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BUG: KCSAN: data-race in rxrpc_send_data / rxrpc_send_data_packet

write to 0xffff88811a8cd800 of 8 bytes by task 10214 on cpu 1:
 rxrpc_alloc_txqueue net/rxrpc/sendmsg.c:295 [inline]
 rxrpc_send_data+0x83e/0x14c0 net/rxrpc/sendmsg.c:399
 rxrpc_do_sendmsg+0xd94/0xe40 net/rxrpc/sendmsg.c:772
 rxrpc_sendmsg+0x46c/0x580 net/rxrpc/af_rxrpc.c:601
 sock_sendmsg_nosec net/socket.c:800 [inline]
 __sock_sendmsg net/socket.c:815 [inline]
 ____sys_sendmsg+0x532/0x580 net/socket.c:2713
 ___sys_sendmsg+0x195/0x1e0 net/socket.c:2767
 __sys_sendmsg net/socket.c:2799 [inline]
 __do_sys_sendmsg net/socket.c:2804 [inline]
 __se_sys_sendmsg net/socket.c:2802 [inline]
 __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2802
 x64_sys_call+0x22ab/0x2550 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88811a8cd800 of 8 bytes by task 10216 on cpu 0:
 rxrpc_prepare_data_packet net/rxrpc/output.c:566 [inline]
 rxrpc_send_data_packet+0x452/0x1d80 net/rxrpc/output.c:664
 rxrpc_transmit_fresh_data net/rxrpc/call_event.c:257 [inline]
 rxrpc_transmit_some_data+0x6e5/0x920 net/rxrpc/call_event.c:280
 rxrpc_input_call_event+0x862/0x11c0 net/rxrpc/call_event.c:404
 rxrpc_io_thread+0x1a60/0x1f90 net/rxrpc/io_thread.c:531
 kthread+0x223/0x270 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x0000000000000000 -> 0xffff88811ae61000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 10216 Comm: krxrpcio/0 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
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