[moderation] [kernel?] KCSAN: data-race in hrtimer_interrupt / print_tickdevice (15)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 9946eaf552b1 Merge tag 'hardening-v6.14-rc2' of git://git...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=179d02a4580000
kernel config: https://syzkaller.appspot.com/x/.config?x=9e757e3762bd630b
dashboard link: https://syzkaller.appspot.com/bug?extid=82c16afe4c8d9e71876e
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/f8a295bc0113/disk-9946eaf5.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9bf127abb398/vmlinux-9946eaf5.xz
kernel image: https://storage.googleapis.com/syzbot-assets/22a6d155000c/bzImage-9946eaf5.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+82c16a...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in hrtimer_interrupt / print_tickdevice

write to 0xffff888237d1c218 of 8 bytes by interrupt on cpu 1:
hrtimer_interrupt+0x80/0x4a0 kernel/time/hrtimer.c:1906
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
__sysvec_apic_timer_interrupt+0x5c/0x1d0 arch/x86/kernel/apic/apic.c:1055
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0x32/0x80 arch/x86/kernel/apic/apic.c:1049
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702

read to 0xffff888237d1c218 of 8 bytes by task 17525 on cpu 0:
print_tickdevice+0x144/0x340 kernel/time/timer_list.c:208
timer_list_show+0x79/0x180 kernel/time/timer_list.c:300
seq_read_iter+0x655/0x930 fs/seq_file.c:272
proc_reg_read_iter+0x118/0x190 fs/proc/inode.c:299
copy_splice_read+0x383/0x5b0 fs/splice.c:365
do_splice_read fs/splice.c:985 [inline]
splice_direct_to_actor+0x269/0x670 fs/splice.c:1089
do_splice_direct_actor fs/splice.c:1207 [inline]
do_splice_direct+0xd7/0x150 fs/splice.c:1233
do_sendfile+0x398/0x660 fs/read_write.c:1363
__do_sys_sendfile64 fs/read_write.c:1424 [inline]
__se_sys_sendfile64 fs/read_write.c:1410 [inline]
__x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1410
x64_sys_call+0xfbd/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:41
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: 0x0000002a5f730580 -> 0x7fffffffffffffff

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 17525 Comm: syz.3.6147 Tainted: G W 6.14.0-rc1-syzkaller-00235-g9946eaf552b1 #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
==================================================================


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[syzbot]

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