INFO: task syz.6.6305:32670 blocked for more than 143 seconds.
Tainted: G U W L XTNJ syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.6305 state:D stack:27464 pid:32670 tgid:32669 ppid:31567 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x60e0 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0xdd/0x390 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+0xc9a/0x1b90 kernel/locking/mutex.c:776
nfsd_nl_version_set_doit+0xc4/0x7a0 fs/nfsd/nfsctl.c:1743
genl_family_rcv_msg_doit+0x214/0x300 net/netlink/genetlink.c:1115
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0x560/0x800 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2550
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa54/0xc30 net/socket.c:2592
___sys_sendmsg+0x190/0x1e0 net/socket.c:2646
__sys_sendmsg+0x170/0x220 net/socket.c:2678
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5ebb39bf79
RSP: 002b:00007f5eb95f6028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f5ebb615fa0 RCX: 00007f5ebb39bf79
RDX: 0000000000000844 RSI: 00002000000004c0 RDI: 0000000000000004
RBP: 00007f5ebb4327e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5ebb616038 R14: 00007f5ebb615fa0 R15: 00007fff0934bc28
INFO: task syz.5.6318:32706 blocked for more than 143 seconds.
Tainted: G U W L XTNJ syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.6318 state:D stack:27464 pid:32706 tgid:32705 ppid:26649 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x60e0 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0xdd/0x390 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+0xc9a/0x1b90 kernel/locking/mutex.c:776
nfsd_nl_version_set_doit+0xc4/0x7a0 fs/nfsd/nfsctl.c:1743
genl_family_rcv_msg_doit+0x214/0x300 net/netlink/genetlink.c:1115
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0x560/0x800 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2550
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa54/0xc30 net/socket.c:2592
___sys_sendmsg+0x190/0x1e0 net/socket.c:2646
__sys_sendmsg+0x170/0x220 net/socket.c:2678
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efc90f9bf79
RSP: 002b:00007efc8f1f6028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007efc91215fa0 RCX: 00007efc90f9bf79
RDX: 0000000000000844 RSI: 00002000000004c0 RDI: 0000000000000004
RBP: 00007efc910327e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007efc91216038 R14: 00007efc91215fa0 R15: 00007ffd495a7f48
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e7e92e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e7e92e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e7e92e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by syz-executor/5812:
1 lock held by syz.1.4604/24818:
2 locks held by syz.0.6298/32637:
#0: ffffffff906bb430 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8ec55d88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1b20 fs/nfsd/nfsctl.c:1893
2 locks held by syz.6.6305/32670:
#0: ffffffff906bb430 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8ec55d88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_set_doit+0xc4/0x7a0 fs/nfsd/nfsctl.c:1743
2 locks held by syz.5.6318/32706:
#0: ffffffff906bb430 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8ec55d88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_set_doit+0xc4/0x7a0 fs/nfsd/nfsctl.c:1743
2 locks held by syz-executor/408:
#0: ffff88808751e0e0 (&type->s_umount_key#60){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88808751e0e0 (&type->s_umount_key#60){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88808751e0e0 (&type->s_umount_key#60){+.+.}-{4:4}, at: deactivate_super fs/super.c:508 [inline]
#0: ffff88808751e0e0 (&type->s_umount_key#60){+.+.}-{4:4}, at: deactivate_super+0xdf/0x110 fs/super.c:505
#1: ffffffff8ec55d88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:575
2 locks held by syz.3.6624/1714:
#0: ffff88802cbaa0e0 (&type->s_umount_key#60){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88802cbaa0e0 (&type->s_umount_key#60){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88802cbaa0e0 (&type->s_umount_key#60){+.+.}-{4:4}, at: deactivate_super fs/super.c:508 [inline]
#0: ffff88802cbaa0e0 (&type->s_umount_key#60){+.+.}-{4:4}, at: deactivate_super+0xdf/0x110 fs/super.c:505
#1: ffffffff8ec55d88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:575
2 locks held by syz-executor/2374:
4 locks held by syz.7.6762/2387:
1 lock held by syz.7.6762/2395:
10 locks held by syz.8.6770/2401:
#0: ffff88806dbe87f8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1255
#1: ffff888035f38420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:740
#2: ffff88803bd7d088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343
