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From:   Ard Biesheuvel <ard.biesheuvel@linaro.org>
Date:   Sat, 17 Nov 2018 06:52:38 -0800
Message-ID: <CAKv+Gu8tJZUgL7q0R2KvGdyK+_y1U7KHQNDMpCmM7ZGprkKajg@mail.gmail.com>
Subject: Re: WARNING in static_key_disable_cpuslocked
To:     syzbot+6cffdef928852907751c@syzkaller.appspotmail.com,
        pabeni@redhat.com, "David S. Miller" <davem@davemloft.net>
Cc:     Borislav Petkov <bp@suse.de>, Jason Baron <jbaron@akamai.com>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        syzkaller-bugs@googlegroups.com,
        Thomas Gleixner <tglx@linutronix.de>
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(+ Paolo, Dave)

On Sat, 17 Nov 2018 at 01:59, syzbot
<syzbot+6cffdef928852907751c@syzkaller.appspotmail.com> wrote:
>
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit:    442b8cea2477 Add linux-next specific files for 20181109
> git tree:       linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=11f1dc25400000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=2f72bdb11df9fbe8
> dashboard link: https://syzkaller.appspot.com/bug?extid=6cffdef928852907751c
> compiler:       gcc (GCC) 8.0.1 20180413 (experimental)
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=10126533400000
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+6cffdef928852907751c@syzkaller.appspotmail.com
>
> IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready
> IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready
> 8021q: adding VLAN 0 to HW filter on device team0
> 8021q: adding VLAN 0 to HW filter on device team0
> hrtimer: interrupt took 32101 ns
> WARNING: CPU: 0 PID: 7564 at kernel/jump_label.c:188
> static_key_disable_cpuslocked+0x2bb/0x310 kernel/jump_label.c:188
> Kernel panic - not syncing: panic_on_warn set ...
> CPU: 0 PID: 7564 Comm: syz-executor2 Not tainted 4.20.0-rc1-next-20181109+
> #110
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> Google 01/01/2011
> Call Trace:
>   __dump_stack lib/dump_stack.c:77 [inline]
>   dump_stack+0x244/0x39d lib/dump_stack.c:113
>   panic+0x2ad/0x55c kernel/panic.c:188
>   __warn.cold.8+0x20/0x45 kernel/panic.c:540
>   report_bug+0x254/0x2d0 lib/bug.c:186
>   fixup_bug arch/x86/kernel/traps.c:178 [inline]
>   do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:271
>   do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:290
>   invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:969
> RIP: 0010:static_key_disable_cpuslocked+0x2bb/0x310 kernel/jump_label.c:188
> Code: ff eb db e8 07 da e3 ff 48 89 da 48 c7 c6 00 bf 31 88 48 c7 c7 e0 bb
> 31 88 e8 71 0d ad ff 0f 0b e9 0e fe ff ff e8 e5 d9 e3 ff <0f> 0b e9 2b ff
> ff ff 4c 89 f7 e8 56 32 27 00 e9 5e fe ff ff 48 89
> RSP: 0018:ffff8801ba2b7928 EFLAGS: 00010293
> RAX: ffff8801bb558340 RBX: 00000000ffffffff RCX: ffffffff819bcdf5
> RDX: 0000000000000000 RSI: ffffffff819bcecb RDI: 0000000000000005
> RBP: ffff8801ba2b79f0 R08: ffff8801bb558340 R09: fffffbfff17885c4
> R10: fffffbfff17885c4 R11: ffffffff8bc42e23 R12: 1ffff10037456f25
> R13: 1ffff10037456f31 R14: dffffc0000000000 R15: ffff8801ba2b79c8
>   static_key_disable+0x1a/0x30 kernel/jump_label.c:202
>   udpv6_destroy_sock+0x1e3/0x220 net/ipv6/udp.c:1492
>   sk_common_release+0x6d/0x320 net/core/sock.c:3001
>   udp_lib_close+0x15/0x20 include/net/udp.h:206
>   inet_release+0x104/0x1f0 net/ipv4/af_inet.c:428
>   inet6_release+0x50/0x70 net/ipv6/af_inet6.c:458
>   __sock_release+0xd7/0x250 net/socket.c:580
>   sock_close+0x19/0x20 net/socket.c:1142
>   __fput+0x3bc/0xa70 fs/file_table.c:279
>   ____fput+0x15/0x20 fs/file_table.c:312
>   task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
>   tracehook_notify_resume include/linux/tracehook.h:188 [inline]
>   exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166
>   prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
>   syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
>   do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
>   entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x411021
> Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 34 19 00 00 c3 48
> 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48
> 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
> RSP: 002b:00007ffeb03ec0a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
> RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000411021
> RDX: 0000000000000001 RSI: 0000000000731ce8 RDI: 0000000000000003
> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
> R10: 00007ffeb03ebfd0 R11: 0000000000000293 R12: 0000000000000000
> R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000002
> Kernel Offset: disabled
> Rebooting in 86400 seconds..
>
>
> ---
> This bug is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@googlegroups.com.
>
> syzbot will keep track of this bug report. See:
> https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with
> syzbot.
> syzbot can test patches for this bug, for details see:
> https://goo.gl/tpsmEJ#testing-patches