Hello, syzbot found the following issue on: HEAD commit: 56fb6f92854f Merge tag 'drm-next-2024-05-25' of https://gi.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=127ed4b2980000 kernel config: https://syzkaller.appspot.com/x/.config?x=48c05addbb27f3b0 dashboard link: https://syzkaller.appspot.com/bug?extid=3acfdc6a28244a4f4039 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/4428368407e9/disk-56fb6f92.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/d250915da349/vmlinux-56fb6f92.xz kernel image: https://storage.googleapis.com/syzbot-assets/d7d2d995f217/bzImage-56fb6f92.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+3acfdc6a28244a4f4039@xxxxxxxxxxxxxxxxxxxxxxxxx rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P62/2:b..l P5270/1:b..l P5260/1:b..l rcu: (detected by 1, t=10503 jiffies, g=9633, q=1038 ncpus=2) task:syz-executor.5 state:R running task stack:25776 pid:5260 tgid:5257 ppid:5110 flags:0x00004002 Call Trace: <TASK> context_switch kernel/sched/core.c:5408 [inline] __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7067 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:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5758 Code: 2b 00 74 08 4c 89 f7 e8 ca 7e 89 00 f6 44 24 61 02 0f 85 85 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:ffffc90003c9f520 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000793eb0 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: ffffffff8bcaca00 RDI: ffffffff8c1fe480 RBP: ffffc90003c9f680 R08: ffffffff92fa8587 R09: 1ffffffff25f50b0 R10: dffffc0000000000 R11: fffffbfff25f50b1 R12: 1ffff92000793eac R13: dffffc0000000000 R14: ffffc90003c9f580 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:329 [inline] rcu_read_lock include/linux/rcupdate.h:781 [inline] percpu_ref_get_many+0x36/0x140 include/linux/percpu-refcount.h:202 percpu_ref_get include/linux/percpu-refcount.h:222 [inline] css_get include/linux/cgroup_refcnt.h:11 [inline] mem_cgroup_commit_charge+0x9f/0x380 mm/memcontrol.c:3132 charge_memcg+0xb1/0x160 mm/memcontrol.c:7501 __mem_cgroup_charge+0x27/0x80 mm/memcontrol.c:7512 mem_cgroup_charge include/linux/memcontrol.h:691 [inline] shmem_alloc_and_add_folio+0x394/0xdb0 mm/shmem.c:1677 shmem_get_folio_gfp+0x82d/0x1f50 mm/shmem.c:2055 shmem_get_folio mm/shmem.c:2160 [inline] shmem_write_begin+0x170/0x4d0 mm/shmem.c:2743 generic_perform_write+0x324/0x640 mm/filemap.c:4015 shmem_file_write_iter+0xfc/0x120 mm/shmem.c:2919 new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa74/0xc90 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 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: 0033:0x7fe4ac07bc2f RSP: 002b:00007fe4ace12e80 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007fe4ac07bc2f RDX: 0000000001000000 RSI: 00007fe4a1e00000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000000050e7 R10: 0000000000000002 R11: 0000000000000293 R12: 0000000000000003 R13: 00007fe4ace12f80 R14: 00007fe4ace12f40 R15: 00007fe4a1e00000 </TASK> task:syz-executor.0 state:R running task stack:25360 pid:5270 tgid:5269 ppid:5112 flags:0x00000002 Call Trace: <TASK> context_switch kernel/sched/core.c:5408 [inline] __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7067 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:200 Code: 89 fb e8 23 00 00 00 48 8b 3d ec 8d 45 0c 48 89 de 5b e9 b3 4c 5a 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 00 d5 03 00 65 8b 15 10 c0 RSP: 0000:ffffc90003d07cd0 EFLAGS: 00000282 RAX: fffffffffffffff9 RBX: 00007f1a930e9000 RCX: ffff88801fd05a00 RDX: ffffc90009e3b000 RSI: 00007f1a930e9000 RDI: 0000001b32d1ffff RBP: 0000000000000004 R08: ffffffff8b7a9ef8 R09: ffffffff8b7a9d42 R10: 0000000000000003 R11: ffff88801fd05a00 R12: ffff8880225ac028 R13: 0000001b32d1ffff R14: ffff8880225ac008 R15: fffffffffffffff5 