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Subject: Re: perf hw  in kexeced kernel broken in tip
From: Peter Zijlstra <peterz@infradead.org>
To: Vivek Goyal <vgoyal@redhat.com>
Cc: Don Zickus <dzickus@redhat.com>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
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Date: Wed, 08 Dec 2010 15:48:04 +0100
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On Wed, 2010-12-08 at 09:42 -0500, Vivek Goyal wrote:
> 
> Either driver itself can detect that device is in inconsistent state and
> reset it otherwise we also pass a command line parameter "reset_devices" to
> second kernel to explicitly tell kernel that devices might be in bad state,
> reset these during initialization. If we want to use these perf counters in
> kdump kernel, we shall have to do something similar.

Right, so I'm perfectly fine with leaving the kdump kernel broken for
now and if people really do need hardware events we can try and reset
the hardware when we find that reset_devices command line parameter.

Not sure how that interacts with these broken BIOSes, but its kdump so
its mostly broken by design anyway ;-)