From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: [PATCH] kvm: don't take vcpu mutex for obviously invalid vcpu
 ioctls
Date: Mon, 22 Sep 2014 21:13:08 -0300
Message-ID: <20140923001308.GA13962@amt.cnet>
References: <1411167805-2458-1-git-send-email-dmatlack@google.com>
 <20140922200812.GA9217@amt.cnet>
 <20140922225816.GD8347@google.com>
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Cc: Gleb Natapov <gleb@kernel.org>,
	Paolo Bonzini <pbonzini@redhat.com>, kvm@vger.kernel.org,
	linux-kernel@vger.kernel.org
To: David Matlack <dmatlack@google.com>
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On Mon, Sep 22, 2014 at 03:58:16PM -0700, David Matlack wrote:
> > Should not be executing vcpu ioctls without interrupt KVM_RUN in the
> > first place.
> 
> This patch is trying to be nice to code that isn't aware it's
> probing kvm file descriptors. We saw long hangs with some generic
> process inspection code that was probing all open file descriptors.
> There's no reason non-kvm ioctls should have to wait for the vcpu
> mutex to become available just to fail.

OK then, please add the usecase to the changelog.