[v5.15] INFO: rcu detected stall in mmap_file (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 43bb85222e53 Linux 5.15.193
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13399b12580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e1bb6d24ef2164eb
dashboard link: https://syzkaller.appspot.com/bug?extid=7452a1b0698e4c564298
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/0bc183664ae8/disk-43bb8522.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0fc2f6618934/vmlinux-43bb8522.xz
kernel image: https://storage.googleapis.com/syzbot-assets/af70b3957f4c/bzImage-43bb8522.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7452a1...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-....: (0 ticks this GP) idle=e2d/1/0x4000000000000002 softirq=83032/83033 fqs=5247
(detected by 1, t=10502 jiffies, g=121141, q=1702)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 24066 Comm: syz.8.5097 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:asm_sysvec_irq_work+0x0/0x20 arch/x86/include/asm/idtentry.h:707
Code: e9 a5 03 00 00 90 90 90 90 90 0f 01 ca fc 6a ff e8 a5 02 00 00 48 89 c4 48 89 e7 e8 0a c2 e8 ff e9 85 03 00 00 90 90 90 90 90 <0f> 01 ca fc 6a ff e8 85 02 00 00 48 89 c4 48 89 e7 e8 da c6 e8 ff
RSP: 0018:ffffc90000007ab8 EFLAGS: 00000006
RAX: 5a225237a18c1000 RBX: 1ffff92000000f60 RCX: 5a225237a18c1000
RDX: dffffc0000000000 RSI: ffffffff8a0b1820 RDI: ffffffff8a59a480
RBP: ffffc90000007bb8 R08: dffffc0000000000 R09: fffffbfff1ff781f
R10: fffffbfff1ff781f R11: 1ffffffff1ff781e R12: ffffffff8c120b00
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
FS: 0000555563552500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fefafa14778 CR3: 0000000052aaf000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
<IRQ>
RIP: 0010:rcu_read_unlock_special+0x84/0x480 kernel/rcu/tree_plugin.h:674
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 ad 13 9e 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc90000007ae0 EFLAGS: 00000206
__rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
rcu_read_unlock include/linux/rcupdate.h:771 [inline]
ieee80211_iterate_active_interfaces_atomic+0x132/0x140 net/mac80211/util.c:831
mac80211_hwsim_beacon+0x9b/0x180 drivers/net/wireless/mac80211_hwsim.c:1865
__run_hrtimer kernel/time/hrtimer.c:1690 [inline]
__hrtimer_run_queues+0x53d/0xc40 kernel/time/hrtimer.c:1754
hrtimer_run_softirq+0x176/0x240 kernel/time/hrtimer.c:1771
handle_softirqs+0x328/0x820 kernel/softirq.c:576
__do_softirq kernel/softirq.c:610 [inline]
invoke_softirq kernel/softirq.c:450 [inline]
__irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659
irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:unwind_next_frame+0x1197/0x1d90 arch/x86/kernel/unwind_orc.c:609
Code: ff df 48 8b 44 24 48 42 0f b6 04 28 84 c0 0f 85 30 08 00 00 8b 44 24 7c 39 03 0f 85 ff 00 00 00 48 8b 44 24 40 42 80 3c 28 00 <74> 0a 48 8b 7c 24 38 e8 2d a9 87 00 4c 8b 7b 38 48 8d 7b 08 48 89
RSP: 0018:ffffc900037df0e8 EFLAGS: 00000246
RAX: 1ffff920006fbe3c RBX: ffffc900037df1a8 RCX: 0000000000000000
RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900037df1f0 R08: dffffc0000000000 R09: ffffc900037df1f8
R10: fffff520006fbe41 R11: 1ffff920006fbe3f R12: 1ffffffff1bdc3e4
R13: dffffc0000000000 R14: ffffc900037df1f8 R15: ffffc900037df1dd
arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
save_stack+0xf3/0x1e0 mm/page_owner.c:119
__set_page_owner+0x41/0x2d0 mm/page_owner.c:181
prep_new_page mm/page_alloc.c:2426 [inline]
get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192
__alloc_pages+0x1e1/0x470 mm/page_alloc.c:5487
__get_free_pages+0x8/0x30 mm/page_alloc.c:5524
kasan_populate_vmalloc_pte+0x21/0xc0 mm/kasan/shadow.c:266
apply_to_pte_range mm/memory.c:2573 [inline]
apply_to_pmd_range mm/memory.c:2617 [inline]
apply_to_pud_range mm/memory.c:2653 [inline]
apply_to_p4d_range mm/memory.c:2689 [inline]
__apply_to_page_range+0x983/0xd10 mm/memory.c:2725
alloc_vmap_area+0x19f7/0x1b20 mm/vmalloc.c:1572
__get_vm_area_node+0x14f/0x2d0 mm/vmalloc.c:2430
__vmalloc_node_range+0xef/0x8b0 mm/vmalloc.c:3027
vmalloc_user+0x70/0x80 mm/vmalloc.c:3173
kcov_mmap+0x27/0x120 kernel/kcov.c:474
call_mmap include/linux/fs.h:2177 [inline]
mmap_file+0x5d/0xb0 mm/util.c:1092
__mmap_region mm/mmap.c:1796 [inline]
mmap_region+0xf8f/0x1660 mm/mmap.c:2933
do_mmap+0x81f/0xea0 mm/mmap.c:1586
vm_mmap_pgoff+0x1b2/0x2b0 mm/util.c:551
ksys_mmap_pgoff+0x542/0x780 mm/mmap.c:1635
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fb0bab46be3
Code: f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 41 89 ca 41 f7 c1 ff 0f 00 00 75 14 b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 25 c3 0f 1f 40 00 48 c7 c0 a8 ff ff ff 64 c7
RSP: 002b:00007ffdf1248198 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007fb0bad8e308 RCX: 00007fb0bab46be3
RDX: 0000000000000003 RSI: 0000000000400000 RDI: 00007fb0b894b000
RBP: 00007fb0bad8e270 R08: 00000000000000db R09: 0000000000000000
R10: 0000000000000011 R11: 0000000000000246 R12: 0000000000000003
R13: 00007fb0bad8e270 R14: 00000000000008e6 R15: 0000000000000003
</TASK>


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