rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=82dc/1/0x4000000000000000 softirq=25298/25299 fqs=29
rcu: (detected by 0, t=10502 jiffies, g=29993, q=429 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 8046 Comm: syz.5.780 Not tainted 6.6.98-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1784 [inline]
RIP: 0010:__hrtimer_run_queues+0x6a8/0xc40 kernel/time/hrtimer.c:1819
Code: 28 00 74 08 48 89 df e8 56 96 68 00 4c 39 23 75 4d e8 6c e7 0f 00 48 8b 44 24 38 42 80 3c 28 00 74 08 48 89 df e8 d8 96 68 00 <48> c7 03 00 00 00 00 48 8b 84 24 a8 00 00 00 42 80 3c 28 00 74 08
RSP: 0018:ffffc900001f0d40 EFLAGS: 00000046
RAX: 1ffff110171e5751 RBX: ffff8880b8f2ba88 RCX: ffff8880581e0000
RDX: 0000000000010000 RSI: 1ffff110171e574a RDI: ffff88801f7ab340
RBP: ffffc900001f0e90 R08: ffff88801f7ab357 R09: 0000000000000000
R10: ffff88801f7ab340 R11: ffffed1003ef566b R12: ffff88801f7ab340
R13: dffffc0000000000 R14: ffff8880b8f2ba98 R15: ffff8880b8f2ba40
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000003200 CR3: 000000000cb30000 CR4: 00000000003506e0
Call Trace:
hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1881
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline]
__sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__tlb_remove_page_size+0x67/0x490 mm/mmu_gather.c:129
Code: e8 0e d5 10 00 4d 8b 36 31 ff 4c 89 f6 e8 61 2a b8 ff 4d 85 f6 0f 84 0c 04 00 00 4d 8d 77 28 4c 89 f0 48 c1 e8 03 48 89 04 24 <80> 3c 18 00 74 08 4c 89 f7 e8 db d4 10 00 4c 89 74 24 08 4d 8b 26
RSP: 0018:ffffc9000cce7470 EFLAGS: 00000a02
RAX: 1ffff9200199cf19 RBX: dffffc0000000000 RCX: ffff8880581e0000
RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000000000000
RBP: ffffc9000cce76b0 R08: ffffea0000901347 R09: 1ffffd4000120268
R10: dffffc0000000000 R11: fffff94000120269 R12: 00007f767ae00000
R13: dffffc0000000000 R14: ffffc9000cce78c8 R15: ffffc9000cce78a0
__tlb_remove_page include/asm-generic/tlb.h:471 [inline]
zap_pte_range mm/memory.c:1457 [inline]
zap_pmd_range mm/memory.c:1570 [inline]
zap_pud_range mm/memory.c:1599 [inline]
zap_p4d_range mm/memory.c:1620 [inline]
unmap_page_range+0x168b/0x2fe0 mm/memory.c:1641
unmap_vmas+0x25e/0x3a0 mm/memory.c:1731
exit_mmap+0x200/0xb50 mm/mmap.c:3298
__mmput+0x118/0x3c0 kernel/fork.c:1355
exit_mm+0x1da/0x2c0 kernel/exit.c:569
do_exit+0x88e/0x23c0 kernel/exit.c:870
do_group_exit+0x21b/0x2d0 kernel/exit.c:1024
get_signal+0x12fc/0x1400 kernel/signal.c:2902
arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f767c58e929
Code: Unable to access opcode bytes at 0x7f767c58e8ff.
RSP: 002b:00007f767d30e0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007f767c7b5fa8 RCX: 00007f767c58e929
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f767c7b5fac
RBP: 00007f767c7b5fa0 R08: 0000000000745988 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 00007f767c7b5fac
R13: 0000000000000000 R14: 00007fffee37ca50 R15: 00007fffee37cb38
rcu: rcu_preempt kthread starved for 10355 jiffies! g29993 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
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:27056 pid:17 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x14e2/0x4580 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
schedule_timeout+0x160/0x280 kernel/time/timer.c:2167
rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667
rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1866
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 8054 Comm: syz.3.782 Not tainted 6.6.98-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline]
RIP: 0010:smp_call_function_many_cond+0xde4/0x1130 kernel/smp.c:855
Code: 89 ee 83 e6 01 31 ff e8 2a e7 0a 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 65 e3 0a 00 eb 38 f3 90 42 0f b6 04 2b <84> c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 49 e3 0a 00 eb e4 44
RSP: 0018:ffffc9000cde7660 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 1ffff110171e82f5 RCX: 0000000000080000
RDX: ffffc9000d92c000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc9000cde77c8 R08: ffffffff90da657f R09: 1ffffffff21b4caf
R10: dffffc0000000000 R11: fffffbfff21b4cb0 R12: ffff8880b8f417a8
R13: dffffc0000000000 R14: ffff8880b8e3d588 R15: 0000000000000001
FS: 00007ff7f87156c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff7f7971d60 CR3: 0000000074959000 CR4: 00000000003506f0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1023
kill_bdev block/bdev.c:75 [inline]
blkdev_flush_mapping+0x128/0x290 block/bdev.c:632
blkdev_put_whole block/bdev.c:663 [inline]
blkdev_put+0x498/0x760 block/bdev.c:941
btrfs_scan_one_device+0x266/0x610 fs/btrfs/volumes.c:1456
btrfs_mount_root+0x49a/0x920 fs/btrfs/super.c:1489
legacy_get_tree+0xea/0x180 fs/fs_context.c:662
vfs_get_tree+0x8c/0x280 fs/super.c:1764
fc_mount fs/namespace.c:1108 [inline]
vfs_kern_mount+0xbe/0x160 fs/namespace.c:1138
btrfs_mount+0x2e1/0xa70 fs/btrfs/super.c:1587
legacy_get_tree+0xea/0x180 fs/fs_context.c:662
vfs_get_tree+0x8c/0x280 fs/super.c:1764
do_new_mount+0x24b/0xa40 fs/namespace.c:3366
do_mount fs/namespace.c:3706 [inline]
__do_sys_mount fs/namespace.c:3915 [inline]
__se_sys_mount+0x2da/0x3c0 fs/namespace.c:3892
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7ff7f79900ca
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007ff7f8714e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ff7f8714ef0 RCX: 00007ff7f79900ca
RDX: 00002000000055c0 RSI: 0000200000005600 RDI: 00007ff7f8714eb0
RBP: 00002000000055c0 R08: 00007ff7f8714ef0 R09: 0000000000008400
R10: 0000000000008400 R11: 0000000000000246 R12: 0000200000005600
R13: 00007ff7f8714eb0 R14: 000000000000559a R15: 00002000000000c0