Re: Interesting csd deadlock on ARC

From	Russell King - ARM Linux <linux@arm.linux.org.uk>
Newsgroups	linux.kernel
Subject	Re: Interesting csd deadlock on ARC
Date	2016-02-25 15:40 +0100
Message-ID	<r65fc-59a-17@gated-at.bofh.it> (permalink)
References	(1 earlier) <r5dHQ-Cg-3@gated-at.bofh.it> <r5hV8-3st-11@gated-at.bofh.it> <r5zIo-7K8-61@gated-at.bofh.it> <r64Mb-4WY-17@gated-at.bofh.it> <r655w-54N-13@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On Thu, Feb 25, 2016 at 07:53:39PM +0530, Vineet Gupta wrote:
> But then ARM CONFIG_SMP on UP hardware will still crap out because there
> is no way to send IPI to self. Same as the bug in above discussion. I'm
> surprised they way ARM guys worked around it.

We haven't worked around it - the code which provoked the oops that was
seen (in the cpufreq code) was changed not to call it, which has the
effect of making the problem "go away", at least for now.

We still have the problem that if it does get called on UP, it'll blow
up - and I don't see any point in complicating the code for something
that never happens right now.

-- 
RMK's Patch system: http://www.arm.linux.org.uk/developer/patches/
FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up
according to speedtest.net.

Thread

Re: Interesting csd deadlock on ARC Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-02-23 06:30 +0100
  Re: Interesting csd deadlock on ARC Peter Zijlstra <peterz@infradead.org> - 2016-02-23 11:00 +0100
    Re: Interesting csd deadlock on ARC Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-02-23 11:30 +0100
      Re: Interesting csd deadlock on ARC Peter Zijlstra <peterz@infradead.org> - 2016-02-23 11:50 +0100
        RE: Interesting csd deadlock on ARC Noam Camus <noamca@mellanox.com> - 2016-02-23 13:40 +0100
          Re: Interesting csd deadlock on ARC Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-02-24 05:50 +0100
    Re: Interesting csd deadlock on ARC Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-02-24 06:00 +0100
      Re: Interesting csd deadlock on ARC Peter Zijlstra <peterz@infradead.org> - 2016-02-25 15:10 +0100
        Re: Interesting csd deadlock on ARC Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-02-25 15:30 +0100
          Re: Interesting csd deadlock on ARC Russell King - ARM Linux <linux@arm.linux.org.uk> - 2016-02-25 15:40 +0100
            Re: Interesting csd deadlock on ARC Vineet Gupta <vgupta@synopsys.com> - 2016-02-25 17:00 +0100

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