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Date: Fri, 23 Jun 2017 23:50:25 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Don Zickus <dzickus@redhat.com>
cc: Kan Liang <kan.liang@intel.com>, linux-kernel@vger.kernel.org,
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Subject: Re: [PATCH V2] kernel/watchdog: fix spurious hard lockups
In-Reply-To: <20170623162907.l6inpxgztwwkeaoi@redhat.com>
Message-ID: <alpine.DEB.2.20.1706232348020.2234@nanos>
References: <20170621144118.5939-1-kan.liang@intel.com> <alpine.DEB.2.20.1706212235550.2152@nanos> <20170622154450.2lua7fdmigcixldw@redhat.com> <alpine.DEB.2.20.1706230952190.2647@nanos> <20170623162907.l6inpxgztwwkeaoi@redhat.com>
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On Fri, 23 Jun 2017, Don Zickus wrote:
> Hmm, all this work for a temp fix.  Kan, how much longer until the real fix
> of having perf count the right cycles?

Quite a while. The approach is wilfully breaking the user space ABI, which
is not going to happen.

And there is a simpler solution as well, as I said here:

    http://lkml.kernel.org/r/alpine.DEB.2.20.1706221730520.1885@nanos

Thanks,

	tglx