Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Tue, 17 Mar 2020 21:10:58 -0400
From:   Joel Fernandes <joel@joelfernandes.org>
To:     Tim Chen <tim.c.chen@linux.intel.com>
Cc:     Julien Desfossez <jdesfossez@digitalocean.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Vineeth Remanan Pillai <vpillai@digitalocean.com>,
        Aubrey Li <aubrey.intel@gmail.com>,
        Nishanth Aravamudan <naravamudan@digitalocean.com>,
        Ingo Molnar <mingo@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Paul Turner <pjt@google.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Linux List Kernel Mailing <linux-kernel@vger.kernel.org>,
        Dario Faggioli <dfaggioli@suse.com>,
        =?iso-8859-1?Q?Fr=E9d=E9ric?= Weisbecker <fweisbec@gmail.com>,
        Kees Cook <keescook@chromium.org>,
        Greg Kerr <kerrnel@google.com>, Phil Auld <pauld@redhat.com>,
        Aaron Lu <aaron.lwe@gmail.com>,
        Valentin Schneider <valentin.schneider@arm.com>,
        Mel Gorman <mgorman@techsingularity.net>,
        Pawan Gupta <pawan.kumar.gupta@linux.intel.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        "Luck, Tony" <tony.luck@intel.com>
Subject: Re: [RFC PATCH v4 00/19] Core scheduling v4
Message-ID: <20200318011058.GB111608@google.com>
References: <20200212230705.GA25315@sinkpad>
 <29d43466-1e18-6b42-d4d0-20ccde20ff07@linux.intel.com>
 <CAERHkruG4y8si9FrBp7cZNEdfP7EzxbmYwvdF2EvHLf=mU1mgg@mail.gmail.com>
 <CANaguZC40mDHfL1H_9AA7H8cyd028t9PQVRqQ3kB4ha8R7hhqg@mail.gmail.com>
 <CAERHkruPUrOzDjEp1FV3KY20p9CxLAVzKrZNe5QXsCFZdGskzA@mail.gmail.com>
 <CANaguZBj_x_2+9KwbHCQScsmraC_mHdQB6uRqMTYMmvhBYfv2Q@mail.gmail.com>
 <20200221232057.GA19671@sinkpad>
 <20200317005521.GA8244@google.com>
 <ee268494-c35e-422f-1aaf-baab12191c38@linux.intel.com>
 <1075ba53-91ed-2138-89b3-60fbfbd80b57@linux.intel.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <1075ba53-91ed-2138-89b3-60fbfbd80b57@linux.intel.com>
User-Agent: Mutt/1.12.2 (2019-09-21)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Hi Tim,

On Tue, Mar 17, 2020 at 01:18:45PM -0700, Tim Chen wrote:
[..] 
> Did you guys have a chance to try out v5 core scheduler?
> 
> > - Joel(ChromeOS) found a deadlock and crash on PREEMPT kernel in the
> >   coreshed idle balance logic
> 
> We did some patches to fix a few stability issues in v4.  I wonder
> if v5 still has the deadlock that you saw before?

I have not yet tested v5. I fixed the RCU-related deadlock in the scheduler
with this patch sent few days ago:
https://lore.kernel.org/patchwork/patch/1209561/

I'll rebase my tree on v5 soon.

Thanks!

 - Joel