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BUG: KCSAN: data-race in page_pool_put_unrefed_netmem / page_pool_release

write to 0xffff88811a7d1880 of 8 bytes by task 21880 on cpu 0:
 __ptr_ring_zero_tail include/linux/ptr_ring.h:259 [inline]
 __ptr_ring_discard_one include/linux/ptr_ring.h:291 [inline]
 __ptr_ring_consume include/linux/ptr_ring.h:311 [inline]
 ptr_ring_consume_bh include/linux/ptr_ring.h:376 [inline]
 page_pool_empty_ring net/core/page_pool.c:1077 [inline]
 page_pool_scrub net/core/page_pool.c:1149 [inline]
 page_pool_release+0x28a/0x880 net/core/page_pool.c:1157
 page_pool_destroy+0x202/0x370 net/core/page_pool.c:1266
 xdp_test_run_teardown net/bpf/test_run.c:218 [inline]
 bpf_test_run_xdp_live+0xfe8/0x1050 net/bpf/test_run.c:396
 bpf_prog_test_run_xdp+0x59a/0x970 net/bpf/test_run.c:1331
 bpf_prog_test_run+0x22a/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 0xffff88811a7d1880 of 8 bytes by task 21886 on cpu 1:
 __ptr_ring_produce include/linux/ptr_ring.h:106 [inline]
 page_pool_recycle_in_ring net/core/page_pool.c:752 [inline]
 page_pool_put_unrefed_netmem+0x38b/0x4b0 net/core/page_pool.c:873
 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:998
 skb_pp_recycle net/core/skbuff.c:1009 [inline]
 skb_free_head+0x12c/0x150 net/core/skbuff.c:1056
 skb_release_data+0x33b/0x370 net/core/skbuff.c:1087
 skb_release_all net/core/skbuff.c:1152 [inline]
 __kfree_skb+0x44/0x150 net/core/skbuff.c:1166
 sk_skb_reason_drop+0xbd/0x270 net/core/skbuff.c:1204
 kfree_skb_reason include/linux/skbuff.h:1322 [inline]
 udpv6_recvmsg+0x1f7/0xca0 net/ipv6/udp.c:591
 inet6_recvmsg+0x143/0x290 net/ipv6/af_inet6.c:678
 sock_recvmsg_nosec net/socket.c:1078 [inline]
 sock_recvmsg+0x95/0x170 net/socket.c:1100
 ____sys_recvmsg+0xf5/0x280 net/socket.c:2850
 ___sys_recvmsg+0x11f/0x370 net/socket.c:2892
 do_recvmmsg+0x1ef/0x540 net/socket.c:2987
 __sys_recvmmsg net/socket.c:3061 [inline]
 __do_sys_recvmmsg net/socket.c:3084 [inline]
 __se_sys_recvmmsg net/socket.c:3077 [inline]
 __x64_sys_recvmmsg+0xe5/0x170 net/socket.c:3077
 x64_sys_call+0x27aa/0x3000 arch/x86/include/generated/asm/syscalls_64.h:300
 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: 0xffffea0004f66d00 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 21886 Comm: syz.7.7542 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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