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From: Peter Maydell <peter.maydell@linaro.org>
Date: Mon, 9 Mar 2015 22:31:19 +0900
Message-ID: <CAFEAcA_DqHx-sDMuhSr0-uQL20-uJzXXpBvr6YLUWmzMN2mL4w@mail.gmail.com>
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Subject: Re: [Qemu-devel] [PATCH 5/6] target-arm/kvm64: fix save/restore of
	SPSR regs
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To: Christoffer Dall <christoffer.dall@linaro.org>
Cc: kvm-devel <kvm@vger.kernel.org>, Marc Zyngier <marc.zyngier@arm.com>, QEMU Developers <qemu-devel@nongnu.org>, =?UTF-8?B?QWxleCBCZW5uw6ll?= <alex.bennee@linaro.org>, "kvmarm@lists.cs.columbia.edu" <kvmarm@lists.cs.columbia.edu>, arm-mail-list <linux-arm-kernel@lists.infradead.org>

On 9 March 2015 at 21:56, Christoffer Dall <christoffer.dall@linaro.org> wrote:
> this function, however, is not used only when migration, but should
> generally cover the case where you want to synchronize QEMU's state into
> KVM's state, right?  So while it may not be harmful in currently
> supported use cases, is there ever a situation where (is_a64(env) && el
> == 0) and env->spsr != banked_spsr[el], and where env->spsr is
> out-of-date?

If EL == 0 then you can't access any SPSR, so env->spsr is by
definition out of date.

-- PMM