toolchain: LLVM 11.0.0
config: defconfig + kcsan.config
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BUG: KCSAN: data-race in tick_nohz_idle_stop_tick / tick_nohz_idle_stop_tick

write to 0xffffa9cccf029bf0 of 4 bytes by task 0 on cpu 6:
 tick_nohz_idle_stop_tick+0x188/0x468
 do_idle+0xf4/0x288
 cpu_startup_entry+0x24/0x28
 secondary_start_kernel+0x22c/0x25c
 __secondary_switched+0x90/0x94

read to 0xffffa9cccf029bf0 of 4 bytes by task 0 on cpu 7:
 tick_nohz_idle_stop_tick+0x174/0x468
 do_idle+0xf4/0x288
 cpu_startup_entry+0x24/0x28
 secondary_start_kernel+0x22c/0x25c
 __secondary_switched+0x90/0x94

value changed: 0x00000006 -> 0xffffffff

Reported by Kernel Concurrency Sanitizer on:
CPU: 7 PID: 0 Comm: swapper/7 Not tainted 5.16.0-rc4-00002-g5854738642b4 #1
Hardware name: linux,dummy-virt (DT)
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