rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=62681, q=337 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4295065221-4295054719), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g62681 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:26728 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5380 [inline]
 __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
 schedule+0xbd/0x170 kernel/sched/core.c:6773
 schedule_timeout+0x160/0x280 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667
 rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1866
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 14863 Comm: syz.0.2223 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4774 [inline]
RIP: 0010:__lock_acquire+0x5fb/0x7c80 kernel/locking/lockdep.c:5087
Code: c0 0f 85 1b 63 00 00 44 0f b6 33 48 8b 44 24 48 0f b6 04 10 84 c0 0f 85 2a 63 00 00 41 8b 07 89 c3 81 e3 ff 1f 00 00 c1 e8 03 <25> f8 03 00 00 48 8d b8 00 75 da 90 be 08 00 00 00 e8 5f e6 75 00
RSP: 0018:ffffc90000007900 EFLAGS: 00000007
RAX: 000000000001880c RBX: 0000000000000067 RCX: ffffffff8166fe80
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffffffff90da7508
RBP: ffffc90000007b48 R08: ffffffff90da750f R09: 1ffffffff21b4ea1
R10: dffffc0000000000 R11: fffffbfff21b4ea2 R12: ffff888027d08ac4
R13: ffff888027d08000 R14: 0000000000000002 R15: ffff888027d08b00
FS:  00007f6432bf06c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2aef48 CR3: 0000000022468000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
 _raw_spin_lock_irq+0xa3/0xe0 kernel/locking/spinlock.c:170
 __run_hrtimer kernel/time/hrtimer.c:1754 [inline]
 __hrtimer_run_queues+0x5e3/0xc40 kernel/time/hrtimer.c:1814
 hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1876
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline]
 __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__kasan_check_write+0xa/0x20 mm/kasan/shadow.c:37
Code: f3 0f 1e fa 89 f6 48 8b 0c 24 31 d2 e9 df ea ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 f3 0f 1e fa 89 f6 48 8b 0c 24 <ba> 01 00 00 00 e9 bc ea ff ff 66 2e 0f 1f 84 00 00 00 00 00 66 90
RSP: 0018:ffffc9000be37a50 EFLAGS: 00000283
RAX: ffffffff841ef42d RBX: 0000000000000038 RCX: ffffffff841ef43a
RDX: ffffc9000ea60000 RSI: 0000000000000038 RDI: ffffc9000be37ae0
RBP: ffffc9000be37c70 R08: ffffffff8e4a856f R09: 1ffffffff1c950ad
R10: dffffc0000000000 R11: fffffbfff1c950ae R12: 000020000002bd78
R13: dffffc0000000000 R14: ffffc9000be37ae0 R15: 000020000002bd40
 instrument_copy_from_user_before include/linux/instrumented.h:129 [inline]
 _copy_from_user+0x7a/0xe0 lib/usercopy.c:22
 copy_from_user include/linux/uaccess.h:183 [inline]
 copy_msghdr_from_user net/socket.c:2525 [inline]
 recvmsg_copy_msghdr net/socket.c:2780 [inline]
 ___sys_recvmsg+0x12f/0x510 net/socket.c:2852
 do_recvmmsg+0x360/0x7d0 net/socket.c:2950
 __sys_recvmmsg net/socket.c:3029 [inline]
 __do_sys_recvmmsg net/socket.c:3052 [inline]
 __se_sys_recvmmsg net/socket.c:3045 [inline]
 __x64_sys_recvmmsg+0x191/0x240 net/socket.c:3045
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f6431d8efc9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6432bf0038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f6431fe6090 RCX: 00007f6431d8efc9
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f6431e11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6431fe6128 R14: 00007f6431fe6090 R15: 00007ffe680fb388
 </TASK>
watchdog: BUG: soft lockup - CPU#1 stuck for 246s! [khugepaged:35]
Modules linked in:
irq event stamp: 539242
hardirqs last  enabled at (539241): [<ffffffff8a80144a>] asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
hardirqs last disabled at (539242): [<ffffffff8a6e702e>] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1088
softirqs last  enabled at (539240): [<ffffffff81519e87>] __do_softirq kernel/softirq.c:612 [inline]
softirqs last  enabled at (539240): [<ffffffff81519e87>] invoke_softirq kernel/softirq.c:452 [inline]
softirqs last  enabled at (539240): [<ffffffff81519e87>] __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
softirqs last disabled at (539235): [<ffffffff81519e87>] __do_softirq kernel/softirq.c:612 [inline]
softirqs last disabled at (539235): [<ffffffff81519e87>] invoke_softirq kernel/softirq.c:452 [inline]
