==================================================================
BUG: KCSAN: data-race in __sys_setsockopt / smc_sendmsg

write to 0xffff888100cb88c8 of 8 bytes by task 3174 on cpu 1:
 smc_switch_to_fallback net/smc/af_smc.c:515 [inline]
 smc_sendmsg+0x1c6/0x300 net/smc/af_smc.c:1973
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 ____sys_sendmsg+0x352/0x4c0 net/socket.c:2353
 ___sys_sendmsg net/socket.c:2407 [inline]
 __sys_sendmsg+0x1e2/0x260 net/socket.c:2440
 __do_sys_sendmsg net/socket.c:2449 [inline]
 __se_sys_sendmsg net/socket.c:2447 [inline]
 __x64_sys_sendmsg+0x42/0x50 net/socket.c:2447
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888100cb88c8 of 8 bytes by task 3191 on cpu 0:
 sock_from_file net/socket.c:456 [inline]
 sockfd_lookup_light net/socket.c:501 [inline]
 __sys_setsockopt+0x106/0x450 net/socket.c:2106
 __do_sys_setsockopt net/socket.c:2143 [inline]
 __se_sys_setsockopt net/socket.c:2140 [inline]
 __x64_sys_setsockopt+0x62/0x70 net/socket.c:2140
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3191 Comm: syz-executor.5 Not tainted 5.10.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 3191 Comm: syz-executor.5 Not tainted 5.10.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x116/0x15d lib/dump_stack.c:118
 panic+0x1e7/0x5fa kernel/panic.c:231
 kcsan_report+0x67b/0x680 kernel/kcsan/report.c:634
 kcsan_setup_watchpoint+0x46a/0x4d0 kernel/kcsan/core.c:568
 sock_from_file net/socket.c:456 [inline]
 sockfd_lookup_light net/socket.c:501 [inline]
 __sys_setsockopt+0x106/0x450 net/socket.c:2106
 __do_sys_setsockopt net/socket.c:2143 [inline]
 __se_sys_setsockopt net/socket.c:2140 [inline]
 __x64_sys_setsockopt+0x62/0x70 net/socket.c:2140
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45e0f9
Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f00bf688c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e0f9
RDX: 000000000000000d RSI: 0000000000000001 RDI: 0000000000000003
RBP: 000000000119c120 R08: 00000000000002cb R09: 0000000000000000
R10: 0000000020000080 R11: 0000000000000246 R12: 000000000119c0dc
R13: 00007fff522cba0f R14: 00007f00bf6899c0 R15: 000000000119c0dc
Kernel Offset: disabled
Rebooting in 86400 seconds..