WARNING in arch_install_hw_breakpoint

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: aea8526e Linux 4.14.133
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=14633b84600000
kernel config: https://syzkaller.appspot.com/x/.config?x=5dfccef5a159766b
dashboard link: https://syzkaller.appspot.com/bug?extid=bf749e036a2ef83f7175
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17dfdda4600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+bf749e...@syzkaller.appspotmail.com

Can't find any breakpoint slot
------------[ cut here ]------------
WARNING: CPU: 0 PID: 27774 at arch/x86/kernel/hw_breakpoint.c:121
arch_install_hw_breakpoint.cold+0x13/0x1f
/arch/x86/kernel/hw_breakpoint.c:121
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 27774 Comm: syz-executor.5 Not tainted 4.14.133 #28
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack /lib/dump_stack.c:17 [inline]
dump_stack+0x138/0x19c /lib/dump_stack.c:53
panic+0x1f2/0x426 /kernel/panic.c:182
__warn.cold+0x2f/0x36 /kernel/panic.c:546
report_bug+0x216/0x254 /lib/bug.c:186
fixup_bug /arch/x86/kernel/traps.c:177 [inline]
fixup_bug /arch/x86/kernel/traps.c:172 [inline]
do_error_trap+0x1bb/0x310 /arch/x86/kernel/traps.c:295
do_invalid_op+0x1b/0x20 /arch/x86/kernel/traps.c:314
invalid_op+0x1b/0x40 /arch/x86/entry/entry_64.S:960
RIP: 0010:arch_install_hw_breakpoint.cold+0x13/0x1f
/arch/x86/kernel/hw_breakpoint.c:121
RSP: 0018:ffff8881f3f9f818 EFLAGS: 00010082
RAX: 000000000000001e RBX: ffff8880aee1ecf8 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffed103e7f3ef9
RBP: ffff8881f3f9f858 R08: 000000000000001e R09: 0000000000000000
R10: 0000000000000000 R11: ffff8880808ae180 R12: ffff88808a05d2c0
R13: dffffc0000000000 R14: 0000000000000004 R15: 000000000001ed00
hw_breakpoint_add+0x90/0x120 /kernel/events/hw_breakpoint.c:574
event_sched_in.isra.0+0x3c7/0xba0 /kernel/events/core.c:2128
group_sched_in+0x110/0x450 /kernel/events/core.c:2168
ctx_flexible_sched_in /kernel/events/core.c:3193 [inline]
ctx_sched_in+0x909/0x1700 /kernel/events/core.c:3239
perf_event_sched_in+0x6e/0xa0 /kernel/events/core.c:2326
perf_event_context_sched_in /kernel/events/core.c:3279 [inline]
__perf_event_task_sched_in+0x574/0x7c0 /kernel/events/core.c:3318
perf_event_task_sched_in /./include/linux/perf_event.h:1087 [inline]
finish_task_switch+0x3e7/0x650 /kernel/sched/core.c:2663
context_switch /kernel/sched/core.c:2810 [inline]
__schedule+0x7c0/0x1cd0 /kernel/sched/core.c:3383
schedule+0x92/0x1c0 /kernel/sched/core.c:3427
freezable_schedule /./include/linux/freezer.h:172 [inline]
ptrace_stop+0x41a/0x950 /kernel/signal.c:1942
do_jobctl_trap /kernel/signal.c:2161 [inline]
get_signal+0x1401/0x1cd0 /kernel/signal.c:2288
do_signal+0x86/0x19a0 /arch/x86/kernel/signal.c:814
exit_to_usermode_loop+0x15c/0x220 /arch/x86/entry/common.c:160
prepare_exit_to_usermode /arch/x86/entry/common.c:199 [inline]
syscall_return_slowpath /arch/x86/entry/common.c:270 [inline]
do_syscall_64+0x4bc/0x640 /arch/x86/entry/common.c:297
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x459819
RSP: 002b:00007fadbba62c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000129
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000459819
RDX: 0000000000000016 RSI: 0000000000000b17 RDI: 0000000000000b17
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020000100 R11: 0000000000000246 R12: 00007fadbba636d4
R13: 00000000004c6cd6 R14: 00000000004dbf68 R15: 00000000ffffffff

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