From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH] af_unix: Revert 'lock_interruptible' in stream receive code Date: Thu, 17 Dec 2015 15:34:41 -0500 (EST) Message-ID: <20151217.153441.1336096182651045503.davem@davemloft.net> References: <877fke6tqi.fsf@doppelsaurus.mobileactivedefense.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org To: rweikusat@mobileactivedefense.com Return-path: In-Reply-To: <877fke6tqi.fsf@doppelsaurus.mobileactivedefense.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Rainer Weikusat Date: Wed, 16 Dec 2015 20:09:25 +0000 > With b3ca9b02b00704053a38bfe4c31dbbb9c13595d0, the AF_UNIX SOCK_STREAM > receive code was changed from using mutex_lock(&u->readlock) to > mutex_lock_interruptible(&u->readlock) to prevent signals from being > delayed for an indefinite time if a thread sleeping on the mutex > happened to be selected for handling the signal. But this was never a > problem with the stream receive code (as opposed to its datagram > counterpart) as that never went to sleep waiting for new messages with the > mutex held and thus, wouldn't cause secondary readers to block on the > mutex waiting for the sleeping primary reader. As the interruptible > locking makes the code more complicated in exchange for no benefit, > change it back to using mutex_lock. > > Signed-off-by: Rainer Weikusat Applied, thanks Rainer.