rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (0 ticks this GP) idle=a21c/1/0x4000000000000002 softirq=32045/32045 fqs=0
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P10487
(detected by 0, t=10505 jiffies, g=40933, q=267 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 10487 Comm: syz.4.1822 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:130 [inline]
RIP: 0010:lock_acquire+0x1e7/0x490 kernel/locking/lockdep.c:5665
Code: 8c 8a e8 7c 75 b4 08 b8 ff ff ff ff 65 0f c1 05 7f 86 9f 7e 83 f8 01 0f 85 f9 00 00 00 48 c7 84 24 80 00 00 00 00 00 00 00 9c <8f> 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 00 00 00 41
RSP: 0018:ffffc9000da96d78 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 93274682ea87fa00
RDX: 0000000000000000 RSI: ffffffff8a8c1480 RDI: ffffffff8adefae0
RBP: ffffc9000da96e88 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c449 R11: 1ffffffff215c448 R12: 0000000000000001
R13: 1ffff92001b52dbc R14: 0000000000000046 R15: dffffc0000000000
FS: 00007fa90bc3b6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f71cff8 CR3: 000000001da74000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
rcu_read_lock_sched include/linux/rcupdate.h:883 [inline]
pfn_valid include/linux/mmzone.h:1857 [inline]
__virt_addr_valid+0x1a5/0x540 arch/x86/mm/physaddr.c:65
kasan_addr_to_slab+0x9/0xc0 mm/kasan/common.c:35
__kasan_record_aux_stack+0xf/0xc0 mm/kasan/generic.c:471
irq_work_queue_on+0x10f/0x260 kernel/irq_work.c:140
rcu_read_unlock_special+0x3c7/0x500 kernel/rcu/tree_plugin.h:678
__rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
rcu_read_unlock include/linux/rcupdate.h:823 [inline]
__perf_event_output kernel/events/core.c:7741 [inline]
perf_event_output_forward+0x237/0x2a0 kernel/events/core.c:7750
__perf_event_overflow+0x448/0x610 kernel/events/core.c:9496
perf_tp_event+0x335/0xb60 kernel/events/core.c:10029
perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10002
perf_trace_preemptirq_template+0x287/0x330 include/trace/events/preemptirq.h:14
trace_irq_enable_rcuidle+0xd3/0x140 include/trace/events/preemptirq.h:40
trace_hardirqs_on+0x24/0x40 kernel/trace/trace_preemptirq.c:44
asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:rcu_read_unlock_special+0x84/0x500 kernel/rcu/tree_plugin.h:685
Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 5d 97 96 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc9000da976a0 EFLAGS: 00000206
RAX: 93274682ea87fa00 RBX: 1ffff92001b52edc RCX: 93274682ea87fa00
RDX: dffffc0000000000 RSI: ffffffff8a8c0300 RDI: ffffffff8adefae0
RBP: ffffc9000da977a0 R08: dffffc0000000000 R09: fffffbfff215c45d
R10: fffffbfff215c45d R11: 1ffffffff215c45c R12: 0000000000000246
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff8cb30018
__rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
rcu_read_unlock include/linux/rcupdate.h:823 [inline]
d_alloc_parallel+0x119a/0x1480 fs/dcache.c:2734
lookup_open fs/namei.c:3407 [inline]
open_last_lookups fs/namei.c:3550 [inline]
path_openat+0x8fe/0x2e70 fs/namei.c:3780
do_filp_open+0x1c1/0x3c0 fs/namei.c:3810
do_sys_openat2+0x142/0x490 fs/open.c:1318
do_sys_open fs/open.c:1334 [inline]
__do_sys_openat fs/open.c:1350 [inline]
__se_sys_openat fs/open.c:1345 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1345
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fa90ad8ebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa90bc3b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fa90afc5fa0 RCX: 00007fa90ad8ebe9
RDX: 00000000000026e1 RSI: 0000200000000080 RDI: ffffffffffffff9c
RBP: 00007fa90ae11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa90afc6038 R14: 00007fa90afc5fa0 R15: 00007ffee199be78
task:syz.4.1822 state:R running task stack:23552 pid:10487 ppid:4266 flags:0x0000400c
Call Trace:
rcu: rcu_preempt kthread timer wakeup didn't happen for 10504 jiffies! g40933 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=1 timer-softirq=23021
