rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7813/2:b..l (detected by 0, t=10506 jiffies, g=31025, q=18 ncpus=2) task:syz.3.1070 state:R running task stack:24952 pid:7813 ppid:4255 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5243 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6560 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6872 irqentry_exit+0x53/0x80 kernel/entry/common.c:439 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:696 RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666 Code: 2b 00 74 08 4c 89 f7 e8 9f 49 77 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc90003ee7440 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920007dce94 RCX: 1ffff920007dce34 RDX: dffffc0000000000 RSI: ffffffff8b0c2ec0 RDI: ffffffff8b5f6d80 RBP: ffffc90003ee7590 R08: dffffc0000000000 R09: fffffbfff2256c4d R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920007dce90 R13: dffffc0000000000 R14: ffffc90003ee74a0 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] percpu_ref_tryget_many include/linux/percpu-refcount.h:241 [inline] percpu_ref_tryget+0x31/0x170 include/linux/percpu-refcount.h:266 obj_cgroup_tryget include/linux/memcontrol.h:779 [inline] __get_obj_cgroup_from_memcg+0x70/0xe0 mm/memcontrol.c:3001 get_obj_cgroup_from_current+0x170/0x280 mm/memcontrol.c:3021 memcg_slab_pre_alloc_hook mm/slab.h:485 [inline] slab_pre_alloc_hook+0x90/0x300 mm/slab.h:715 slab_alloc_node mm/slub.c:3318 [inline] __kmem_cache_alloc_node+0x47/0x260 mm/slub.c:3437 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc_node_track_caller+0xa0/0x220 mm/slab_common.c:956 kmemdup+0x26/0x60 mm/util.c:129 _Z7kmemdupPKvU17pass_object_size0mj include/linux/fortify-string.h:585 [inline] scm_fp_dup+0x54/0x2b0 net/core/scm.c:365 unix_peek_fds net/unix/af_unix.c:1731 [inline] __unix_dgram_recvmsg+0xb77/0x12c0 net/unix/af_unix.c:2500 ____sys_recvmsg+0x285/0x530 ___sys_recvmsg net/socket.c:2780 [inline] do_recvmmsg+0x46d/0xad0 net/socket.c:2874 __sys_recvmmsg net/socket.c:2953 [inline] __do_sys_recvmmsg net/socket.c:2976 [inline] __se_sys_recvmmsg net/socket.c:2969 [inline] __x64_sys_recvmmsg+0x195/0x240 net/socket.c:2969 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f5d28b8d169 RSP: 002b:00007f5d299dc038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f5d28da5fa0 RCX: 00007f5d28b8d169 RDX: 0000000000001800 RSI: 0000400000001dc0 RDI: 0000000000000005 RBP: 00007f5d28c0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000002002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f5d28da5fa0 R15: 00007ffd73eee238 rcu: rcu_preempt kthread starved for 10502 jiffies! g31025 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 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:25592 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5243 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6560 schedule+0xbf/0x180 kernel/sched/core.c:6636 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 7838 Comm: syz.0.1077 Not tainted 6.1.129-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:kasan_check_range+0x1/0x290 mm/kasan/generic.c:188 Code: 01 c6 48 89 c7 e8 2f b1 cf 08 31 c0 c3 0f 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 cc cc cc cc cc cc cc cc cc cc cc cc 55 <41> 57 41 56 53 b0 01 48 85 f6 0f 84 9a 01 00 00 48 89 fd 48 01 f5 RSP: 0018:ffffc900001e0d28 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff8179eef2 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8ea09f28 RBP: 0000000000000001 R08: ffffffff8179eece R09: fffffbfff2ec1012 R10: 0000000000000000 R11: dffffc0000000001 R12: 1bc16d674ec99afb R13: ffff8880b8f2a6c0 R14: ffff8880b8f2a4c0 R15: dffffc0000000000 FS: 00007f1f8a5d96c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdbafad56c0 CR3: 0000000026ba7000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:72 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] cpumask_test_cpu include/linux/cpumask.h:444 [inline] cpu_online include/linux/cpumask.h:1030 [inline] trace_hrtimer_cancel include/trace/events/timer.h:297 [inline] debug_deactivate+0x82/0x280 kernel/time/hrtimer.c:483 __run_hrtimer kernel/time/hrtimer.c:1657 [inline] __hrtimer_run_queues+0x334/0xe50 kernel/time/hrtimer.c:1753 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1815 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline] __sysvec_apic_timer_interrupt+0x158/0x5b0 arch/x86/kernel/apic/apic.c:1124 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666 Code: 2b 00 74 08 4c 89 f7 e8 9f 49 77 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc9000503f7c0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000a07f04 RCX: ffffffff816b6102 RDX: dffffc0000000000 RSI: ffffffff8b0c2ec0 RDI: ffffffff8b5f6d80 RBP: ffffc9000503f910 R08: dffffc0000000000 R09: fffffbfff2256c53 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000a07f00 R13: dffffc0000000000 R14: ffffc9000503f820 R15: 0000000000000246 __might_fault+0xbd/0x110 mm/memory.c:5851 _copy_from_user+0x26/0x170 lib/usercopy.c:14 copy_from_user include/linux/uaccess.h:161 [inline] copy_msghdr_from_user+0xaa/0x670 net/socket.c:2449 recvmsg_copy_msghdr net/socket.c:2704 [inline] ___sys_recvmsg net/socket.c:2776 [inline] do_recvmmsg+0x408/0xad0 net/socket.c:2874 __sys_recvmmsg net/socket.c:2953 [inline] __do_sys_recvmmsg net/socket.c:2976 [inline] __se_sys_recvmmsg net/socket.c:2969 [inline] __x64_sys_recvmmsg+0x195/0x240 net/socket.c:2969 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f1f8978d169 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:00007f1f8a5d9038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f1f899a6080 RCX: 00007f1f8978d169 RDX: 0000000000010106 RSI: 00004000000000c0 RDI: 0000000000000003 RBP: 00007f1f8980e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f1f899a6080 R15: 00007ffffaef8ab8