KCSAN: data-race in uprobe_dispatcher / uprobe_dispatcher

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 73f3af7b4611 Merge branch 'akpm' (patches from Andrew)
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11a9ddce300000
kernel config: https://syzkaller.appspot.com/x/.config?x=f4e6864080265900
dashboard link: https://syzkaller.appspot.com/bug?extid=6736577b3b7f966618d0
compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.1
CC: [and...@kernel.org a...@kernel.org b...@vger.kernel.org dan...@iogearbox.net john.fa...@gmail.com ka...@fb.com kps...@kernel.org linux-...@vger.kernel.org mi...@redhat.com net...@vger.kernel.org ros...@goodmis.org songliu...@fb.com y...@fb.com]

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+673657...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in uprobe_dispatcher / uprobe_dispatcher

write to 0xffff888130181ae8 of 8 bytes by task 6969 on cpu 1:
uprobe_dispatcher+0x46/0x670 kernel/trace/trace_uprobe.c:1489
handler_chain kernel/events/uprobes.c:2083 [inline]
handle_swbp kernel/events/uprobes.c:2243 [inline]
uprobe_notify_resume+0x73a/0x1310 kernel/events/uprobes.c:2309
exit_to_user_mode_loop kernel/entry/common.c:166 [inline]
exit_to_user_mode_prepare+0xcb/0x190 kernel/entry/common.c:209
irqentry_exit_to_user_mode+0x5/0x10 kernel/entry/common.c:315
asm_exc_int3+0x31/0x40 arch/x86/include/asm/idtentry.h:567

read to 0xffff888130181ae8 of 8 bytes by task 7021 on cpu 0:
uprobe_dispatcher+0x37/0x670 kernel/trace/trace_uprobe.c:1489
handler_chain kernel/events/uprobes.c:2083 [inline]
handle_swbp kernel/events/uprobes.c:2243 [inline]
uprobe_notify_resume+0x73a/0x1310 kernel/events/uprobes.c:2309
exit_to_user_mode_loop kernel/entry/common.c:166 [inline]
exit_to_user_mode_prepare+0xcb/0x190 kernel/entry/common.c:209
irqentry_exit_to_user_mode+0x5/0x10 kernel/entry/common.c:315
asm_exc_int3+0x31/0x40 arch/x86/include/asm/idtentry.h:567

value changed: 0x0000000000004307 -> 0x0000000000004308

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7021 Comm: syz-executor.5 Not tainted 5.14.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================


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[syzbot]

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