INFO: task hung in kvm_mmu_uninit_tdp_mmu (2)

Status: premoderation: reported on 2026/01/24 19:57
Reported-by: syzbot+aebf766ff4e64a1b32c9@syzkaller.appspotmail.com
First crash: 214d, last: 3d18h
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-6-12 INFO: task hung in kvm_mmu_uninit_tdp_mmu 1 115 287d 432d 0/1 auto-obsoleted due to no activity on 2026/01/01 13:24

Sample crash report:
INFO: task syz.5.383:1720 blocked for more than 122 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.383       state:D stack:0     pid:1720  tgid:1718  ppid:973    flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6060 [inline]
 __schedule+0x1496/0x20b0 kernel/sched/core.c:7880
 __schedule_loop kernel/sched/core.c:7957 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7972
 schedule_timeout+0xc7/0x3b0 kernel/time/timer.c:2596
 do_wait_for_common kernel/sched/completion.c:95 [inline]
 __wait_for_common kernel/sched/completion.c:116 [inline]
 wait_for_common+0x368/0x650 kernel/sched/completion.c:127
 wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148
 rcu_barrier+0x45a/0x580 kernel/rcu/tree.c:4657
 kvm_mmu_uninit_tdp_mmu+0x1ea/0x210 arch/x86/kvm/mmu/tdp_mmu.c:51
 kvm_mmu_uninit_vm+0x27/0x60 arch/x86/kvm/mmu/mmu.c:6569
 kvm_arch_destroy_vm+0x395/0x410 arch/x86/kvm/x86.c:13008
 kvm_destroy_vm virt/kvm/kvm_main.c:1355 [inline]
 kvm_put_kvm+0xadf/0x12d0 virt/kvm/kvm_main.c:1392
 kvm_vm_release+0x47/0x70 virt/kvm/kvm_main.c:1415
 __fput+0x20b/0xa30 fs/file_table.c:447
 ____fput+0x20/0x30 fs/file_table.c:475
 task_work_run+0x1e8/0x260 kernel/task_work.c:246
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0xa46/0x2850 kernel/exit.c:955
 do_group_exit+0x21f/0x2f0 kernel/exit.c:1098
 get_signal+0x134c/0x1490 kernel/signal.c:2933
 arch_do_signal_or_restart+0xbc/0x700 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x57/0xb0 kernel/entry/common.c:218
 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f94c1f9e0d9
RSP: 002b:00007f94c2f060e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f94c2226098 RCX: 00007f94c1f9e0d9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f94c2226098
RBP: 00007f94c2226090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f94c2226128 R14: 00007fff640ef450 R15: 00007fff640ef538
 </TASK>
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 9a2c17613351c9eac8e18d74829f474689ac6bc1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 nmi_cpu_backtrace+0x2ba/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
 watchdog+0xe45/0xf90 kernel/hung_task.c:423
 kthread+0x2c7/0x360 kernel/kthread.c:389
 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 20 Comm: rcuop/0 Not tainted syzkaller #0 9a2c17613351c9eac8e18d74829f474689ac6bc1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:get_freepointer_safe mm/slub.c:-1 [inline]
RIP: 0010:__slab_alloc_node mm/slub.c:4080 [inline]
RIP: 0010:slab_alloc_node mm/slub.c:4239 [inline]
RIP: 0010:kmem_cache_alloc_noprof+0xe2/0x410 mm/slub.c:4260
Code: 80 7d cf 01 48 89 d8 75 21 ba 08 00 00 00 4c 89 7d 98 49 89 ff 4c 89 f7 48 89 de e8 a8 3f e5 ff 4c 89 ff 4c 8b 7d 98 4c 89 f0 <48> 0f cb 48 33 18 49 33 9f d8 00 00 00 49 8d 4d 08 49 8b 37 4c 89
RSP: 0018:ffffc900002305f0 EFLAGS: 00000297
RAX: ffff88813a613d00 RBX: ffff88813a613d00 RCX: 0000000000073580
RDX: dffffc0000000000 RSI: 0000000000000100 RDI: ffffc90000230627
RBP: ffffc90000230658 R08: ffff888103663900 R09: 0000000000000003
R10: 0000000000000002 R11: 0000000000000100 R12: ffff88813a613c80
R13: 00000000037b3929 R14: ffffc90000230618 R15: ffff888101a4b000
FS:  0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffda01febcc CR3: 00000001027d8000 CR4: 00000000003526b0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 skb_clone+0x21d/0x470 net/core/skbuff.c:2084
 deliver_clone net/bridge/br_forward.c:125 [inline]
 br_flood+0x650/0x720 net/bridge/br_forward.c:246
 br_handle_frame_finish+0x1157/0x1620 net/bridge/br_input.c:215
 nf_hook_bridge_pre net/bridge/br_input.c:301 [inline]
 br_handle_frame+0x5a5/0xba0 net/bridge/br_input.c:424
 __netif_receive_skb_core+0xfc1/0x3a70 net/core/dev.c:5695
 __netif_receive_skb_one_core net/core/dev.c:5799 [inline]
 __netif_receive_skb net/core/dev.c:5914 [inline]
 process_backlog+0x40b/0xaf0 net/core/dev.c:6250
 __napi_poll+0xcd/0x600 net/core/dev.c:6901
 napi_poll net/core/dev.c:6970 [inline]
 net_rx_action+0x5dc/0xd70 net/core/dev.c:7092
 handle_softirqs+0x1aa/0x620 kernel/softirq.c:621
 __do_softirq+0xf/0x16 kernel/softirq.c:659
 do_softirq+0xb8/0x110 kernel/softirq.c:503
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 rcu_do_batch+0x590/0xcb0 kernel/rcu/tree.c:2594
 nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline]
 rcu_nocb_cb_kthread+0x533/0xb60 kernel/rcu/tree_nocb.h:957
 kthread+0x2c7/0x360 kernel/kthread.c:389
 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
net_ratelimit: 121953 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:16:bd:10:1f:fc:10, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
net_ratelimit: 144527 callbacks suppressed
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:16:bd:10:1f:fc:10, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)

