From: Linus Torvalds <torvalds@linux-foundation.org>
To: Jens Axboe <axboe@kernel.dk>
Cc: Eric Biggers <ebiggers3@gmail.com>,
Eryu Guan <guaneryu@gmail.com>,
Fengguang Wu <fengguang.wu@intel.com>,
Lukas Czerner <lczerner@redhat.com>, Jan Kara <jack@suse.cz>,
"Darrick J. Wong" <darrick.wong@oracle.com>,
Jeff Moyer <jmoyer@redhat.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: [btrfs] WARNING: CPU: 0 PID: 6379 at fs/direct-io.c:293 dio_complete+0x1d4/0x220
Date: Mon, 13 Nov 2017 11:21:50 -0800 [thread overview]
Message-ID: <CA+55aFxv4jVzoa_NpYOq=+TVpBvbSmJq++dPW5nmWNdxUEc-8Q@mail.gmail.com> (raw)
In-Reply-To: <ff823a95-3dff-0f2b-13ab-aab9bed7b0d3@kernel.dk>
On Mon, Nov 13, 2017 at 11:16 AM, Jens Axboe <axboe@kernel.dk> wrote:
>
> I would tend to agree with you, it's annoying to dump a full stack trace
> for an expected (even for a rare situation) condition. But it's not the
> first one, there's also one in XFS that always triggers for test runs. I
> complained about that one in the past.
Yeah, we should always consider a WARN_ON() that is triggerable from
user space to be a kernel bug.
If it's a "cannot happen", then the bug should be fixed.
If it's a "can happen, but I want to see the trace", then you just got
the trace and you're done, and the WARN_ON() should be removed.
It could possibly be replaced with a "pr_warn()" or something, so that
it still shows up as a "the user did something dodgy", but honestly,
even that is questionable. We do that for things like "we just removed
support for this, we want to see if somebody is using it"
So in no case is "let's just keep things as is" the right answer.
Linus
next prev parent reply other threads:[~2017-11-13 19:21 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CA+55aFxSJGeN=2X-uX-on1Uq2Nb8+v1aiMDz5H1+tKW_N5Q+6g@mail.gmail.com>
[not found] ` <20171029225155.qcum5i75awrt5tzm@wfg-t540p.sh.intel.com>
2017-10-30 7:20 ` [btrfs] WARNING: CPU: 0 PID: 6379 at fs/direct-io.c:293 dio_complete+0x1d4/0x220 Fengguang Wu
2017-10-30 7:44 ` Eryu Guan
2017-10-31 0:10 ` Fengguang Wu
2017-10-31 6:54 ` Eryu Guan
2017-10-31 7:10 ` Fengguang Wu
2017-11-06 1:13 ` Eric Biggers
2017-11-13 19:13 ` Eric Biggers
2017-11-13 19:16 ` Jens Axboe
2017-11-13 19:21 ` Linus Torvalds [this message]
2017-11-13 21:56 ` Darrick J. Wong
2017-11-13 22:01 ` Linus Torvalds
2017-11-14 17:17 ` Theodore Ts'o
2017-10-31 15:13 ` Filipe Manana
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='CA+55aFxv4jVzoa_NpYOq=+TVpBvbSmJq++dPW5nmWNdxUEc-8Q@mail.gmail.com' \
--to=torvalds@linux-foundation.org \
--cc=axboe@kernel.dk \
--cc=darrick.wong@oracle.com \
--cc=ebiggers3@gmail.com \
--cc=fengguang.wu@intel.com \
--cc=guaneryu@gmail.com \
--cc=jack@suse.cz \
--cc=jmoyer@redhat.com \
--cc=lczerner@redhat.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
/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).