dummy0 speed is unknown, defaulting to 1000
==================================================================
BUG: KCSAN: data-race in _prb_read_valid / prb_reserve

write to 0xffffffff86935bd8 of 88 bytes by interrupt on cpu 1:
 prb_reserve+0x696/0xaf0 kernel/printk/printk_ringbuffer.c:1635
 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2326
 vprintk_emit+0x178/0x650 kernel/printk/printk.c:2426
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2465
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x79/0xa0 kernel/printk/printk.c:2475
 dccp_invalid_packet+0x444/0x620 net/dccp/ipv4.c:770
 dccp_v4_rcv+0x25/0x11f0 net/dccp/ipv4.c:805
 ip_protocol_deliver_rcu+0x423/0x780 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x184/0x220 net/ipv4/ip_input.c:233
 NF_HOOK include/linux/netfilter.h:314 [inline]
 ip_local_deliver+0xe8/0x1c0 net/ipv4/ip_input.c:254
 dst_input include/net/dst.h:469 [inline]
 ip_rcv_finish+0x188/0x1a0 net/ipv4/ip_input.c:447
 NF_HOOK include/linux/netfilter.h:314 [inline]
 ip_rcv+0x62/0x140 net/ipv4/ip_input.c:567
 __netif_receive_skb_one_core net/core/dev.c:5887 [inline]
 __netif_receive_skb+0xff/0x270 net/core/dev.c:6000
 process_backlog+0x229/0x420 net/core/dev.c:6352
 __napi_poll+0x63/0x3a0 net/core/dev.c:7324
 napi_poll net/core/dev.c:7388 [inline]
 net_rx_action+0x38e/0x7b0 net/core/dev.c:7510
 handle_softirqs+0xba/0x290 kernel/softirq.c:579
 do_softirq+0x5d/0x90 kernel/softirq.c:480
 __local_bh_enable_ip+0x70/0x80 kernel/softirq.c:407
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 bpf_test_run+0x220/0x490 net/bpf/test_run.c:437
 bpf_prog_test_run_skb+0x834/0xbd0 net/bpf/test_run.c:1093
 bpf_prog_test_run+0x207/0x390 kernel/bpf/syscall.c:4427
 __sys_bpf+0x3dc/0x790 kernel/bpf/syscall.c:5852
 __do_sys_bpf kernel/bpf/syscall.c:5941 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5939 [inline]
 __x64_sys_bpf+0x41/0x50 kernel/bpf/syscall.c:5939
 x64_sys_call+0x2478/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:322
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff86935bd8 of 8 bytes by task 20049 on cpu 0:
 desc_read kernel/printk/printk_ringbuffer.c:486 [inline]
 desc_read_finalized_seq kernel/printk/printk_ringbuffer.c:1874 [inline]
 prb_read kernel/printk/printk_ringbuffer.c:1922 [inline]
 _prb_read_valid+0x1c4/0x920 kernel/printk/printk_ringbuffer.c:2113
 prb_read_valid+0x3c/0x60 kernel/printk/printk_ringbuffer.c:2185
 printk_get_next_message+0xc8/0x510 kernel/printk/printk.c:3005
 console_emit_next_record kernel/printk/printk.c:3092 [inline]
 console_flush_all+0x290/0x730 kernel/printk/printk.c:3226
 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
 console_unlock+0xa1/0x330 kernel/printk/printk.c:3325
 vprintk_emit+0x388/0x650 kernel/printk/printk.c:2450
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2465
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x79/0xa0 kernel/printk/printk.c:2475
 ib_get_eth_speed+0x33d/0x4b0 drivers/infiniband/core/verbs.c:2006
 siw_query_port+0x3a/0x2d0 drivers/infiniband/sw/siw/siw_verbs.c:179
 iw_query_port drivers/infiniband/core/device.c:2100 [inline]
 ib_query_port+0x393/0x3d0 drivers/infiniband/core/device.c:2141
 ib_setup_port_attrs+0x14a/0x1430 drivers/infiniband/core/sysfs.c:1429
 add_one_compat_dev+0x261/0x360 drivers/infiniband/core/device.c:968
 rdma_dev_init_net+0x182/0x210 drivers/infiniband/core/device.c:1184
 ops_init+0x22a/0x2e0 net/core/net_namespace.c:138
 setup_net+0x13b/0x5f0 net/core/net_namespace.c:364
 copy_net_ns+0x565/0x720 net/core/net_namespace.c:518
 create_new_namespaces+0x20e/0x410 kernel/nsproxy.c:110
 copy_namespaces+0x1ad/0x210 kernel/nsproxy.c:179
 copy_process+0xd1b/0x1f90 kernel/fork.c:2433
 kernel_clone+0x16c/0x5b0 kernel/fork.c:2845
 __do_sys_clone3 kernel/fork.c:3149 [inline]
 __se_sys_clone3+0x1c2/0x200 kernel/fork.c:3128
 __x64_sys_clone3+0x31/0x40 kernel/fork.c:3128
 x64_sys_call+0x10c9/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:436
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000003cb9 -> 0x0000000000005cb9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 20049 Comm: syz.6.10426 Not tainted 6.15.0-rc7-syzkaller-00144-gb1427432d3b6 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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