mtree_range_walk+0x2c4/0x8e0 lib/maple_tree.c:2781 mas_state_walk lib/maple_tree.c:3678 [inline] mas_walk+0x83/0x280 lib/maple_tree.c:4909 lock_vma_under_rcu+0x231/0x6e0 mm/memory.c:5840 do_user_addr_fault arch/x86/mm/fault.c:1329 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x17b/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f1a9d228800 RSP: 002b:00007f1a9dfda530 EFLAGS: 00010282 RAX: 00000000000e9000 RBX: 00007f1a9dfda5d0 RCX: 0000000000000016 RDX: 000000000000007f RSI: 0000000000000200 RDI: 00007f1a9dfda670 RBP: 00000000000000e8 R08: 00007f1a93000000 R09: 00000000000000fe R10: 0000000000000000 R11: 00007f1a9dfda5e0 R12: 0000000000000181 R13: 00007f1a9d2ebfc0 R14: 0000000000000011 R15: 00007f1a9dfda670 </TASK> task:kworker/u8:4 state:R running task stack:22992 pid:62 tgid:62 ppid:2 flags:0x00004000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: <TASK> context_switch kernel/sched/core.c:5408 [inline] __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6924 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6948 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0x179/0x200 kernel/softirq.c:389 neigh_forced_gc net/core/neighbour.c:293 [inline] neigh_alloc net/core/neighbour.c:485 [inline] ___neigh_create+0x5b5/0x2470 net/core/neighbour.c:648 ip6_finish_output2+0x1629/0x1670 net/ipv6/ip6_output.c:128 ip6_finish_output+0x41e/0x810 net/ipv6/ip6_output.c:222 NF_HOOK include/linux/netfilter.h:314 [inline] ndisc_send_skb+0xab0/0x1380 net/ipv6/ndisc.c:509 addrconf_dad_completed+0x76c/0xcd0 net/ipv6/addrconf.c:4359 addrconf_dad_work+0xdc2/0x16f0 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2e/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd70 kernel/workqueue.c:3393 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/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 10588 jiffies! g9633 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:25936 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: <TASK> context_switch kernel/sched/core.c:5408 [inline] __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6837 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2000 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2202 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/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: CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.9.0-syzkaller-12277-g56fb6f92854f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:72 [inline] RIP: 0010:acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:113 Code: 90 90 90 90 90 90 90 90 90 65 48 8b 04 25 00 d5 03 00 48 f7 00 08 00 00 00 75 10 eb 07 0f 00 2d b5 56 a3 00 f3 0f 1e fa fb f4 <fa> e9 54 23 2a 00 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 RSP: 0018:ffffc900001a7d08 EFLAGS: 00000246 RAX: ffff8880176a8000 RBX: ffff8880186af064 RCX: 0000000000053c99 RDX: 0000000000000001 RSI: ffff8880186af000 RDI: ffff8880186af064 RBP: 000000000003a5b8 R08: ffff8880b9537d0b R09: 1ffff110172a6fa1 R10: dffffc0000000000 R11: ffffffff8b861960 R12: ffff88801a384000 R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff8eacd960 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f17cddd3000 CR3: 0000000079cca000 CR4: 0000000000350ef0 Call Trace: <IRQ> </IRQ> <TASK> acpi_idle_enter+0xe4/0x140 drivers/acpi/processor_idle.c:707 cpuidle_enter_state+0x114/0x480 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x5d/0xa0 drivers/cpuidle/cpuidle.c:388 call_cpuidle kernel/sched/idle.c:155 [inline] cpuidle_idle_call kernel/sched/idle.c:236 [inline] do_idle+0x375/0x5d0 kernel/sched/idle.c:332 cpu_startup_entry+0x42/0x60 kernel/sched/idle.c:430 start_secondary+0x100/0x100 arch/x86/kernel/smpboot.c:313 common_startup_64+0x13e/0x147 </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 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