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Date: Tue, 3 Jan 2017 15:57:56 +0000
From: Mark Rutland <mark.rutland@arm.com>
To: Christopher Covington <cov@codeaurora.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>,
        Radim =?utf-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>,
        Christoffer Dall <christoffer.dall@linaro.org>,
        Marc Zyngier <marc.zyngier@arm.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>, kvm@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu,
        linux-kernel@vger.kernel.org, shankerd@codeaurora.org,
        timur@codeaurora.org
Subject: Re: [PATCH v2 4/5] arm64: Use __tlbi_dsb() macros in KVM code
Message-ID: <20170103155756.GB14183@leverpostej>
References: <20161229224335.13531-1-cov@codeaurora.org>
 <20161229224335.13531-4-cov@codeaurora.org>
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On Thu, Dec 29, 2016 at 05:43:34PM -0500, Christopher Covington wrote:
> Refactor the KVM code to use the newly introduced __tlbi_dsb macros, which
> will allow an errata workaround that repeats tlbi dsb sequences to only
> change one location. This is not intended to change the generated assembly
> and comparing before and after vmlinux objdump shows no functional changes.

> @@ -40,9 +41,7 @@ void __hyp_text __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa)
>  	 * complete (S1 + S2) walk based on the old Stage-2 mapping if
>  	 * the Stage-1 invalidation happened first.
>  	 */
> -	dsb(ish);

Looks like this got accidentally removed. AFAICT it is still necessary.

> -	asm volatile("tlbi vmalle1is" : : );
> -	dsb(ish);
> +	__tlbi_dsb(vmalle1is, ish);
>  	isb();

Thanks,
Mark.