rcu: rcu_preempt kthread starved for 10505 jiffies! g40933 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:26912 pid:16 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 10487 Comm: syz.4.1822 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:check_region_inline mm/kasan/generic.c:169 [inline]
RIP: 0010:kasan_check_range+0xd/0x290 mm/kasan/generic.c:189
Code: c3 0f 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 00 00 cc cc 00 00 cc cc 00 00 cc cc b0 01 48 85 f6 0f 84 a4 01 00 00 41 57 <41> 56 53 49 89 f8 49 01 f0 0f 82 57 02 00 00 49 89 f8 49 c1 e8 2f
RSP: 0018:ffffc9000da96d70 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff81637b69
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8e1f7268
RBP: ffffc9000da96e90 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c449 R11: 1ffffffff215c448 R12: 1ffff92001b52dbc
R13: dffffc0000000000 R14: 0000000000000001 R15: 1ffff92001b52dbc
FS: 00007fa90bc3b6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f71cff8 CR3: 000000001da74000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
instrument_atomic_read include/linux/instrumented.h:72 [inline]
_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
cpumask_test_cpu include/linux/cpumask.h:444 [inline]
cpu_online include/linux/cpumask.h:1030 [inline]
trace_lock_release include/trace/events/lock.h:69 [inline]
lock_release+0x819/0x910 kernel/locking/lockdep.c:5673
rcu_lock_release include/linux/rcupdate.h:355 [inline]
rcu_read_unlock_sched include/linux/rcupdate.h:904 [inline]
pfn_valid include/linux/mmzone.h:1867 [inline]
__virt_addr_valid+0x435/0x540 arch/x86/mm/physaddr.c:65
kasan_addr_to_slab+0x9/0xc0 mm/kasan/common.c:35
__kasan_record_aux_stack+0xf/0xc0 mm/kasan/generic.c:471
irq_work_queue_on+0x10f/0x260 kernel/irq_work.c:140
rcu_read_unlock_special+0x3c7/0x500 kernel/rcu/tree_plugin.h:678
__rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
rcu_read_unlock include/linux/rcupdate.h:823 [inline]
__perf_event_output kernel/events/core.c:7741 [inline]
perf_event_output_forward+0x237/0x2a0 kernel/events/core.c:7750
__perf_event_overflow+0x448/0x610 kernel/events/core.c:9496
perf_tp_event+0x335/0xb60 kernel/events/core.c:10029
perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10002
perf_trace_preemptirq_template+0x287/0x330 include/trace/events/preemptirq.h:14
trace_irq_enable_rcuidle+0xd3/0x140 include/trace/events/preemptirq.h:40
trace_hardirqs_on+0x24/0x40 kernel/trace/trace_preemptirq.c:44
asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:rcu_read_unlock_special+0x84/0x500 kernel/rcu/tree_plugin.h:685
Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 5d 97 96 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc9000da976a0 EFLAGS: 00000206
RAX: 93274682ea87fa00 RBX: 1ffff92001b52edc RCX: 93274682ea87fa00
RDX: dffffc0000000000 RSI: ffffffff8a8c0300 RDI: ffffffff8adefae0
RBP: ffffc9000da977a0 R08: dffffc0000000000 R09: fffffbfff215c45d
R10: fffffbfff215c45d R11: 1ffffffff215c45c R12: 0000000000000246
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff8cb30018
__rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
rcu_read_unlock include/linux/rcupdate.h:823 [inline]
d_alloc_parallel+0x119a/0x1480 fs/dcache.c:2734
lookup_open fs/namei.c:3407 [inline]
open_last_lookups fs/namei.c:3550 [inline]
path_openat+0x8fe/0x2e70 fs/namei.c:3780
do_filp_open+0x1c1/0x3c0 fs/namei.c:3810
do_sys_openat2+0x142/0x490 fs/open.c:1318
do_sys_open fs/open.c:1334 [inline]
__do_sys_openat fs/open.c:1350 [inline]
__se_sys_openat fs/open.c:1345 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1345
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fa90ad8ebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa90bc3b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fa90afc5fa0 RCX: 00007fa90ad8ebe9
RDX: 00000000000026e1 RSI: 0000200000000080 RDI: ffffffffffffff9c
RBP: 00007fa90ae11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa90afc6038 R14: 00007fa90afc5fa0 R15: 00007ffee199be78