From: Qian Cai <cai@lca.pw>
To: Dmitry Vyukov <dvyukov@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
Stephen Rothwell <sfr@canb.auug.org.au>,
Andrew Morton <akpm@linux-foundation.org>,
Peter Xu <peterx@redhat.com>, LKML <linux-kernel@vger.kernel.org>,
Linux-MM <linux-mm@kvack.org>, Jens Axboe <axboe@kernel.dk>,
Christoph Lameter <cl@linux.com>,
Johannes Weiner <hannes@cmpxchg.org>,
syzkaller <syzkaller@googlegroups.com>,
Dan Rue <dan.rue@linaro.org>
Subject: Re: [PATCH 0/2] mm: Two small fixes for recent syzbot reports
Date: Tue, 14 Apr 2020 07:59:16 -0400 [thread overview]
Message-ID: <04E78431-7B62-4FA1-8B1D-51DF7648D9C5@lca.pw> (raw)
In-Reply-To: <CACT4Y+ZE1XhYpTsjP1J1PyUsEHYKvchww71aHb7UnSk5=4xUrw@mail.gmail.com>
> On Apr 14, 2020, at 7:13 AM, Dmitry Vyukov <dvyukov@google.com> wrote:
>
> How do these use-after-free's and locking bugs get past the
> unit-testing systems (which syzbot is not) and remain unnoticed for so
> long?...
> syzbot uses the dumbest VMs (GCE), so everything it triggers during
> boot should be triggerable pretty much everywhere.
There are many reasons that any early testing would not be able to catch ALL the syzbot blockers.
The Kconfigs are different. For example, I don’t have openvswitch enabled, so would miss that ovs rcu-list lockdep warning. Same for that use-after-free in net/bluetooth and a warning in sound subsystem.
But, notifying Linux-next ML is a good start, so at least we could ask Paul or Steve to pull out the commit which enabling rcu-list debugging by default with PROVE_RCU.
I learned through that restricted kconfig to some degree of minimal could save a lot of troubles late on especially those options that I have no way to exercise like net/bluetooth and sound currently. It is going to be extra works though because those default options in Linux-next or even defconfigs are not always pleasant and would want to enable something I don’t need if not given human intervention.
next prev parent reply other threads:[~2020-04-14 11:59 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-08 1:40 [PATCH 0/2] mm: Two small fixes for recent syzbot reports Peter Xu
2020-04-08 1:40 ` [PATCH 1/2] mm/mempolicy: Allow lookup_node() to handle fatal signal Peter Xu
2020-04-08 10:21 ` Michal Hocko
2020-04-08 14:20 ` Peter Xu
2020-04-08 14:30 ` Michal Hocko
2020-04-08 15:24 ` Peter Xu
2020-04-08 15:26 ` Michal Hocko
2020-04-09 7:02 ` Michal Hocko
2020-04-09 12:52 ` Peter Xu
2020-04-09 13:00 ` Peter Xu
2020-04-09 13:53 ` Michal Hocko
2020-04-09 16:42 ` Linus Torvalds
2020-04-14 11:04 ` Michal Hocko
2020-04-14 13:49 ` Peter Xu
2020-04-14 14:18 ` Michal Hocko
2020-04-20 12:47 ` Michal Hocko
2020-04-20 17:31 ` Linus Torvalds
2020-04-21 7:09 ` Michal Hocko
2020-04-08 1:40 ` [PATCH 2/2] mm/gup: Mark lock taken only after a successful retake Peter Xu
2020-04-09 0:47 ` [PATCH 0/2] mm: Two small fixes for recent syzbot reports Andrew Morton
2020-04-09 11:49 ` Matthew Wilcox
2020-04-09 13:00 ` Dmitry Vyukov
2020-04-09 18:16 ` Andrew Morton
2020-04-09 18:53 ` Linus Torvalds
2020-04-09 19:12 ` Andrew Morton
2020-04-09 19:46 ` Linus Torvalds
2020-04-09 19:56 ` Matthew Wilcox
2020-04-09 19:58 ` Linus Torvalds
2020-04-09 20:27 ` Eric Biggers
2020-04-09 20:34 ` Linus Torvalds
2020-04-09 23:34 ` Stephen Rothwell
2020-04-10 1:11 ` Theodore Y. Ts'o
2020-04-09 12:55 ` Dmitry Vyukov
2020-04-09 16:32 ` Linus Torvalds
2020-04-09 16:58 ` Qian Cai
2020-04-09 17:05 ` Linus Torvalds
2020-04-09 17:58 ` Qian Cai
2020-04-09 18:06 ` Linus Torvalds
2020-04-09 21:14 ` Qian Cai
2020-04-10 13:12 ` Tetsuo Handa
2020-04-10 14:26 ` Qian Cai
2020-04-10 17:26 ` Andrew Morton
2020-04-10 19:46 ` Qian Cai
2020-04-09 23:29 ` Stephen Rothwell
2020-04-13 22:06 ` Qian Cai
2020-04-13 23:05 ` Jens Axboe
2020-04-14 11:12 ` Dmitry Vyukov
2020-04-14 11:59 ` Qian Cai [this message]
2020-04-14 12:05 ` Dmitry Vyukov
2020-04-14 19:28 ` Dan Rue
2020-04-15 11:09 ` Dmitry Vyukov
2020-04-15 16:23 ` Dan Rue
2020-04-16 0:34 ` Stephen Rothwell
2020-05-11 15:29 ` Dmitry Vyukov
[not found] <20200414040717.22040-1-hdanton@sina.com>
2020-04-14 4:31 ` Jens Axboe
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