softirqs last disabled at (539235): [<ffffffff81519e87>] __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
CPU: 1 PID: 35 Comm: khugepaged Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline]
RIP: 0010:smp_call_function_many_cond+0xddf/0x1130 kernel/smp.c:855
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 da d6 0a 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 15 d3 0a 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 f9 d2
RSP: 0018:ffffc90000abf760 EFLAGS: 00000293
RAX: ffffffff817ab7d7 RBX: 1ffff110171c8791 RCX: ffff8880182e3c00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000abf8d0 R08: ffffffff8e4a856f R09: 1ffffffff1c950ad
R10: dffffc0000000000 R11: fffffbfff1c950ae R12: ffff8880b8e43c88
R13: dffffc0000000000 R14: ffff8880b8f3d348 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000627ae000 CR4: 00000000003526e0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 smp_call_function_many kernel/smp.c:878 [inline]
 smp_call_function+0x45/0x80 kernel/smp.c:900
 collapse_huge_page mm/khugepaged.c:1161 [inline]
 hpage_collapse_scan_pmd+0x271c/0x3f60 mm/khugepaged.c:1393
 khugepaged_scan_mm_slot mm/khugepaged.c:2411 [inline]
 khugepaged_do_scan mm/khugepaged.c:2499 [inline]
 khugepaged+0x8ef/0x1520 mm/khugepaged.c:2555
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 14863 Comm: syz.0.2223 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:do_raw_spin_unlock+0x0/0x230 kernel/locking/spinlock_debug.c:138
Code: ff e8 54 30 06 09 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c 6f ff ff ff e8 9f 9c 74 00 e9 65 ff ff ff 66 2e 0f 1f 84 00 00 00 00 00 <66> 0f 1f 00 55 41 57 41 56 41 55 41 54 53 48 89 fb 49 bc 00 00 00
RSP: 0018:ffffc90000007c78 EFLAGS: 00000046
RAX: 2f0d64788c430400 RBX: 0000000000000806 RCX: 2f0d64788c430400
RDX: 0000000000000001 RSI: ffffffff8aaace60 RDI: ffffffff97125930
RBP: ffffc90000007d08 R08: ffffffff8e4a856f R09: 1ffffffff1c950ad
R10: dffffc0000000000 R11: fffffbfff1c950ae R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffffff97125930 R15: 1ffff92000000f90
FS:  00007f6432bf06c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2aef48 CR3: 0000000022468000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:150 [inline]
 _raw_spin_unlock_irqrestore+0x79/0x110 kernel/locking/spinlock.c:194
 debug_hrtimer_deactivate kernel/time/hrtimer.c:455 [inline]
 debug_deactivate+0x1d/0x1d0 kernel/time/hrtimer.c:511
 __run_hrtimer kernel/time/hrtimer.c:1718 [inline]
 __hrtimer_run_queues+0x2bf/0xc40 kernel/time/hrtimer.c:1814
 hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1876
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline]
 __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__kasan_check_write+0xa/0x20 mm/kasan/shadow.c:37
Code: f3 0f 1e fa 89 f6 48 8b 0c 24 31 d2 e9 df ea ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 f3 0f 1e fa 89 f6 48 8b 0c 24 <ba> 01 00 00 00 e9 bc ea ff ff 66 2e 0f 1f 84 00 00 00 00 00 66 90
RSP: 0018:ffffc9000be37a50 EFLAGS: 00000283
RAX: ffffffff841ef42d RBX: 0000000000000038 RCX: ffffffff841ef43a
RDX: ffffc9000ea60000 RSI: 0000000000000038 RDI: ffffc9000be37ae0
RBP: ffffc9000be37c70 R08: ffffffff8e4a856f R09: 1ffffffff1c950ad
R10: dffffc0000000000 R11: fffffbfff1c950ae R12: 000020000002bd78
R13: dffffc0000000000 R14: ffffc9000be37ae0 R15: 000020000002bd40
 instrument_copy_from_user_before include/linux/instrumented.h:129 [inline]
 _copy_from_user+0x7a/0xe0 lib/usercopy.c:22
 copy_from_user include/linux/uaccess.h:183 [inline]
 copy_msghdr_from_user net/socket.c:2525 [inline]
 recvmsg_copy_msghdr net/socket.c:2780 [inline]
 ___sys_recvmsg+0x12f/0x510 net/socket.c:2852
 do_recvmmsg+0x360/0x7d0 net/socket.c:2950
 __sys_recvmmsg net/socket.c:3029 [inline]
 __do_sys_recvmmsg net/socket.c:3052 [inline]
 __se_sys_recvmmsg net/socket.c:3045 [inline]
 __x64_sys_recvmmsg+0x191/0x240 net/socket.c:3045
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f6431d8efc9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6432bf0038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f6431fe6090 RCX: 00007f6431d8efc9
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f6431e11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6431fe6128 R14: 00007f6431fe6090 R15: 00007ffe680fb388
 </TASK>