WARNING in arch_install_hw

WARNING in arch_install_hw_breakpoint
Status: public: reported syz repro on 2019/04/14 09:28
Reported-by: syzbot+acfd3de78bec50ddcbf9@syzkaller.appspotmail.com
First crash: 307d, last: 190d

similar bugs (3):
Kernel	Title	Repro	Bisected	Count	Last	Reported	Patched	Status
android-414	WARNING in arch_install_hw_breakpoint	syz		2	308d	287d	0/1	public: reported syz repro on 2019/04/13 00:01
upstream	WARNING in arch_install_hw_breakpoint	C	cause+fix	8	190d	307d	0/16	upstream: reported C repro on 2019/03/24 06:22
linux-4.14	WARNING in arch_install_hw_breakpoint	syz		1	10d	190d	0/1	upstream: reported syz repro on 2019/07/19 00:15

Sample crash report:

------------[ cut here ]------------
WARNING: CPU: 0 PID: 20438 at arch/x86/kernel/hw_breakpoint.c:121 arch_install_hw_breakpoint+0xbe/0x300 /arch/x86/kernel/hw_breakpoint.c:121
Can't find any breakpoint slot[  258.485220] Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 20438 Comm: syz-executor.5 Not tainted 4.9.185+ #8
 ffff8801b4c6f538 ffffffff81b5a081 ffff8801b4c6f600 ffffffff82a3a9a0
 00000000ffffffff 0000000000000000 0000000000000009 ffff8801b4c6f618
 ffffffff813fd56a 0000000041b58ab3 ffffffff82e31752 ffffffff813fd391
Call Trace:
 [<000000001266fb41>] __dump_stack /lib/dump_stack.c:15 [inline]
 [<000000001266fb41>] dump_stack+0xc1/0x120 /lib/dump_stack.c:51
 [<00000000a2bf6dd0>] panic+0x1d9/0x3bd /kernel/panic.c:180
 [<0000000091f80080>] __warn.cold+0x2f/0x2f /kernel/panic.c:546
 [<000000002046d79d>] warn_slowpath_fmt+0xc2/0x100 /kernel/panic.c:569
 [<00000000c7ebddd0>] arch_install_hw_breakpoint+0xbe/0x300 /arch/x86/kernel/hw_breakpoint.c:121
 [<00000000779e3be5>] hw_breakpoint_add+0x90/0x120 /kernel/events/hw_breakpoint.c:574
 [<00000000e600fb24>] event_sched_in.isra.0+0x291/0x920 /kernel/events/core.c:2098
 [<000000002001bf2c>] group_sched_in+0x113/0x460 /kernel/events/core.c:2138
 [<000000009b5d294f>] ctx_flexible_sched_in /kernel/events/core.c:3079 [inline]
 [<000000009b5d294f>] ctx_sched_in.isra.0+0x54d/0xb20 /kernel/events/core.c:3125
 [<0000000017c85738>] perf_event_sched_in.isra.0+0x5d/0x90 /kernel/events/core.c:2265
 [<00000000159fb4d1>] perf_event_context_sched_in /kernel/events/core.c:3154 [inline]
 [<00000000159fb4d1>] __perf_event_task_sched_in+0x361/0x4a0 /kernel/events/core.c:3191
 [<000000004bcb07d5>] perf_event_task_sched_in /./include/linux/perf_event.h:1086 [inline]
 [<000000004bcb07d5>] finish_task_switch+0x21c/0x660 /kernel/sched/core.c:2812
 [<00000000a69e9347>] context_switch /kernel/sched/core.c:2946 [inline]
 [<00000000a69e9347>] __schedule+0x6d6/0x1f10 /kernel/sched/core.c:3491
 [<0000000026d353e7>] schedule+0x92/0x1c0 /kernel/sched/core.c:3546
 [<0000000073919fc7>] freezable_schedule /./include/linux/freezer.h:171 [inline]
 [<0000000073919fc7>] ptrace_stop+0x419/0x970 /kernel/signal.c:1914
 [<00000000afe56f5f>] do_jobctl_trap /kernel/signal.c:2133 [inline]
 [<00000000afe56f5f>] get_signal+0x13c4/0x1cb0 /kernel/signal.c:2261
 [<0000000036157532>] do_signal+0x9c/0x1920 /arch/x86/kernel/signal.c:812
 [<000000003350f615>] exit_to_usermode_loop+0x11c/0x160 /arch/x86/entry/common.c:159
 [<0000000078ae91f1>] prepare_exit_to_usermode /arch/x86/entry/common.c:195 [inline]
 [<0000000078ae91f1>] syscall_return_slowpath /arch/x86/entry/common.c:266 [inline]
 [<0000000078ae91f1>] do_syscall_64+0x3ab/0x5c0 /arch/x86/entry/common.c:293
 [<000000005f8b8147>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Shutting down cpus with NMI
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (3):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	Maintainers
ci-android-49-kasan-gce-root	2019/07/18 20:41	https://android.googlesource.com/kernel/common android-4.9	5e2c3408	7bb222f7	.config	log	report	syz	hpa@zytor.com, linux-kernel@vger.kernel.org, mingo@redhat.com, natechancellor@gmail.com, ndesaulniers@google.com, sashal@kernel.org, tglx@linutronix.de, x86@kernel.org
ci-android-49-kasan-gce-root	2019/03/23 11:35	https://android.googlesource.com/kernel/common android-4.9	270fbfb5	3361bde5	.config	log	report	syz	hpa@zytor.com, linux-kernel@vger.kernel.org, mingo@redhat.com, tglx@linutronix.de, x86@kernel.org
ci-android-49-kasan-gce-root	2019/07/18 19:49	https://android.googlesource.com/kernel/common android-4.9	5e2c3408	7bb222f7	.config	log	report		hpa@zytor.com, linux-kernel@vger.kernel.org, mingo@redhat.com, natechancellor@gmail.com, ndesaulniers@google.com, sashal@kernel.org, tglx@linutronix.de, x86@kernel.org