Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Mon, 2 Mar 2020 14:32:42 +0000
From:   Ionela Voinescu <ionela.voinescu@arm.com>
To:     Marc Zyngier <maz@kernel.org>
Cc:     catalin.marinas@arm.com, will@kernel.org, mark.rutland@arm.com,
        suzuki.poulose@arm.com, sudeep.holla@arm.com, lukasz.luba@arm.com,
        valentin.schneider@arm.com, dietmar.eggemann@arm.com,
        rjw@rjwysocki.net, pkondeti@codeaurora.org, peterz@infradead.org,
        mingo@redhat.com, vincent.guittot@linaro.org,
        viresh.kumar@linaro.org, linux-arm-kernel@lists.infradead.org,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-pm@vger.kernel.org, James Morse <james.morse@arm.com>,
        Julien Thierry <julien.thierry.kdev@gmail.com>
Subject: Re: [PATCH v5 3/7] arm64/kvm: disable access to AMU registers from
 kvm guests
Message-ID: <20200302143242.GB15709@arm.com>
References: <20200226132947.29738-1-ionela.voinescu@arm.com>
 <20200226132947.29738-4-ionela.voinescu@arm.com>
 <46b89d0c9704e0a0fb7a4ac2a1fb5b7a@kernel.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <46b89d0c9704e0a0fb7a4ac2a1fb5b7a@kernel.org>
User-Agent: Mutt/1.9.4 (2018-02-28)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Hi Marc,

On Thursday 27 Feb 2020 at 19:58:32 (+0000), Marc Zyngier wrote:
[..]
> >  static bool trap_ptrauth(struct kvm_vcpu *vcpu,
> >  			 struct sys_reg_params *p,
> >  			 const struct sys_reg_desc *rd)
> > @@ -1078,8 +1092,10 @@ static u64 read_id_reg(const struct kvm_vcpu
> > *vcpu,
> >  			 (u32)r->CRn, (u32)r->CRm, (u32)r->Op2);
> >  	u64 val = raz ? 0 : read_sanitised_ftr_reg(id);
> > 
> > -	if (id == SYS_ID_AA64PFR0_EL1 && !vcpu_has_sve(vcpu)) {
> > -		val &= ~(0xfUL << ID_AA64PFR0_SVE_SHIFT);
> > +	if (id == SYS_ID_AA64PFR0_EL1) {
> > +		if (!vcpu_has_sve(vcpu))
> > +			val &= ~(0xfUL << ID_AA64PFR0_SVE_SHIFT);
> > +		val &= ~(0xfUL << ID_AA64PFR0_AMU_SHIFT);
> 
> This will definitely conflict with some of the ongoing rework I have[1].
> I'm happy to provide this as a stable branch for you to rebase on top,
> or use an arm64 provided branch to rebase my stoff on top.
> 
> Just let me know how you want to proceed.
> 

Sure, a stable branch with this would be great. I'll wait for a reply
from Catalin for [1/7] and I'll rebase on top of your provided branch
when it's clear whether other changes are needed to this set.

Much appreciated,
Ionela.

> Thanks,
> 
>         M.
> 
> [1] https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git/commit/?h=kvm-arm64/debug-fixes-5.6&id=454fb7398d3626328f7f771c07d21e894e4e1a3b
> -- 
> Jazz is not dead. It just smells funny...