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[66.111.4.227]) by smtp.gmail.com with ESMTPSA id q32sm3859272qtf.36.2020.06.11.16.55.36 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 11 Jun 2020 16:55:37 -0700 (PDT) Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailauth.nyi.internal (Postfix) with ESMTP id 339CB27C0054; Thu, 11 Jun 2020 19:55:36 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute3.internal (MEProxy); Thu, 11 Jun 2020 19:55:36 -0400 X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduhedrudeitddgvdelucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhepfffhvffukfhfgggtuggjsehttdertddttddvnecuhfhrohhmpeeuohhquhhn ucfhvghnghcuoegsohhquhhnrdhfvghnghesghhmrghilhdrtghomheqnecuggftrfgrth htvghrnhepveeijedthfeijeefudehhedvveegudegteehgffgtddvuedtveegtedvvdef gedtnecuffhomhgrihhnpehkvghrnhgvlhdrohhrghenucfkphephedvrdduheehrdduud durdejudenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhm pegsohhquhhnodhmvghsmhhtphgruhhthhhpvghrshhonhgrlhhithihqdeiledvgeehtd eigedqudejjeekheehhedvqdgsohhquhhnrdhfvghngheppehgmhgrihhlrdgtohhmsehf ihigmhgvrdhnrghmvg X-ME-Proxy: Received: from localhost (unknown [52.155.111.71]) by mail.messagingengine.com (Postfix) with ESMTPA id 4AB2D3060FE7; Thu, 11 Jun 2020 19:55:27 -0400 (EDT) Date: Fri, 12 Jun 2020 07:55:26 +0800 From: Boqun Feng To: Waiman Long Cc: Peter Zijlstra , Dmitry Vyukov , syzbot , Alexey Dobriyan , Andrew Morton , allison@lohutok.net, areber@redhat.com, aubrey.li@linux.intel.com, Andrei Vagin , Bruce Fields , Christian Brauner , cyphar@cyphar.com, "Eric W. Biederman" , Greg Kroah-Hartman , guro@fb.com, Jeff Layton , Joel Fernandes , Kees Cook , linmiaohe@huawei.com, linux-fsdevel , LKML , Michal Hocko , Ingo Molnar , Oleg Nesterov , sargun@sargun.me, syzkaller-bugs , Thomas Gleixner , Al Viro Subject: Re: possible deadlock in send_sigio Message-ID: <20200611235526.GC94665@debian-boqun.qqnc3lrjykvubdpftowmye0fmh.lx.internal.cloudapp.net> References: <000000000000760d0705a270ad0c@google.com> <69818a6c-7025-8950-da4b-7fdc065d90d6@redhat.com> <88c172af-46df-116e-6f22-b77f98803dcb@redhat.com> <20200611142214.GI2531@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Hi Peter and Waiman, On Thu, Jun 11, 2020 at 12:09:59PM -0400, Waiman Long wrote: > On 6/11/20 10:22 AM, Peter Zijlstra wrote: > > On Thu, Jun 11, 2020 at 09:51:29AM -0400, Waiman Long wrote: > > > > > There was an old lockdep patch that I think may address the issue, but was > > > not merged at the time. I will need to dig it out and see if it can be > > > adapted to work in the current kernel. It may take some time. > > Boqun was working on that; I can't remember what happened, but ISTR it > > was shaping up nice. > > > Yes, I am talking about Boqun's patch. However, I think he had moved to > another company and so may not be able to actively work on that again. > I think you are talking about the rescursive read deadlock detection patchset: https://lore.kernel.org/lkml/20180411135110.9217-1-boqun.feng@gmail.com/ Let me have a good and send a new version based on today's master of tip tree. Regards, Boqun > Cheers, > Longman >