd <4d> 8d 75 28 49 8d 5d 18 4c 89 6c 24 08 49 8d 4d 20 4c 89 f0 48 c1
RSP: 0018:ffffc9000e4c5a18 EFLAGS: 00000293
RAX: ffffffff84b98185 RBX: 0000000000000001 RCX: ffff888026c1bc80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff88804c560000
RBP: 0000000000000005 R08: ffff888196efbd54 R09: ffff888196efbd53
R10: 1ffff11032ddf7aa R11: ffffed10098adc04 R12: dffffc0000000000
R13: ffff88804c560000 R14: ffff88804c560000 R15: 0000000000000001
FS: 00007f721fd51880(0000) GS:ffff888125560000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005606a45ef1c0 CR3: 0000000067370000 CR4: 00000000003526f0
Call Trace:
add_template lib/842/842_compress.c:233 [inline]
process_next lib/842/842_compress.c:460 [inline]
sw842_compress+0x1b57/0x4b50 lib/842/842_compress.c:545
scomp_acomp_comp_decomp+0x72d/0xa00 crypto/scompress.c:-1
crypto_acomp_compress+0x4b3/0xbe0 crypto/acompress.c:289
zswap_compress mm/zswap.c:885 [inline]
zswap_store_page mm/zswap.c:1416 [inline]
zswap_store+0xdce/0x1f80 mm/zswap.c:1527
swap_writeout+0x70c/0xd70 mm/page_io.c:275
writeout mm/vmscan.c:652 [inline]
pageout mm/vmscan.c:699 [inline]
shrink_folio_list+0x33fd/0x5290 mm/vmscan.c:1425
evict_folios+0x4795/0x5880 mm/vmscan.c:4717
try_to_shrink_lruvec+0xb62/0xfa0 mm/vmscan.c:4880
shrink_one+0x25c/0x710 mm/vmscan.c:4925
shrink_many mm/vmscan.c:4988 [inline]
lru_gen_shrink_node mm/vmscan.c:5066 [inline]
shrink_node+0x3197/0x3a90 mm/vmscan.c:6046
shrink_zones mm/vmscan.c:6299 [inline]
do_try_to_free_pages+0x6a2/0x1980 mm/vmscan.c:6361
try_to_free_pages+0x8f2/0xe90 mm/vmscan.c:6600
__perform_reclaim mm/page_alloc.c:4424 [inline]
__alloc_pages_direct_reclaim+0x148/0x310 mm/page_alloc.c:4446
__alloc_pages_slowpath+0x57d/0xd40 mm/page_alloc.c:4846
__alloc_frozen_pages_noprof+0x322/0x380 mm/page_alloc.c:5263
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2485
alloc_frozen_pages_noprof mm/mempolicy.c:2556 [inline]
alloc_pages_noprof+0xa8/0x190 mm/mempolicy.c:2576
folio_alloc_noprof+0x1e/0x30 mm/mempolicy.c:2586
filemap_alloc_folio_noprof+0x111/0x470 mm/filemap.c:1013
ractl_alloc_folio mm/readahead.c:189 [inline]
page_cache_ra_unbounded+0x39b/0xa50 mm/readahead.c:277
do_page_cache_ra mm/readahead.c:334 [inline]
page_cache_ra_order+0xaf2/0xeb0 mm/readahead.c:538
do_sync_mmap_readahead+0x6ad/0x8e0 mm/filemap.c:3405
filemap_fault+0x6e2/0x1320 mm/filemap.c:3554
__do_fault+0x138/0x390 mm/memory.c:5364
do_read_fault mm/memory.c:5799 [inline]
do_fault mm/memory.c:5933 [inline]
do_pte_missing+0x228f/0x3750 mm/memory.c:4477
handle_pte_fault mm/memory.c:6317 [inline]
__handle_mm_fault mm/memory.c:6455 [inline]
handle_mm_fault+0x1bec/0x3310 mm/memory.c:6624
do_user_addr_fault+0xa73/0x1340 arch/x86/mm/fault.c:1334
handle_page_fault arch/x86/mm/fault.c:1474 [inline]
exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f721f66beb0
Code: Unable to access opcode bytes at 0x7f721f66be86.
RSP: 002b:00007ffcbe098e28 EFLAGS: 00010246
RAX: 000056066d8de4c0 RBX: 00007ffcbe099250 RCX: 000000000a313036
RDX: 000000000000000a RSI: 0000000000000000 RDI: 00007ffcbe099252
RBP: 00005606a45fc690 R08: 00005606a463d93e R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 000056066d8ef5a0
R13: 00005606a45d2730 R14: 00007ffcbe098e50 R15: 000056066d901140