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INFO: rcu detected stall in sys_io_uring_setup

Status: auto-obsoleted due to no activity on 2023/10/03 12:32
Subsystems: cgroups mm
[Documentation on labels]
First crash: 1002d, last: 1002d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_io_uring_setup (3) mm 1 2 128d 191d 0/29 auto-obsoleted due to no activity on 2026/03/26 06:52
linux-5.15 INFO: rcu detected stall in io_uring_setup 1 1 119d 119d 0/3 auto-obsoleted due to no activity on 2026/04/13 23:07
upstream INFO: rcu detected stall in sys_io_uring_setup (2) io-uring mm 1 2 509d 552d 0/29 auto-obsoleted due to no activity on 2025/03/10 01:00
upstream INFO: rcu detected stall in io_uring_setup bpf io-uring 1 2 290d 298d 0/29 auto-obsoleted due to no activity on 2025/10/14 19:03

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4491/1:b..l P29007/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=77093, q=97 ncpus=2)
task:syz-executor.1  state:R  running task     stack:29448 pid:29007 ppid:5076   flags:0x00000002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0xee1/0x59f0 kernel/sched/core.c:6711
 preempt_schedule_irq+0x52/0x90 kernel/sched/core.c:7023
 irqentry_exit+0x35/0x80 kernel/entry/common.c:433
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:task_css.constprop.0+0x50/0x130 include/linux/cgroup.h:436
Code: 00 48 8b ab 30 13 00 00 e8 4d 26 56 08 85 c0 75 26 48 8d 7d 20 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 c3 00 00 00 48 8b 45 20 5b 5d c3 e8 9e 51 8c ff 85 c0 75 d1
RSP: 0018:ffffc9000a257c80 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffff888037098000 RCX: 0000000000000000
RDX: 1ffff1100f67ff04 RSI: ffffffff8ac889a0 RDI: ffff88807b3ff820
RBP: ffff88807b3ff800 R08: 0000000000000000 R09: fffffbfff1d598ca
R10: ffffffff8eacc657 R11: 0000000000094000 R12: ffff888142e68b40
R13: 0000000000000cc0 R14: ffffffff882262a5 R15: ffff88814326a810
 mem_cgroup_from_task mm/memcontrol.c:1009 [inline]
 get_obj_cgroup_from_current+0x119/0x270 mm/memcontrol.c:3030
 memcg_slab_pre_alloc_hook mm/slab.h:487 [inline]
 slab_pre_alloc_hook mm/slab.h:714 [inline]
 slab_alloc_node mm/slub.c:3460 [inline]
 slab_alloc mm/slub.c:3486 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3493 [inline]
 kmem_cache_alloc_lru+0x9b/0x630 mm/slub.c:3509
 alloc_inode_sb include/linux/fs.h:2850 [inline]
 sock_alloc_inode+0x25/0x1c0 net/socket.c:307
 alloc_inode+0x5d/0x220 fs/inode.c:260
 new_inode_pseudo+0x16/0x80 fs/inode.c:1018
 sock_alloc+0x40/0x270 net/socket.c:633
 __sock_create+0xbc/0x810 net/socket.c:1502
 io_uring_get_file io_uring/io_uring.c:3813 [inline]
 io_uring_create io_uring/io_uring.c:4002 [inline]
 io_uring_setup+0x1a7a/0x2450 io_uring/io_uring.c:4061
 __do_sys_io_uring_setup io_uring/io_uring.c:4077 [inline]
 __se_sys_io_uring_setup io_uring/io_uring.c:4071 [inline]
 __x64_sys_io_uring_setup+0xc1/0xf0 io_uring/io_uring.c:4071
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7ffbaf67cae9
RSP: 002b:00007ffbb04470c8 EFLAGS: 00000246 ORIG_RAX: 00000000000001a9
RAX: ffffffffffffffda RBX: 00007ffbaf79bf80 RCX: 00007ffbaf67cae9
RDX: 0000000000000000 RSI: 0000000020000000 RDI: 00000000000030d5
RBP: 00007ffbaf6c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007ffbaf79bf80 R15: 00007ffd543917c8
 </TASK>
task:udevd           state:R  running task     stack:25296 pid:4491  ppid:1      flags:0x00000002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0xee1/0x59f0 kernel/sched/core.c:6711
 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6880
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0x5d/0x70 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 __wake_up_common_lock+0xe3/0x140 kernel/sched/wait.c:140
 sock_def_readable+0x158/0x760 net/core/sock.c:3313
 __netlink_sendskb net/netlink/af_netlink.c:1291 [inline]
 netlink_sendskb net/netlink/af_netlink.c:1297 [inline]
 netlink_unicast+0x6e2/0x800 net/netlink/af_netlink.c:1385
 netlink_sendmsg+0x93c/0xe40 net/netlink/af_netlink.c:1939
 sock_sendmsg_nosec net/socket.c:727 [inline]
 sock_sendmsg+0xd9/0x180 net/socket.c:750
 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2496
 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2550
 __sys_sendmsg+0x117/0x1e0 net/socket.c:2579
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f836f724a4b
RSP: 002b:00007ffd4a65faf8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00005561acf7fdf0 RCX: 00007f836f724a4b
RDX: 0000000000000000 RSI: 00007ffd4a65fb08 RDI: 0000000000000004
RBP: 00005561acfde9a0 R08: 0000000000000001 R09: 8f8bdc1335262708
R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000088 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 10558 jiffies! g77093 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:28928 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0xee1/0x59f0 kernel/sched/core.c:6711
 schedule+0xe7/0x1b0 kernel/sched/core.c:6787
 schedule_timeout+0x157/0x2c0 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x1ec/0xa50 kernel/rcu/tree.c:1613
 rcu_gp_kthread+0x249/0x380 kernel/rcu/tree.c:1812
 kthread+0x33a/0x430 kernel/kthread.c:389
 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.5.0-rc4-next-20230804-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
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+0x1b/0x20 drivers/acpi/processor_idle.c:113
Code: ed c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 65 48 8b 04 25 40 bc 03 00 48 8b 00 a8 08 75 0c 66 90 0f 00 2d c7 29 9b 00 fb f4 <fa> c3 0f 1f 00 0f b6 47 08 3c 01 74 0b 3c 02 74 05 8b 7f 04 eb 9f
RSP: 0018:ffffc90000177d60 EFLAGS: 00000246
RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8a38745e
RDX: 0000000000000001 RSI: ffff8880132e2800 RDI: ffff8880132e2864
RBP: ffff8880132e2864 R08: 0000000000000000 R09: ffffed1017326dad
R10: ffff8880b9936d6b R11: 0000000000000001 R12: ffff8881426d4000
R13: ffffffff8d45a160 R14: 0000000000000001 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6a3f29ddd8 CR3: 0000000018fae000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:707
 cpuidle_enter_state+0x82/0x500 drivers/cpuidle/cpuidle.c:267
 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388
 cpuidle_idle_call kernel/sched/idle.c:215 [inline]
 do_idle+0x315/0x3f0 kernel/sched/idle.c:282
 cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:379
 start_secondary+0x200/0x290 arch/x86/kernel/smpboot.c:326
 secondary_startup_64_no_verify+0x167/0x16b
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/08/04 12:25 linux-next bdffb18b5dd8 74621247 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in sys_io_uring_setup
* Struck through repros no longer work on HEAD.