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BUG: KCSAN: data-race in page_pool_put_unrefed_netmem / page_pool_release

write to 0xffff88810483e500 of 8 bytes by task 11993 on cpu 1:
 __ptr_ring_discard_one include/linux/ptr_ring.h:280 [inline]
 __ptr_ring_consume include/linux/ptr_ring.h:301 [inline]
 ptr_ring_consume_bh include/linux/ptr_ring.h:366 [inline]
 page_pool_empty_ring net/core/page_pool.c:1075 [inline]
 page_pool_scrub net/core/page_pool.c:1147 [inline]
 page_pool_release+0x28d/0x860 net/core/page_pool.c:1155
 page_pool_destroy+0x202/0x370 net/core/page_pool.c:1264
 xdp_test_run_teardown net/bpf/test_run.c:218 [inline]
 bpf_test_run_xdp_live+0xfde/0x1050 net/bpf/test_run.c:396
 bpf_prog_test_run_xdp+0x59a/0x970 net/bpf/test_run.c:1331
 bpf_prog_test_run+0x227/0x390 kernel/bpf/syscall.c:4673
 __sys_bpf+0x4c0/0x7c0 kernel/bpf/syscall.c:6152
 __do_sys_bpf kernel/bpf/syscall.c:6244 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6242 [inline]
 __x64_sys_bpf+0x41/0x50 kernel/bpf/syscall.c:6242
 x64_sys_call+0x2aee/0x3000 arch/x86/include/generated/asm/syscalls_64.h:322
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88810483e500 of 8 bytes by task 11994 on cpu 0:
 __ptr_ring_produce include/linux/ptr_ring.h:106 [inline]
 page_pool_recycle_in_ring net/core/page_pool.c:750 [inline]
 page_pool_put_unrefed_netmem+0x38b/0x4b0 net/core/page_pool.c:871
 page_pool_put_netmem include/net/page_pool/helpers.h:343 [inline]
 page_pool_put_full_netmem include/net/page_pool/helpers.h:373 [inline]
 napi_pp_put_page+0xe9/0x200 net/core/skbuff.c:997
 skb_pp_recycle net/core/skbuff.c:1008 [inline]
 skb_free_head+0x12c/0x150 net/core/skbuff.c:1055
 skb_release_data+0x33b/0x370 net/core/skbuff.c:1086
 skb_release_all net/core/skbuff.c:1151 [inline]
 __kfree_skb+0x44/0x150 net/core/skbuff.c:1165
 sk_skb_reason_drop+0xbd/0x270 net/core/skbuff.c:1203
 kfree_skb_reason include/linux/skbuff.h:1275 [inline]
 __first_packet_length+0x320/0x3c0 net/ipv4/udp.c:1858
 first_packet_length+0x217/0x240 net/ipv4/udp.c:1889
 udp_poll+0xc8/0x150 net/ipv4/udp.c:3176
 sock_poll+0x20a/0x230 net/socket.c:1430
 vfs_poll include/linux/poll.h:82 [inline]
 select_poll_one fs/select.c:480 [inline]
 do_select+0x8ee/0xf40 fs/select.c:536
 core_sys_select+0x3d7/0x6e0 fs/select.c:677
 do_pselect fs/select.c:759 [inline]
 __do_sys_pselect6 fs/select.c:802 [inline]
 __se_sys_pselect6+0x216/0x280 fs/select.c:793
 __x64_sys_pselect6+0x78/0x90 fs/select.c:793
 x64_sys_call+0x28bd/0x3000 arch/x86/include/generated/asm/syscalls_64.h:271
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffffea000439b400 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 11994 Comm: syz.6.2864 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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