Hello, syzbot found the following issue on: HEAD commit: 6d858708d465 Merge branch 'net-ethernet-freescale-use-pa-t.. git tree: net-next console output: https://syzkaller.appspot.com/x/log.txt?x=119e7287980000 kernel config: https://syzkaller.appspot.com/x/.config?x=e7f0cac6eaefe81d dashboard link: https://syzkaller.appspot.com/bug?extid=bb0c3b50c40032b58091 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13d44230580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15666f57980000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/88c678a36ec8/disk-6d858708.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/b19b4fbbd593/vmlinux-6d858708.xz kernel image: https://storage.googleapis.com/syzbot-assets/18fef9c3fe20/bzImage-6d858708.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+bb0c3b50c40032b58091@xxxxxxxxxxxxxxxxxxxxxxxxx sched: DL replenish lagged too much rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P2/1:b..l rcu: (detected by 0, t=10503 jiffies, g=7697, q=2518875 ncpus=2) task:kthreadd state:R running task stack:24560 pid:2 tgid:2 ppid:0 flags:0x00004000 Call Trace: <TASK> context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6682 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7004 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:check_kcov_mode kernel/kcov.c:194 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x37/0x70 kernel/kcov.c:217 Code: 00 d8 03 00 65 8b 15 a0 f0 6e 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 1c 16 00 00 00 74 2c 8b 91 f8 15 00 00 <83> fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc RSP: 0018:ffffc900000775d0 EFLAGS: 00000246 RAX: ffffffff820b6c02 RBX: dffffc0000000000 RCX: ffff8881404a9e00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000040 RBP: dffffc0000000000 R08: ffffffff820b6bd8 R09: 1ffffffff2859900 R10: dffffc0000000000 R11: fffffbfff2859901 R12: ffff88801e1605d0 R13: 1ffffffff34887b4 R14: 0000000000000000 R15: 0000000000000000 __page_table_check_zero+0x102/0x350 mm/page_table_check.c:153 page_table_check_free include/linux/page_table_check.h:41 [inline] free_pages_prepare mm/page_alloc.c:1109 [inline] free_unref_page+0xd0f/0xf20 mm/page_alloc.c:2638 discard_slab mm/slub.c:2677 [inline] __put_partials+0xeb/0x130 mm/slub.c:3145 put_cpu_partial+0x17c/0x250 mm/slub.c:3220 __slab_free+0x2ea/0x3d0 mm/slub.c:4449 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_kmalloc+0x23/0xb0 mm/kasan/common.c:385 kasan_kmalloc include/linux/kasan.h:257 [inline] __do_kmalloc_node mm/slub.c:4264 [inline] __kmalloc_noprof+0x1fc/0x400 mm/slub.c:4276 kmalloc_noprof include/linux/slab.h:882 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] lsm_blob_alloc security/security.c:685 [inline] lsm_cred_alloc security/security.c:702 [inline] security_prepare_creds+0x53/0x360 security/security.c:3240 prepare_creds+0x467/0x640 kernel/cred.c:242 copy_creds+0x109/0x9c0 kernel/cred.c:312 copy_process+0x9df/0x3d50 kernel/fork.c:2237 kernel_clone+0x226/0x8f0 kernel/fork.c:2784 kernel_thread+0x1bc/0x240 kernel/fork.c:2846 create_kthread kernel/kthread.c:412 [inline] kthreadd+0x60d/0x810 kernel/kthread.c:767 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> rcu: rcu_preempt kthread starved for 9045 jiffies! g7697 f0x2 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:21840 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: <TASK> context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6774 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 </TASK> rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 24 Comm: ksoftirqd/1 Not tainted 6.12.0-rc2-syzkaller-00631-g6d858708d465 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:check_preemption_disabled+0x42/0x120 lib/smp_processor_id.c:55 Code: 08 65 8b 1d dc d2 3c 74 65 8b 05 d1 d2 3c 74 a9 ff ff ff 7f 74 26 65 48 8b 04 25 28 00 00 00 48 3b 44 24 08 0f 85 ce 00 00 00 <89> d8 48 83 c4 10 5b 41 5c 41 5e 41 5f c3 cc cc cc cc 48 c7 04 24 RSP: 0018:ffffc900001e69e8 EFLAGS: 00000246 RAX: bcc40fbadd619200 RBX: 0000000000000001 RCX: ffffffff817056d4 RDX: 0000000000000000 RSI: ffffffff8c60fb00 RDI: ffffffff8c60fac0 RBP: ffffc900001e6b88 R08: ffffffff901d11af R09: 1ffffffff203a235 R10: dffffc0000000000 R11: fffffbfff203a236 R12: 1ffff9200003cd50 R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff8a4c39a4 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3e012ad198 CR3: 000000000e734000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <NMI> </NMI> <TASK> rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:737 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0xe3/0x550 kernel/locking/lockdep.c:5796 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] l3mdev_master_ifindex include/net/l3mdev.h:69 [inline] ip_route_me_harder+0x571/0x1360 net/ipv4/netfilter.c:49 synproxy_send_tcp+0x356/0x6c0 net/netfilter/nf_synproxy_core.c:431 synproxy_send_client_synack+0x8b8/0xf30 net/netfilter/nf_synproxy_core.c:484 nft_synproxy_eval_v4+0x3ca/0x610 net/netfilter/nft_synproxy.c:59 nft_synproxy_do_eval+0x362/0xa60 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline] nft_do_chain+0x4ad/0x1da0 net/netfilter/nf_tables_core.c:288 nft_do_chain_inet+0x418/0x6b0 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x29e/0x450 include/linux/netfilter.h:312 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5668 [inline] __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5781 process_backlog+0x662/0x15b0 net/core/dev.c:6113 __napi_poll+0xcb/0x490 net/core/dev.c:6834 napi_poll net/core/dev.c:6903 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:7025 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 </TASK> --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