Crashes (140):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/23 16:35 android16-6.12 e8c85685a629 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/08/21 19:49 android16-6.12 3ab5872299d5 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/08/21 05:31 android16-6.12 11fb45c3d713 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/08/21 04:01 android16-6.12 11fb45c3d713 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/08/19 00:10 android16-6.12 8dc5b20ad3ea 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/08/17 11:19 android16-6.12 26014f6c6077 905244d6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/08/16 03:16 android16-6.12 26014f6c6077 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/08/14 07:27 android16-6.12 7c466513655f b13552fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/08/09 16:09 android16-6.12 309759bcbe6d 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/08/09 09:11 android16-6.12 309759bcbe6d 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/08/07 04:29 android16-6.12 749a6f9d41aa c38879ea .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/08/01 12:55 android16-6.12 1a138e24e292 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/08/01 08:22 android16-6.12 1a138e24e292 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/30 06:12 android16-6.12 f1c9c21d1c2f 6ef5c1e2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/28 20:45 android16-6.12 c56681255a47 edc8a875 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/28 06:30 android16-6.12 7b9e76cc9df5 45ae1df4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/26 01:00 android16-6.12 579215f16d4e 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/24 09:46 android16-6.12 629d76c0f948 544adce9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/24 04:43 android16-6.12 629d76c0f948 544adce9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/23 12:56 android16-6.12 6599be6df4d0 71a13572 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/22 00:27 android16-6.12 c2f8d5c68db2 b561ce9c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/21 21:13 android16-6.12 c2f8d5c68db2 7c5de9c3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/21 19:26 android16-6.12 c2f8d5c68db2 7c5de9c3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/19 09:48 android16-6.12 0fd55a309793 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/11 14:06 android16-6.12 0026e4ecedf0 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/07 20:29 android16-6.12 68c198f6d8bc 76cdc0c0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/07 11:03 android16-6.12 86a5aeeeecfe 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/07 06:53 android16-6.12 86a5aeeeecfe 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/07 05:04 android16-6.12 86a5aeeeecfe 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/06 09:00 android16-6.12 26ae30f2807e fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/04 09:33 android16-6.12 d36feda1de57 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/04 08:27 android16-6.12 d36feda1de57 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/04 05:01 android16-6.12 d36feda1de57 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/03 13:09 android16-6.12 d36feda1de57 58bf2096 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/07/03 06:43 android16-6.12 d36feda1de57 58bf2096 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/06/26 22:57 android16-6.12 220923cf9f76 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/06/26 07:58 android16-6.12 cc87569b5721 7ff32d8b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/06/24 06:54 android16-6.12 24621bda288e 042555ff .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/06/23 16:42 android16-6.12 8f68185b8289 4b1d8f01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/06/22 03:32 android16-6.12 8f68185b8289 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/06/20 08:39 android16-6.12 8f68185b8289 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/06/19 18:40 android16-6.12 8f68185b8289 570c59ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/06/18 17:14 android16-6.12 8f68185b8289 a776b0d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/06/18 15:08 android16-6.12 8f68185b8289 a776b0d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/06/17 17:06 android16-6.12 8f68185b8289 b62b3ded .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/06/17 05:18 android16-6.12 8f68185b8289 62cc6db3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/06/16 23:26 android16-6.12 8f68185b8289 62cc6db3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/06/15 05:33 android16-6.12 8f68185b8289 1d2f3589 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/06/10 10:33 android16-6.12 cf3d484a7cc5 34dab4be .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/06/07 17:39 android16-6.12 468e09dd6f52 cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/06/07 13:53 android16-6.12 468e09dd6f52 cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
2026/06/07 04:44 android16-6.12 468e09dd6f52 cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in kvm_mmu_uninit_tdp_mmu
* Struck through repros no longer work on HEAD.