[moderation] [kernel?] KCSAN: data-race in __tmigr_cpu_activate / tmigr_handle_remote

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 855684c7d938 Merge tag 'x86_tdx_for_6.9' of git://git.kern..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12ee2c66180000
kernel config: https://syzkaller.appspot.com/x/.config?x=4984a7e0e4b69c26
dashboard link: https://syzkaller.appspot.com/bug?extid=e98be18c1a1b038b3b5a
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [jst...@google.com linux-...@vger.kernel.org sb...@kernel.org tg...@linutronix.de]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/e47477ed6466/disk-855684c7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/d9ad3879b897/vmlinux-855684c7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c8b609ab461e/bzImage-855684c7.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e98be1...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in __tmigr_cpu_activate / tmigr_handle_remote

write to 0xffff888237c2061c of 1 bytes by task 0 on cpu 0:
__tmigr_cpu_activate+0x55/0x1f0 kernel/time/timer_migration.c:682
tmigr_cpu_activate+0x8a/0xc0 kernel/time/timer_migration.c:705
timer_clear_idle+0x28/0x100 kernel/time/timer.c:2370
tick_nohz_restart_sched_tick+0x22/0x110 kernel/time/tick-sched.c:1088
tick_nohz_idle_update_tick kernel/time/tick-sched.c:1420 [inline]
tick_nohz_idle_exit+0xfe/0x1d0 kernel/time/tick-sched.c:1463
do_idle+0x1ee/0x230 kernel/sched/idle.c:345
cpu_startup_entry+0x25/0x30 kernel/sched/idle.c:430
rest_init+0xf3/0x100 init/main.c:730
arch_call_rest_init+0x9/0x10 init/main.c:831
start_kernel+0x57c/0x5e0 init/main.c:1077
x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555
x86_64_start_kernel+0x94/0xa0 arch/x86/kernel/head64.c:536
secondary_startup_64_no_verify+0x15f/0x16b

read to 0xffff888237c2061c of 1 bytes by interrupt on cpu 1:
tmigr_next_groupevt kernel/time/timer_migration.c:569 [inline]
tmigr_next_expired_groupevt kernel/time/timer_migration.c:593 [inline]
tmigr_handle_remote_up kernel/time/timer_migration.c:1013 [inline]
__walk_groups kernel/time/timer_migration.c:488 [inline]
tmigr_handle_remote+0x23f/0x8e0 kernel/time/timer_migration.c:1074
run_timer_softirq+0x5f/0x70 kernel/time/timer.c:2442
__do_softirq+0xc8/0x285 kernel/softirq.c:554
invoke_softirq kernel/softirq.c:428 [inline]
__irq_exit_rcu kernel/softirq.c:633 [inline]
irq_exit_rcu+0x3c/0x90 kernel/softirq.c:645
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
sysvec_apic_timer_interrupt+0x73/0x80 arch/x86/kernel/apic/apic.c:1043
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline]
acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:112
acpi_idle_do_entry+0x1d/0x30 drivers/acpi/processor_idle.c:573
acpi_idle_enter+0x96/0xb0 drivers/acpi/processor_idle.c:707
cpuidle_enter_state+0xd4/0x270 drivers/cpuidle/cpuidle.c:267
cpuidle_enter+0x40/0x70 drivers/cpuidle/cpuidle.c:388
call_cpuidle kernel/sched/idle.c:155 [inline]
cpuidle_idle_call kernel/sched/idle.c:236 [inline]
do_idle+0x195/0x230 kernel/sched/idle.c:332
cpu_startup_entry+0x25/0x30 kernel/sched/idle.c:430
start_secondary+0x94/0xa0 arch/x86/kernel/smpboot.c:313
secondary_startup_64_no_verify+0x15f/0x16b

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.8.0-syzkaller-01185-g855684c7d938 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
==================================================================


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