syzbot

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BUG: KCSAN: data-race in __sys_setsockopt / smc_switch_to_fallback

write to 0xffff8881120797a0 of 8 bytes by task 3840 on cpu 1:
 smc_switch_to_fallback+0x4de/0x7f0 net/smc/af_smc.c:914
 smc_setsockopt+0x524/0x7a0 net/smc/af_smc.c:3087
 do_sock_setsockopt net/socket.c:2334 [inline]
 __sys_setsockopt+0x1cc/0x240 net/socket.c:2357
 __do_sys_setsockopt net/socket.c:2366 [inline]
 __se_sys_setsockopt net/socket.c:2363 [inline]
 __x64_sys_setsockopt+0x66/0x80 net/socket.c:2363
 x64_sys_call+0x278d/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:55
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881120797a0 of 8 bytes by task 3836 on cpu 0:
 sock_from_file net/socket.c:513 [inline]
 sockfd_lookup_light net/socket.c:559 [inline]
 __sys_setsockopt+0xa7/0x240 net/socket.c:2353
 __do_sys_setsockopt net/socket.c:2366 [inline]
 __se_sys_setsockopt net/socket.c:2363 [inline]
 __x64_sys_setsockopt+0x66/0x80 net/socket.c:2363
 x64_sys_call+0x278d/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:55
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff8881066a1d40 -> 0xffff8881066a0680

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3836 Comm: syz.4.106 Not tainted 6.12.0-rc4-syzkaller-00261-g850925a8133c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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