[moderation] [kernel?] KCSAN: data-race in __futex_wait / hrtimer_wakeup (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 6b0f8db921ab Merge tag 'execve-v6.11-rc4' of git://git.ker..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14a6af7d980000
kernel config: https://syzkaller.appspot.com/x/.config?x=31ece081c16313f0
dashboard link: https://syzkaller.appspot.com/bug?extid=89607689dadafe427d60
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [anna-...@linutronix.de fred...@kernel.org linux-...@vger.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/9863a413bbed/disk-6b0f8db9.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2d681ddbd546/vmlinux-6b0f8db9.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c52eddcef651/bzImage-6b0f8db9.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+896076...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in __futex_wait / hrtimer_wakeup

read-write to 0xffffc90001327eb8 of 8 bytes by interrupt on cpu 0:
hrtimer_wakeup+0x1c/0x50 kernel/time/hrtimer.c:1923
__run_hrtimer kernel/time/hrtimer.c:1689 [inline]
__hrtimer_run_queues+0x20d/0x5e0 kernel/time/hrtimer.c:1753
hrtimer_interrupt+0x210/0x7b0 kernel/time/hrtimer.c:1815
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline]
__sysvec_apic_timer_interrupt+0x5c/0x1a0 arch/x86/kernel/apic/apic.c:1049
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
sysvec_apic_timer_interrupt+0x6e/0x80 arch/x86/kernel/apic/apic.c:1043
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
__preempt_count_dec_and_test arch/x86/include/asm/preempt.h:94 [inline]
__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
_raw_spin_unlock_irq+0x2f/0x50 kernel/locking/spinlock.c:202
spin_unlock_irq include/linux/spinlock.h:401 [inline]
get_signal+0xc8e/0x1080 kernel/signal.c:2920
arch_do_signal_or_restart+0x95/0x4b0 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x59/0x130 kernel/entry/common.c:218
do_syscall_64+0xd6/0x1c0 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffc90001327eb8 of 8 bytes by task 9647 on cpu 1:
__futex_wait+0x17f/0x290 kernel/futex/waitwake.c:675
futex_wait kernel/futex/waitwake.c:697 [inline]
futex_wait_restart+0x131/0x260 kernel/futex/waitwake.c:731
__do_sys_restart_syscall+0x35/0x40 kernel/signal.c:3061
x64_sys_call+0x1803/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:220
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: 0xffff888116154200 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 9647 Comm: syz.0.1777 Not tainted 6.11.0-rc3-syzkaller-00013-g6b0f8db921ab #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.