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BUG: soft lockup in kvm_vcpu_ioctl

Status: auto-obsoleted due to no activity on 2024/07/12 20:15
Reported-by: syzbot+7c9d5e8ef7a927a53a6c@syzkaller.appspotmail.com
First crash: 447d, last: 447d
▶ ▼ Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 BUG: soft lockup in kvm_vcpu_ioctl C error 2 1525d 1528d 0/1 upstream: reported C repro on 2021/04/28 21:34
upstream INFO: rcu detected stall in kvm_vcpu_ioctl (2) kvm 1 330d 330d 0/29 auto-obsoleted due to no activity on 2024/11/06 13:35
upstream INFO: rcu detected stall in kvm_vcpu_ioctl (3) kvm-x86 2 125d 191d 0/29 auto-obsoleted due to no activity on 2025/05/30 15:19
upstream INFO: rcu detected stall in kvm_vcpu_ioctl mm C error unreliable 251 1311d 2489d 0/29 closed as invalid on 2022/02/08 10:48
linux-4.19 INFO: rcu detected stall in kvm_vcpu_ioctl C error 46 1346d 2002d 0/1 upstream: reported C repro on 2020/01/10 19:56
linux-5.15 INFO: rcu detected stall in kvm_vcpu_ioctl 3 5d00h 29d 0/3 upstream: reported on 2025/06/05 19:21

Sample crash report:
watchdog: BUG: soft lockup - CPU#0 stuck for 246s! [syz-executor.3:25334]
Modules linked in:
CPU: 0 PID: 25334 Comm: syz-executor.3 Not tainted 5.15.148-syzkaller-00718-g993bed180178 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
RIP: 0010:kvm_wait+0x147/0x180 arch/x86/kernel/kvm.c:918
Code: 4c 89 e8 48 c1 e8 03 42 0f b6 04 20 84 c0 44 8b 74 24 1c 75 34 41 0f b6 45 00 44 38 f0 75 10 66 90 0f 00 2d 5b 03 f3 03 fb f4 <e9> 24 ff ff ff fb e9 1e ff ff ff 44 89 e9 80 e1 07 38 c1 7c a3 4c
RSP: 0018:ffffc90000af7320 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 1ffff9200015ee68 RCX: 1ffffffff0d1aa9c
RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff8881f7037ed4
RBP: ffffc90000af73d0 R08: dffffc0000000000 R09: ffffed103ee06fdb
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff8881f7037ed4 R14: 0000000000000001 R15: 1ffff9200015ee6c
FS:  00007f77a6c806c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2e023000 CR3: 00000001bb52e000 CR4: 00000000003526b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000003ef1 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 pv_wait arch/x86/include/asm/paravirt.h:597 [inline]
 pv_wait_node kernel/locking/qspinlock_paravirt.h:325 [inline]
 __pv_queued_spin_lock_slowpath+0x41b/0xc40 kernel/locking/qspinlock.c:473
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
 do_raw_spin_lock include/linux/spinlock.h:187 [inline]
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline]
 _raw_spin_lock_bh+0x139/0x1b0 kernel/locking/spinlock.c:178
 sock_hash_delete_elem+0xb1/0x2f0 net/core/sock_map.c:937
 bpf_prog_2c29ac5cdc6b1842+0x3a/0x7f0
 bpf_dispatcher_nop_func include/linux/bpf.h:785 [inline]
 __bpf_prog_run include/linux/filter.h:625 [inline]
 bpf_prog_run include/linux/filter.h:632 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1883 [inline]
 bpf_trace_run2+0xec/0x210 kernel/trace/bpf_trace.c:1920
 __bpf_trace_kfree+0x6f/0x90 include/trace/events/kmem.h:118
 trace_kfree include/trace/events/kmem.h:118 [inline]
 kfree+0x1f3/0x220 mm/slub.c:4569
 kvm_arch_vcpu_ioctl+0x1866/0x1c20 arch/x86/kvm/x86.c:5515
 kvm_vcpu_ioctl+0x6d6/0xcf0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:4049
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0x114/0x190 fs/ioctl.c:860
 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f77a7f0ce69
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f77a6c800c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f77a803af80 RCX: 00007f77a7f0ce69
RDX: 0000000020000380 RSI: 000000004068aea3 RDI: 0000000000000005
RBP: 00007f77a7f5947a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f77a803af80 R15: 00007ffc57309548
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 25246 Comm: udevd Not tainted 5.15.148-syzkaller-00718-g993bed180178 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
RIP: 0010:kvm_wait+0x147/0x180 arch/x86/kernel/kvm.c:918
