rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6460/1:b..l rcu: (detected by 1, t=10503 jiffies, g=9445, q=1117 ncpus=2) task:syz.4.143 state:R running task stack:23808 pid:6460 tgid:6460 ppid:5852 flags:0x00000006 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x18af/0x4bd0 kernel/sched/core.c:6690 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7012 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:get_current arch/x86/include/asm/current.h:49 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x8/0x90 kernel/kcov.c:321 Code: 44 0a 20 c3 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 4c 8b 04 24 <65> 48 8b 0c 25 c0 d5 03 00 65 8b 05 b0 f6 6e 7e 25 00 01 ff 00 74 RSP: 0018:ffffc900045874f8 EFLAGS: 00000202 RAX: 0000000000000000 RBX: 0000000000000043 RCX: ffff888026021e00 RDX: 0000000000000000 RSI: 0000000000000043 RDI: 0000000000000043 RBP: ffffc900045875b0 R08: ffffffff81ea71b0 R09: 1ffffffff285b700 R10: dffffc0000000000 R11: fffffbfff285b701 R12: 0000000000000000 R13: 000000005aaf2067 R14: dffffc0000000000 R15: 0000000000000000 pmd_bad arch/x86/include/asm/pgtable.h:1101 [inline] __pte_offset_map+0x2b0/0x380 mm/pgtable-generic.c:298 __pte_offset_map_lock+0xc7/0x300 mm/pgtable-generic.c:371 pte_offset_map_lock include/linux/mm.h:3014 [inline] __get_locked_pte mm/memory.c:1992 [inline] get_locked_pte include/linux/mm.h:2727 [inline] insert_page mm/memory.c:2076 [inline] vm_insert_page+0x4a9/0x710 mm/memory.c:2229 kcov_mmap+0xd7/0x140 kernel/kcov.c:506 call_mmap include/linux/fs.h:2172 [inline] mmap_region+0x1689/0x2940 mm/mmap.c:1449 do_mmap+0x8f0/0x1000 mm/mmap.c:496 vm_mmap_pgoff+0x1dd/0x3d0 mm/util.c:588 ksys_mmap_pgoff+0x4eb/0x720 mm/mmap.c:542 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ffa95d7e753 RSP: 002b:00007fffe9c60b48 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007ffa95f362a0 RCX: 00007ffa95d7e753 RDX: 0000000000000003 RSI: 0000000000200000 RDI: 00007ffa93401000 RBP: 00007ffa95f36208 R08: 00000000000000db R09: 0000000000000000 R10: 0000000000000011 R11: 0000000000000246 R12: 0000000000000003 R13: 00007ffa95f36208 R14: 0000000000000003 R15: 00000000000008d2 rcu: rcu_preempt kthread starved for 6309 jiffies! g9445 f0x0 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:25856 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x18af/0x4bd0 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6782 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.12.0-rc5-syzkaller-01229-g2a6f99ee1a80 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 RIP: 0010:__kasan_check_read+0xa/0x20 mm/kasan/shadow.c:31 Code: db eb d0 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 89 f6 48 8b 0c 24 <31> d2 e9 6f e6 ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 RSP: 0018:ffffc900001575e0 EFLAGS: 00000007 RAX: 000000000000001d RBX: 000000000000077b RCX: ffffffff8170bfba RDX: 0000000000000008 RSI: 0000000000000008 RDI: ffffffff942db8e8 RBP: 0000000000000008 R08: ffffffff942db8ef R09: 1ffffffff285b71d R10: dffffc0000000000 R11: fffffbfff285b71e R12: ffff88801ce8da00 R13: dffffc0000000000 R14: 0000000000000100 R15: ffff88801ce8e4e0 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe265c2942f CR3: 000000007a858000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] hlock_class kernel/locking/lockdep.c:228 [inline] mark_lock+0x9a/0x360 kernel/locking/lockdep.c:4703 mark_usage kernel/locking/lockdep.c:4646 [inline] __lock_acquire+0xc35/0x2050 kernel/locking/lockdep.c:5156 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] process_backlog+0x824/0x15b0 net/core/dev.c:6124 __napi_poll+0xcb/0x490 net/core/dev.c:6838 napi_poll net/core/dev.c:6907 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:7029 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 run_ksoftirqd+0xca/0x130 kernel/softirq.c:927 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 net_ratelimit: 18093 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:1b, 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 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 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 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) bridge0: received packet on veth0_to_bridge with own address as source address (addr:8a:cc:7a:18:cc:0c, vlan:0) net_ratelimit: 19755 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:1b, 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 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 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 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) bridge0: received packet on veth0_to_bridge with own address as source address (addr:8a:cc:7a:18:cc:0c, vlan:0)