#3: ffff8880212bde18 (kn->active#215){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#3: ffff8880212bde18 (kn->active#215){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x332/0x5f0 fs/kernfs/file.c:344
#4: ffffffff8e7d58a0 (console_lock){+.+.}-{0:0}, at: rotate_all_store+0x22/0x400 drivers/video/fbdev/core/fbcon.c:3222
#5: ffff888026750a80 (&helper->lock){+.+.}-{4:4}, at: drm_fb_helper_pan_display+0xd6/0xa40 drivers/gpu/drm/drm_fb_helper.c:1260
#6: ffff888026840130 (&dev->master_mutex){+.+.}-{4:4}, at: drm_master_internal_acquire+0x21/0x80 drivers/gpu/drm/drm_auth.c:435
#7: ffff888026750898 (&client->modeset_mutex){+.+.}-{4:4}, at: drm_client_modeset_commit_locked+0x4c/0x580 drivers/gpu/drm/drm_client_modeset.c:1204
#8: ffffc9000d0ef910 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_client_modeset_commit_atomic+0xc4/0x7e0 drivers/gpu/drm/drm_client_modeset.c:1042
#9: ffffc9000d0ef6c8 (crtc_ww_class_mutex){+.+.}-{4:4}, at: drm_client_modeset_commit_atomic+0xc4/0x7e0 drivers/gpu/drm/drm_client_modeset.c:1042
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Tainted: G U W L XTNJ syzkaller #0 PREEMPT(full)
Tainted: [U]=USER, [W]=WARN, [L]=SOFTLOCKUP, [X]=AUX, [T]=RANDSTRUCT, [N]=TEST, [J]=FWCTL
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x1d7/0x230 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+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xd25/0x1050 kernel/hung_task.c:515
kthread+0x370/0x450 kernel/kthread.c:467
ret_from_fork+0x754/0xd80 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: 2387 Comm: syz.7.6762 Tainted: G U W L XTNJ syzkaller #0 PREEMPT(full)
Tainted: [U]=USER, [W]=WARN, [L]=SOFTLOCKUP, [X]=AUX, [T]=RANDSTRUCT, [N]=TEST, [J]=FWCTL
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:hlist_unhashed include/linux/list.h:962 [inline]
RIP: 0010:hlist_del_init include/linux/list.h:1019 [inline]
RIP: 0010:hash_del include/linux/hashtable.h:107 [inline]
RIP: 0010:update_hashtables lib/842/842_compress.c:434 [inline]
RIP: 0010:sw842_compress+0xf33/0x4450 lib/842/842_compress.c:552
Code: 89 f8 48 c1 e8 03 42 80 3c 30 00 0f 85 3a 33 00 00 48 8b 04 24 4c 89 6d 08 48 8d 58 01 48 81 fb 01 01 00 00 0f 83 0d 33 00 00 <48> 8d 2c 1b 48 8d 54 1d 00 49 8d bc d7 70 d0 00 00 48 89 fa 48 c1
RSP: 0018:ffffc9000678e440 EFLAGS: 00000283
RAX: 0000000000000054 RBX: 0000000000000055 RCX: 00000000000007e0
RDX: ffff888027733c80 RSI: ffffffff84fb003e RDI: ffff88805c0bd850
RBP: ffff88805c0bd848 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000012 R11: ffff88805c0b0042 R12: ffff88805c0bd830
R13: ffff88805c0b6068 R14: dffffc0000000000 R15: ffff88805c0b0000
FS: 00007ff0b53be6c0(0000) GS:ffff88812445a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff0b537c0e8 CR3: 00000000385ee000 CR4: 00000000003526f0
Call Trace:
crypto_scomp_decompress include/crypto/internal/scompress.h:79 [inline]
scomp_acomp_comp_decomp+0x732/0xc40 crypto/scompress.c:254
crypto_acomp_compress+0x14c/0x520 crypto/acompress.c:289
zswap_compress mm/zswap.c:885 [inline]
zswap_store_page mm/zswap.c:1416 [inline]
zswap_store+0xeda/0x29d0 mm/zswap.c:1527
swap_writeout+0x49d/0x12b0 mm/page_io.c:275
writeout mm/vmscan.c:650 [inline]
pageout mm/vmscan.c:697 [inline]
shrink_folio_list+0x54b6/0x6060 mm/vmscan.c:1416
shrink_inactive_list mm/vmscan.c:2014 [inline]
shrink_list mm/vmscan.c:2251 [inline]
shrink_lruvec+0xf5a/0x2c20 mm/vmscan.c:5808
shrink_node_memcgs mm/vmscan.c:6010 [inline]
shrink_node+0x8e1/0x3ee0 mm/vmscan.c:6051
shrink_zones mm/vmscan.c:6290 [inline]
do_try_to_free_pages+0x340/0x1870 mm/vmscan.c:6352
try_to_free_mem_cgroup_pages+0x2b2/0x820 mm/vmscan.c:6673
try_charge_memcg+0x3e3/0xc90 mm/memcontrol.c:2414
try_charge mm/memcontrol.c:2556 [inline]
charge_memcg+0xa6/0x280 mm/memcontrol.c:4745
__mem_cgroup_charge+0x2b/0x1e0 mm/memcontrol.c:4762
mem_cgroup_charge include/linux/memcontrol.h:665 [inline]
alloc_charge_folio+0x1d3/0x900 mm/khugepaged.c:1066
collapse_file+0x1c6/0x3cc0 mm/khugepaged.c:1865
hpage_collapse_scan_file+0x603/0x1fc0 mm/khugepaged.c:2380
madvise_collapse+0x412/0xbe0 mm/khugepaged.c:2809
madvise_vma_behavior+0x172d/0x2ec0 mm/madvise.c:1370
madvise_walk_vmas+0x2fe/0xa90 mm/madvise.c:1719
madvise_do_behavior+0x1ea/0x510 mm/madvise.c:1935
do_madvise+0x195/0x240 mm/madvise.c:2028
__do_sys_madvise mm/madvise.c:2037 [inline]
__se_sys_madvise mm/madvise.c:2035 [inline]
__x64_sys_madvise+0xa9/0x110 mm/madvise.c:2035
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff0b459bf79
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff0b53be028 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
RAX: ffffffffffffffda RBX: 00007ff0b4815fa0 RCX: 00007ff0b459bf79
RDX: 0000000000000019 RSI: ffffffffffff0005 RDI: 0000000000000000
RBP: 00007ff0b46327e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff0b4816038 R14: 00007ff0b4815fa0 R15: 00007ffff087d5f8