From: Rainer Weikusat <rweikusat@mobileactivedefense•com>
To: Eric Dumazet <eric.dumazet@gmail•com>
Cc: Rainer Weikusat <rweikusat@mobileactivedefense•com>,
davem@davemloft•net, hannes@stressinduktion•org,
edumazet@google•com, dhowells@redhat•com, ying.xue@windriver•com,
"netdev\@vger.kernel.org" <netdev@vger•kernel.org>,
LKML <linux-kernel@vger•kernel.org>,
"stable\@vger.kernel.org" <stable@vger•kernel.org>,
Joseph Salisbury <joseph.salisbury@canonical•com>
Subject: Re: [V4.4-rc6 Regression] af_unix: Revert 'lock_interruptible' in stream receive code
Date: Sun, 07 Feb 2016 22:24:22 +0000 [thread overview]
Message-ID: <87io20upk9.fsf@doppelsaurus.mobileactivedefense.com> (raw)
In-Reply-To: <8737t4jr99.fsf@doppelsaurus.mobileactivedefense.com> (Rainer Weikusat's message of "Sun, 07 Feb 2016 18:43:14 +0000")
Rainer Weikusat <rw@doppelsaurus•mobileactivedefense.com> writes:
[...]
> The start uses that to record an error which might need to be
> reported, the return statement uses it to indicate that an error has
> occurred. Hence, some kind of in-between translation must occur. The
> mutex_lock_interruptible happened to do that but that was never it's
> intended purpose.
Additional information: The 'trick' of using recvmsg w/o a receive
buffer in order to retrieve control messages in fact wouldn't have
worked with the unix_stream_recvmsg prior to introduction of the
interruptible lock as that (judging from the git source) would have
triggered all the same issues,
- -EOPNOTSUP if a msg was available
- -EAGAIN if the code had to wait
- not receiving the creds if the -EAGAIN hadn't happened because
of the continue (that's the other patch)
IOW, that's a feature inadvertendly added by an otherwise useless code
change (mea culpa).
next prev parent reply other threads:[~2016-02-07 22:24 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-02-05 18:50 [V4.4-rc6 Regression] af_unix: Revert 'lock_interruptible' in stream receive code Joseph Salisbury
2016-02-05 19:59 ` Rainer Weikusat
2016-02-05 20:06 ` Joseph Salisbury
2016-02-05 21:18 ` Rainer Weikusat
2016-02-05 22:04 ` Rainer Weikusat
2016-02-05 21:44 ` Rainer Weikusat
2016-02-05 23:03 ` Eric Dumazet
2016-02-07 18:43 ` Rainer Weikusat
2016-02-07 20:39 ` Rainer Weikusat
2016-02-07 22:24 ` Rainer Weikusat [this message]
2016-02-08 3:35 ` Eric Dumazet
2016-02-05 22:30 ` [PATCH] af_unix: Don't set err in unix_stream_read_generic unless there was an error Rainer Weikusat
2016-02-07 19:20 ` Rainer Weikusat
2016-02-08 15:33 ` Rainer Weikusat
2016-02-08 18:05 ` Rainer Weikusat
2016-02-08 18:47 ` Rainer Weikusat
2016-02-16 17:51 ` David Miller
2016-02-17 0:24 ` Ben Hutchings
2016-02-17 1:07 ` David Miller
2016-02-08 18:33 ` Sergei Shtylyov
2016-02-11 21:31 ` Joseph Salisbury
2016-02-12 13:31 ` Rainer Weikusat
2016-02-13 0:18 ` Ben Hutchings
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=87io20upk9.fsf@doppelsaurus.mobileactivedefense.com \
--to=rweikusat@mobileactivedefense$(echo .)com \
--cc=davem@davemloft$(echo .)net \
--cc=dhowells@redhat$(echo .)com \
--cc=edumazet@google$(echo .)com \
--cc=eric.dumazet@gmail$(echo .)com \
--cc=hannes@stressinduktion$(echo .)org \
--cc=joseph.salisbury@canonical$(echo .)com \
--cc=linux-kernel@vger$(echo .)kernel.org \
--cc=netdev@vger$(echo .)kernel.org \
--cc=stable@vger$(echo .)kernel.org \
--cc=ying.xue@windriver$(echo .)com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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