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Message-ID: <02d29315-13ee-45c1-984e-13c98e88247b@linux.dev>
Date: Tue, 2 Apr 2024 20:59:10 -0700
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Subject: Re: [syzbot] [bpf?] KMSAN: uninit-value in trie_delete_elem
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To: Aleksandr Nogikh <nogikh@google.com>,
 Alexander Potapenko <glider@google.com>
Cc: syzbot <syzbot+603bcd9b0bf1d94dbb9b@syzkaller.appspotmail.com>,
 andrii@kernel.org, ast@kernel.org, bpf@vger.kernel.org,
 daniel@iogearbox.net, eddyz87@gmail.com, haoluo@google.com,
 john.fastabend@gmail.com, jolsa@kernel.org, kpsingh@kernel.org,
 linux-kernel@vger.kernel.org, martin.lau@linux.dev, sdf@google.com,
 song@kernel.org, syzkaller-bugs@googlegroups.com
References: <000000000000f9ce6d061494e694@google.com>
 <2ee098ec-a46f-44fa-8719-049331c4c206@linux.dev>
 <CANp29Y4WcXr7vd=cvdtxRWaPxOKzr97f9L+BXtm07AGGiW2j2A@mail.gmail.com>
From: Yonghong Song <yonghong.song@linux.dev>
In-Reply-To: <CANp29Y4WcXr7vd=cvdtxRWaPxOKzr97f9L+BXtm07AGGiW2j2A@mail.gmail.com>
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On 4/1/24 11:36 PM, Aleksandr Nogikh wrote:
> Hi,
>
> On Mon, Apr 1, 2024 at 8:55 PM Yonghong Song <yonghong.song@linux.dev> wrote:
>>
>> On 3/26/24 12:00 PM, syzbot wrote:
>>> Hello,
>>>
>>> syzbot found the following issue on:
>>>
>>> =====================================================
>>> BUG: KMSAN: uninit-value in trie_delete_elem+0xc0/0xbe0 kernel/bpf/lpm_trie.c:448
>> Unrelated to the bug itself, with KMSAN is enabled, qemu cannot boot my vm
>> any more. Anything special I need to do in order to boot a KMSAN kernel?
>>
> Does the kernel print any specific errors to the serial console while
> booting? Or nothing at all?

In my case, nothing at all.

>