From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH 3/3] x86: context_tracking: avoid irq_save/irq_restore on
 kernel entry and exit
Date: Wed, 28 Oct 2015 15:51:34 +0100
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Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	kvm list <kvm@vger.kernel.org>,
	Andy Lutomirski <luto@kernel.org>,
	Frederic Weisbecker <fweisbec@gmail.com>,
	Rik van Riel <riel@redhat.com>,
	Paul McKenney <paulmck@linux.vnet.ibm.com>
To: Andy Lutomirski <luto@amacapital.net>
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On 28/10/2015 06:22, Andy Lutomirski wrote:
>> > called by guest_enter and guest_exit.
>> >
>> > Use the previously introduced __context_tracking_entry and
>> > __context_tracking_exit.
> x86 isn't ready for this yet.  We could do a quick-and-dirty fix with
> explicit IRQs-on-and-off much protected by the static key, or we could
> just wait until I finish the syscall cleanup.  I favor the latter, but
> you're all welcome to do the former and I'll review it.

Or we could just do save/restore for the only call that doesn't ensure
that interrupts are disabled (syscall_trace_phase1 or whatever it's called).

But two days from the merge window, I also favor waiting until 4.5.

Paolo