Code: 4c 89 e8 48 c1 e8 03 42 0f b6 04 20 84 c0 44 8b 74 24 1c 75 34 41 0f b6 45 00 44 38 f0 75 10 66 90 0f 00 2d 5b 03 f3 03 fb f4 <e9> 24 ff ff ff fb e9 1e ff ff ff 44 89 e9 80 e1 07 38 c1 7c a3 4c
RSP: 0018:ffffc9000276f080 EFLAGS: 00000246
RAX: 0000000000000003 RBX: 1ffff920004ede14 RCX: ffffffff8154f88f
RDX: dffffc0000000000 RSI: 0000000000000003 RDI: ffff88812412e348
RBP: ffffc9000276f130 R08: dffffc0000000000 R09: ffffed1024825c6a
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff88812412e348 R14: 0000000000000003 R15: 1ffff920004ede18
FS:  00007fb5054f3c80(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555557030858 CR3: 0000000118fa6000 CR4: 00000000003526a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 pv_wait arch/x86/include/asm/paravirt.h:597 [inline]
 pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline]
 __pv_queued_spin_lock_slowpath+0x6bc/0xc40 kernel/locking/qspinlock.c:508
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
 do_raw_spin_lock include/linux/spinlock.h:187 [inline]
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline]
 _raw_spin_lock_bh+0x139/0x1b0 kernel/locking/spinlock.c:178
 sock_hash_delete_elem+0xb1/0x2f0 net/core/sock_map.c:937
 bpf_prog_2c29ac5cdc6b1842+0x3a/0x7f0
 bpf_dispatcher_nop_func include/linux/bpf.h:785 [inline]
 __bpf_prog_run include/linux/filter.h:625 [inline]
 bpf_prog_run include/linux/filter.h:632 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1883 [inline]
 bpf_trace_run2+0xec/0x210 kernel/trace/bpf_trace.c:1920
 __bpf_trace_kfree+0x6f/0x90 include/trace/events/kmem.h:118
 trace_kfree include/trace/events/kmem.h:118 [inline]
 kfree+0x1f3/0x220 mm/slub.c:4569
 sk_psock_free_link include/linux/skmsg.h:420 [inline]
 sock_map_del_link net/core/sock_map.c:160 [inline]
 sock_map_unref+0x352/0x4d0 net/core/sock_map.c:182
 sock_hash_delete_elem+0x274/0x2f0 net/core/sock_map.c:941
 bpf_prog_2c29ac5cdc6b1842+0x3a/0x7f0
 bpf_dispatcher_nop_func include/linux/bpf.h:785 [inline]
 __bpf_prog_run include/linux/filter.h:625 [inline]
 bpf_prog_run include/linux/filter.h:632 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1883 [inline]
 bpf_trace_run2+0xec/0x210 kernel/trace/bpf_trace.c:1920
 __bpf_trace_kfree+0x6f/0x90 include/trace/events/kmem.h:118
 trace_kfree include/trace/events/kmem.h:118 [inline]
 kfree+0x1f3/0x220 mm/slub.c:4569
 skb_free_head net/core/skbuff.c:656 [inline]
 skb_release_data+0x8a9/0xa80 net/core/skbuff.c:678
 skb_release_all net/core/skbuff.c:743 [inline]
 __kfree_skb net/core/skbuff.c:757 [inline]
 consume_skb+0xac/0x250 net/core/skbuff.c:930
 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
 netlink_unicast+0x8e7/0xac0 net/netlink/af_netlink.c:1356
 netlink_sendmsg+0xa0a/0xd20 net/netlink/af_netlink.c:1924
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2431
 ___sys_sendmsg+0x252/0x2e0 net/socket.c:2485
 __sys_sendmsg net/socket.c:2514 [inline]
 __do_sys_sendmsg net/socket.c:2523 [inline]
 __se_sys_sendmsg+0x19a/0x260 net/socket.c:2521
 __x64_sys_sendmsg+0x7b/0x90 net/socket.c:2521
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fb50562ca4b
Code: ff 89 ef 48 89 04 24 e8 22 56 f9 ff 48 8b 04 24 48 83 c4 20 5d c3 c3 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 6d 48 8b 15 ae c3 0c 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffda310aac8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00005584eceddb40 RCX: 00007fb50562ca4b
RDX: 0000000000000000 RSI: 00007ffda310aad8 RDI: 000000000000000c
RBP: 0000000000000000 R08: 0000000000000001 R09: 06a4ec5869918615
R10: 1999999999999999 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000000cf R14: 0000000000000000 R15: 00005584ecea82c0
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/13 20:09 android13-5.15-lts 993bed180178 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 BUG: soft lockup in kvm_vcpu_ioctl
* Struck through repros no longer work on HEAD.