rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4373/1:b..l P12985/1:b..l
(detected by 0, t=10502 jiffies, g=83281, q=71 ncpus=2)
task:syz.8.1600 state:R running task stack:26496 pid:12985 ppid:8532 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
irqentry_exit+0x63/0x70 kernel/entry/common.c:439
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__sanitizer_cov_trace_switch+0x0/0xe0 kernel/kcov.c:329
Code: 28 4d 39 ca 77 1e 49 ff c0 4c 89 02 48 c7 44 0a 08 07 00 00 00 48 89 7c 0a 10 48 89 74 0a 18 48 89 44 0a 20 c3 0f 1f 44 00 00 <48> 8b 4e 08 48 83 c1 f8 48 c1 c1 3d 48 83 f9 07 0f 87 c1 00 00 00
RSP: 0018:ffffc900050af8b8 EFLAGS: 00000246
RAX: ffffffff8a0523f1 RBX: 0000000000000000 RCX: ffff88802eee0000
RDX: 0000000000000000 RSI: ffffffff8e084c50 RDI: ffff88807c0d641c
RBP: ffffc900050af9d0 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c449 R11: 1ffffffff215c448 R12: dffffc0000000000
R13: ffff88807c0d641c R14: ffffffffffffff00 R15: 0000000000000002
mas_state_walk lib/maple_tree.c:3895 [inline]
mt_find+0x211/0x810 lib/maple_tree.c:6537
find_vma mm/mmap.c:1898 [inline]
__vma_adjust+0x1cd/0x1c60 mm/mmap.c:627
vma_adjust include/linux/mm.h:2810 [inline]
__split_vma+0x3a7/0x500 mm/mmap.c:-1
mprotect_fixup+0x4f2/0x7f0 mm/mprotect.c:617
do_mprotect_pkey+0x754/0xa40 mm/mprotect.c:792
__do_sys_mprotect mm/mprotect.c:819 [inline]
__se_sys_mprotect mm/mprotect.c:816 [inline]
__x64_sys_mprotect+0x7c/0x90 mm/mprotect.c:816
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: 0033:0x7fb060b8ef87
RSP: 002b:00007ffdbd1f52b8 EFLAGS: 00000206 ORIG_RAX: 000000000000000a
RAX: ffffffffffffffda RBX: 00007fb061b086c0 RCX: 00007fb060b8ef87
RDX: 0000000000000003 RSI: 0000000000020000 RDI: 00007fb061ae9000
RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000
R10: 0000000000021000 R11: 0000000000000206 R12: 00007ffdbd1f5410
R13: ffffffffffffffc0 R14: 0000000000001000 R15: 0000000000000000
task:udevd state:R running task stack:23040 pid:4373 ppid:3637 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
irqentry_exit+0x63/0x70 kernel/entry/common.c:439
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:xas_start+0x2ec/0x770 lib/xarray.c:-1
Code: 0f 94 c0 48 81 fb 01 10 00 00 40 0f 93 c5 40 20 c5 49 83 c6 08 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 <74> 08 4c 89 f7 e8 2a a8 c6 f7 4d 8b 36 40 84 ed 74 71 4c 8d 63 fe
RSP: 0018:ffffc900045177b0 EFLAGS: 00000246
RAX: 1ffff920008a2eff RBX: ffff8880178798c2 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000002
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c449 R11: 1ffffffff215c448 R12: 0000000000000002
R13: ffffc90004517808 R14: ffffc900045177f8 R15: 1ffff920008a2f01
xas_load lib/xarray.c:235 [inline]
xa_load+0x122/0x2e0 lib/xarray.c:1463
page_cache_ra_unbounded+0x143/0x770 mm/readahead.c:231
do_page_cache_ra mm/readahead.c:300 [inline]
force_page_cache_ra mm/readahead.c:331 [inline]
page_cache_sync_ra+0x3d7/0x490 mm/readahead.c:713
page_cache_sync_readahead include/linux/pagemap.h:1248 [inline]
filemap_get_pages mm/filemap.c:2665 [inline]
filemap_read+0x5ff/0x2f80 mm/filemap.c:2759
blkdev_read_iter+0x3d5/0x500 block/fops.c:614
call_read_iter include/linux/fs.h:2259 [inline]
new_sync_read fs/read_write.c:389 [inline]
vfs_read+0x434/0x920 fs/read_write.c:470
ksys_read+0x143/0x240 fs/read_write.c:613
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: 0033:0x7fb5b62a7407
RSP: 002b:00007ffce0ac7d40 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007fb5b6a0a880 RCX: 00007fb5b62a7407
RDX: 0000000000040000 RSI: 00007fb5b69a0000 RDI: 0000000000000009
RBP: 000055d9180f5f80 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 000055d9180e96f8 R15: 00007fb5b6b3139c
rcu: rcu_preempt kthread starved for 10563 jiffies! g83281 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:27544 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:
CPU: 0 PID: 12974 Comm: syz.4.1598 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:raw_spin_rq_unlock_irq+0x13/0x90 kernel/sched/sched.h:1368
Code: 7c d2 e8 10 32 77 00 eb cb 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 66 90 41 57 41 56 53 66 90 e8 b4 df c7 08 e8 ff 60 2d 00 fb 5b <41> 5e 41 5f c3 49 be 00 00 00 00 00 fc ff df 49 89 ff 48 8d 9f 58
RSP: 0018:ffffc90005177928 EFLAGS: 00000282
RAX: e7e896ff28be8300 RBX: ffffffff8c5de908 RCX: e7e896ff28be8300
RDX: dffffc0000000000 RSI: ffffffff8a8c0500 RDI: ffffffff8adefd20
RBP: ffffc90005177ac8 R08: dffffc0000000000 R09: ffffed10171c7559
R10: ffffed10171c7559 R11: 1ffff110171c7558 R12: ffff88802b180000
R13: dffffc0000000000 R14: ffff8880b8e3aac0 R15: ffff88802b180000
FS: 00007fa3b43866c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb5b69a1000 CR3: 0000000044eec000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__schedule+0x137c/0x40b0 kernel/sched/core.c:6567
schedule+0xb9/0x180 kernel/sched/core.c:6637
futex_wait_queue+0x134/0x1b0 kernel/futex/waitwake.c:355
futex_wait+0x19b/0x530 kernel/futex/waitwake.c:656
do_futex+0x310/0x320 kernel/futex/syscalls.c:106
__do_sys_futex kernel/futex/syscalls.c:183 [inline]
__se_sys_futex+0x14a/0x440 kernel/futex/syscalls.c:164
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: 0033:0x7fa3b358eec9
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:00007fa3b43860e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007fa3b37e6098 RCX: 00007fa3b358eec9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fa3b37e6098
RBP: 00007fa3b37e6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa3b37e6128 R14: 00007fff54736340 R15: 00007fff54736428