[v6.1] INFO: rcu detected stall in sock_alloc_file (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 1989cd3d56e2 Linux 6.1.167
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=12bfbaba580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f0605c5af04d7603
dashboard link: https://syzkaller.appspot.com/bug?extid=f74682e9cfcbf29e3c25
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3e0cf5574b81/disk-1989cd3d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0c1152de55b1/vmlinux-1989cd3d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3fe87e3166b1/bzImage-1989cd3d.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f74682...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 2680 jiffies s: 13885 root: 0x2/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5090 Comm: syz.0.211 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:244 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x4/0x80 kernel/kcov.c:313
Code: 77 22 89 ff 89 f6 49 ff c0 4c 89 01 48 c7 44 11 08 03 00 00 00 48 89 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 90 48 8b 04 24 <65> 48 8b 15 44 f7 7f 7e 65 8b 0d 45 f7 7f 7e 81 e1 00 01 ff 00 74
RSP: 0018:ffffc900001e0058 EFLAGS: 00000046
RAX: ffffffff813a12e5 RBX: 0000000000000102 RCX: ffff88802ab93b80
RDX: 0000000000000100 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: ffffffff8e1fdeef R09: 1ffffffff1c3fbdd
R10: dffffc0000000000 R11: fffffbfff1c3fbde R12: dffffc0000000000
R13: 0000000000000008 R14: ffffffff813a1008 R15: ffff88813fff92e0
FS: 00007f387b81c6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2783bc CR3: 0000000059a97000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
__virt_addr_valid+0x465/0x540 arch/x86/mm/physaddr.c:65
kasan_addr_to_slab+0x9/0xc0 mm/kasan/common.c:36
__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+0x3c9/0x510 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+0x271/0x2f0 kernel/events/core.c:7750
__perf_event_overflow+0x448/0x610 kernel/events/core.c:9496
perf_swevent_overflow+0x19b/0x230 kernel/events/core.c:9579
perf_swevent_event+0x458/0x570 kernel/events/core.c:-1
perf_tp_event+0x3e7/0xc30 kernel/events/core.c:10064
perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10032
perf_trace_preemptirq_template+0x268/0x320 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+0x7f/0x510 kernel/rcu/tree_plugin.h:685
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 d2 33 95 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc900001e09a0 EFLAGS: 00000206
RAX: 2fb45ab355fa5600 RBX: 1ffff9200003c13c RCX: 2fb45ab355fa5600
RDX: dffffc0000000000 RSI: ffffffff8a8c10a0 RDI: ffffffff8adf0d20
RBP: ffffc900001e0a98 R08: ffff8880b8f3580b R09: 1ffff110171e6b01
R10: dffffc0000000000 R11: ffffed10171e6b02 R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8f3b900 R15: 0000000000000002
__rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
rcu_read_unlock include/linux/rcupdate.h:823 [inline]
percpu_ref_put_many include/linux/percpu-refcount.h:337 [inline]
percpu_ref_put+0xc8/0x100 include/linux/percpu-refcount.h:351
obj_cgroup_put include/linux/memcontrol.h:795 [inline]
memcg_slab_free_hook+0x16d/0x1f0 mm/slab.h:572
slab_free mm/slub.c:3682 [inline]
kmem_cache_free+0xe0/0x290 mm/slub.c:3709
rcu_do_batch kernel/rcu/tree.c:2297 [inline]
rcu_core+0xa99/0x1740 kernel/rcu/tree.c:2557
handle_softirqs+0x2a1/0x930 kernel/softirq.c:596
__do_softirq kernel/softirq.c:630 [inline]
invoke_softirq kernel/softirq.c:470 [inline]
__irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679
irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:unwind_next_frame+0x3f8/0x20b0 arch/x86/kernel/unwind_orc.c:461
Code: 39 17 00 00 41 c6 06 01 49 c7 c4 20 86 89 8a 49 8d 6c 24 04 4d 8d 7c 24 05 48 89 e8 48 c1 e8 03 48 89 44 24 48 42 0f b6 04 28 <84> c0 0f 85 72 16 00 00 4c 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0
RSP: 0018:ffffc900032777d0 EFLAGS: 00000a06
RAX: 0000000000000000 RBX: ffffc900032778a8 RCX: ffffffff8e7f5c3c
RDX: ffffffff8f16f5bc RSI: ffffffff8e7f5c38 RDI: ffffffff81391adf
RBP: ffffffff8f16f5c0 R08: 0000000000000001 R09: 0000000000000008
R10: dffffc0000000000 R11: fffff5200064ef21 R12: ffffffff8f16f5bc
R13: dffffc0000000000 R14: ffffffff8e7f5c38 R15: ffffffff8f16f5c1
arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
__kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:329
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
slab_alloc_node mm/slub.c:3359 [inline]
slab_alloc mm/slub.c:3367 [inline]
__kmem_cache_alloc_lru mm/slub.c:3374 [inline]
kmem_cache_alloc_lru+0x11a/0x2e0 mm/slub.c:3390
__d_alloc+0x31/0x700 fs/dcache.c:1774
d_alloc_pseudo+0x19/0x70 fs/dcache.c:1906
alloc_file_pseudo+0xe0/0x200 fs/file_table.c:265
sock_alloc_file+0xb3/0x240 net/socket.c:467
__sys_socketpair+0x2cc/0x540 net/socket.c:1756
__do_sys_socketpair net/socket.c:1785 [inline]
__se_sys_socketpair net/socket.c:1782 [inline]
__x64_sys_socketpair+0x97/0xb0 net/socket.c:1782
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f387a99c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f387b81c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffffda RBX: 00007f387ac16090 RCX: 00007f387a99c819
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: 00007f387aa32c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000040 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f387ac16128 R14: 00007f387ac16090 R15: 00007ffdbd1131d8
</TASK>


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