rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4384/1:b..l (detected by 1, t=10503 jiffies, g=13265, q=7 ncpus=2) task:syz-executor.1 state:R running task stack:25272 pid:4384 ppid:3931 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x142d/0x4550 kernel/sched/core.c:6558 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870 irqentry_exit+0x53/0x80 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666 Code: 2b 00 74 08 4c 89 f7 e8 7f a9 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:ffffc90004cbf4c0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000997ea4 RCX: 1ffff92000997e44 RDX: dffffc0000000000 RSI: ffffffff8aec1340 RDI: ffffffff8b3d45e0 RBP: ffffc90004cbf620 R08: dffffc0000000000 R09: fffffbfff2093845 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000997ea0 R13: dffffc0000000000 R14: ffffc90004cbf520 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] blk_cgroup_congested+0x36/0x220 block/blk-cgroup.c:1997 __cgroup_throttle_swaprate+0x6d/0x1b0 mm/swapfile.c:3671 cgroup_throttle_swaprate include/linux/swap.h:662 [inline] folio_throttle_swaprate include/linux/swap.h:671 [inline] shmem_add_to_page_cache+0xb90/0x1e60 mm/shmem.c:717 shmem_get_folio_gfp+0x164e/0x3470 mm/shmem.c:1971 shmem_get_folio mm/shmem.c:2072 [inline] shmem_write_begin+0x16e/0x4e0 mm/shmem.c:2559 generic_perform_write+0x2fc/0x5e0 mm/filemap.c:3817 __generic_file_write_iter+0x176/0x400 mm/filemap.c:3945 generic_file_write_iter+0xab/0x310 mm/filemap.c:3977 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x7ae/0xba0 fs/read_write.c:584 ksys_write+0x19c/0x2c0 fs/read_write.c:637 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: 0033:0x7febb867bcaf RSP: 002b:00007febb9495e80 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007febb867bcaf RDX: 0000000001000000 RSI: 00007febaedf7000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000005598 R10: 0000000000000002 R11: 0000000000000293 R12: 0000000000000003 R13: 00007febb9495f80 R14: 00007febb9495f40 R15: 00007febaedf7000 rcu: rcu_preempt kthread starved for 10541 jiffies! g13265 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:27032 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x142d/0x4550 kernel/sched/core.c:6558 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870 irqentry_exit+0x53/0x80 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:preempt_count_add+0x0/0x180 kernel/sched/core.c:5698 Code: 48 8b 0c 24 80 e1 07 80 c1 03 38 c1 7c 97 48 8b 3c 24 e8 83 ba 83 00 eb 8c e9 f2 fe ff ff 66 2e 0f 1f 84 00 00 00 00 00 66 90 <41> 57 41 56 53 89 fb 48 c7 c0 60 41 c9 91 48 c1 e8 03 49 bf 00 00 RSP: 0018:ffffc90000157b90 EFLAGS: 00000202 RAX: 0000000000000001 RBX: 1ffff11027fd7b28 RCX: ffffffff8a938926 RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000001 RBP: ffffc90000157cb0 R08: dffffc0000000000 R09: ffffed1027fd7b29 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88813febd940 R13: 1ffff9200002af78 R14: ffff88813febebb8 R15: dffffc0000000000 schedule+0xb8/0x180 kernel/sched/core.c:6633 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:308 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 3931 Comm: syz-executor.1 Not tainted 6.1.92-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 RIP: 0010:finish_task_switch+0x1d3/0x810 kernel/sched/core.c:5124 Code: 37 0b 00 48 83 c4 08 4c 89 f7 e8 98 30 00 00 0f 1f 44 00 00 4c 89 f7 e8 7b 20 36 09 e8 36 26 32 00 fb 49 8d bc 24 f8 15 00 00 <48> 89 f8 48 c1 e8 03 49 bd 00 00 00 00 00 fc ff df 42 0f b6 04 28 RSP: 0018:ffffc9000529fa08 EFLAGS: 00000286 RAX: f04325e766ae7e00 RBX: ffff888022f68034 RCX: ffffffff91c94103 RDX: dffffc0000000000 RSI: ffffffff8aec01c0 RDI: ffff88805396d178 RBP: ffffc9000529fa50 R08: dffffc0000000000 R09: ffffed1017327541 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88805396bb80 R13: 1ffff110173276eb R14: ffff8880b993aa00 R15: ffff8880b993b758 FS: 0000555555587480(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f521000 CR3: 000000007ea3c000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: context_switch kernel/sched/core.c:5248 [inline] __schedule+0x1435/0x4550 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 do_nanosleep+0x192/0x5f0 kernel/time/hrtimer.c:2045 hrtimer_nanosleep+0x24d/0x490 kernel/time/hrtimer.c:2098 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1308 [inline] __se_sys_clock_nanosleep+0x323/0x3b0 kernel/time/posix-timers.c:1285 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: 0033:0x7febb86a8375 Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 f6 b9 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 4f ba ff ff 48 8b 04 24 48 83 c4 28 f7 d8 RSP: 002b:00007fffe2c50a80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 0000000000000030 RCX: 00007febb86a8375 RDX: 00007fffe2c50ac0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fffe2c50b3c R08: 0000000000000000 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032 R13: 000000000001f1ad R14: 000000000001f1ad R15: 0000000000000000