Received-SPF: pass (google.com: domain of linux-kernel+bounces-127449-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.48.161 as permitted sender) client-ip=147.75.48.161;
Precedence: bulk
MIME-Version: 1.0
References: <000000000000f9ce6d061494e694@google.com> <2ee098ec-a46f-44fa-8719-049331c4c206@linux.dev>
In-Reply-To: <2ee098ec-a46f-44fa-8719-049331c4c206@linux.dev>
From: Aleksandr Nogikh <nogikh@google.com>
Date: Tue, 2 Apr 2024 08:36:44 +0200
Message-ID: <CANp29Y4WcXr7vd=cvdtxRWaPxOKzr97f9L+BXtm07AGGiW2j2A@mail.gmail.com>
Subject: Re: [syzbot] [bpf?] KMSAN: uninit-value in trie_delete_elem
To: Yonghong Song <yonghong.song@linux.dev>, 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
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

Hi,

On Mon, Apr 1, 2024 at 8:55=E2=80=AFPM Yonghong Song <yonghong.song@linux.d=
ev> wrote:
>
>
> On 3/26/24 12:00 PM, syzbot wrote:
> > Hello,
> >
> > syzbot found the following issue on:
> >
> > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D
> > 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 v=
m
> 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?

--=20
Aleksandr