netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
To: "Toke Høiland-Jørgensen" <toke@redhat.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>,
	Jesper Dangaard Brouer <brouer@redhat.com>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	syzbot <syzbot+30209ea299c09d8785c9@syzkaller.appspotmail.com>,
	ddstreet@ieee.org, Dmitry Vyukov <dvyukov@google.com>,
	LKML <linux-kernel@vger.kernel.org>,
	Network Development <netdev@vger.kernel.org>,
	syzkaller-bugs <syzkaller-bugs@googlegroups.com>,
	bpf <bpf@vger.kernel.org>, Yonghong Song <yhs@fb.com>
Subject: Re: unregister_netdevice: waiting for DEV to become free (2)
Date: Fri, 15 Nov 2019 18:43:36 +0900	[thread overview]
Message-ID: <6f69f704-b51d-c3cb-02c6-8e6eb93f4194@i-love.sakura.ne.jp> (raw)
In-Reply-To: <87imopgere.fsf@toke.dk>

Hello.

syzbot is still reporting that bpf(BPF_MAP_UPDATE_ELEM) causes
unregister_netdevice() to hang. It seems that commit 546ac1ffb70d25b5
("bpf: add devmap, a map for storing net device references") assigned
dtab->netdev_map[i] at dev_map_update_elem() but commit 6f9d451ab1a33728
("xdp: Add devmap_hash map type for looking up devices by hashed index")
forgot to assign dtab->netdev_map[idx] at __dev_map_hash_update_elem()
when dev is newly allocated by __dev_map_alloc_node(). As far as I and
syzbot tested, https://syzkaller.appspot.com/x/patch.diff?x=140dd206e00000
can avoid the problem, but I don't know whether this is right location to
assign it. Please check and fix.


  reply	other threads:[~2019-11-15  9:44 UTC|newest]

Thread overview: 40+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <00000000000056268e05737dcb95@google.com>
     [not found] ` <000000000000c5b63005737f290d@google.com>
2018-08-15 20:41   ` unregister_netdevice: waiting for DEV to become free (2) Dmitry Vyukov
2018-08-20  4:31 ` syzbot
2018-08-20 12:55   ` Julian Anastasov
2018-08-21  5:40     ` Cong Wang
2018-08-22  4:11       ` Julian Anastasov
2019-04-15 13:36     ` Tetsuo Handa
2019-04-15 15:35       ` David Ahern
2019-04-21 20:41         ` Stephen Suryaputra
2019-04-22 14:58           ` David Ahern
2019-04-22 16:04             ` Eric Dumazet
2019-04-22 16:09               ` Eric Dumazet
2019-04-16 14:00       ` Tetsuo Handa
2019-04-26 13:43         ` Tetsuo Handa
2019-04-27 17:16           ` David Ahern
2019-04-27 22:33             ` Tetsuo Handa
2019-04-27 23:52               ` Eric Dumazet
2019-04-28  4:22                 ` Tetsuo Handa
2019-04-28 15:04                   ` Eric Dumazet
2019-04-29 18:34                   ` David Ahern
2019-04-29 18:43                     ` David Ahern
2019-05-01 13:38                       ` Tetsuo Handa
2019-05-01 14:52                         ` David Ahern
2019-05-01 16:16                           ` Tetsuo Handa
2019-05-04 14:52                             ` [PATCH] ipv4: Delete uncached routes upon unregistration of loopback device Tetsuo Handa
2019-05-04 15:56                               ` Eric Dumazet
2019-05-04 17:09                                 ` Tetsuo Handa
2019-05-04 17:24                                   ` Eric Dumazet
2019-05-04 20:13                               ` Julian Anastasov
2019-11-28  9:56     ` unregister_netdevice: waiting for DEV to become free (2) Tetsuo Handa
2019-11-29  5:54       ` Lukas Bulwahn
2019-11-29  6:51       ` Jouni Högander
2019-12-05 10:00       ` Jouni Högander
2019-12-05 11:00         ` Tetsuo Handa
2019-12-16 11:12           ` Tetsuo Handa
2019-12-17  7:08             ` Jouni Högander
2019-10-11 10:14   ` Tetsuo Handa
2019-10-11 15:12     ` Alexei Starovoitov
2019-10-16 10:34       ` Toke Høiland-Jørgensen
2019-11-15  9:43         ` Tetsuo Handa [this message]
2019-11-21 11:36           ` Toke Høiland-Jørgensen

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=6f69f704-b51d-c3cb-02c6-8e6eb93f4194@i-love.sakura.ne.jp \
    --to=penguin-kernel@i-love.sakura.ne.jp \
    --cc=alexei.starovoitov@gmail.com \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=brouer@redhat.com \
    --cc=daniel@iogearbox.net \
    --cc=ddstreet@ieee.org \
    --cc=dvyukov@google.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=syzbot+30209ea299c09d8785c9@syzkaller.appspotmail.com \
    --cc=syzkaller-bugs@googlegroups.com \
    --cc=toke@redhat.com \
    --cc=yhs@fb.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).