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Date:   Sun, 05 Jul 2020 13:00:10 +0100
Message-ID: <87r1tqdved.wl-maz@kernel.org>
From:   Marc Zyngier <maz@kernel.org>
To:     David Brazdil <dbrazdil@google.com>
Cc:     Will Deacon <will@kernel.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        James Morse <james.morse@arm.com>,
        Julien Thierry <julien.thierry.kdev@gmail.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, android-kvm@google.com,
        kernel-team@android.com
Subject: Re: [PATCH v4 08/15] arm64: kvm: Duplicate hyp/tlb.c for VHE/nVHE
In-Reply-To: <20200625131420.71444-9-dbrazdil@google.com>
References: <20200625131420.71444-1-dbrazdil@google.com>
        <20200625131420.71444-9-dbrazdil@google.com>
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On Thu, 25 Jun 2020 14:14:13 +0100,
David Brazdil <dbrazdil@google.com> wrote:
> 
> tlb.c contains code for flushing the TLB, with code shared between VHE/nVHE.
> Because common code is small, duplicate tlb.c and specialize each copy for
> VHE/nVHE.
> 
> Signed-off-by: David Brazdil <dbrazdil@google.com>
> ---
>  arch/arm64/kernel/image-vars.h      |  14 +--
>  arch/arm64/kvm/hyp/Makefile         |   2 +-
>  arch/arm64/kvm/hyp/nvhe/Makefile    |   2 +-
>  arch/arm64/kvm/hyp/{ => nvhe}/tlb.c |  94 +---------------
>  arch/arm64/kvm/hyp/vhe/Makefile     |   2 +-
>  arch/arm64/kvm/hyp/vhe/tlb.c        | 162 ++++++++++++++++++++++++++++
>  6 files changed, 178 insertions(+), 98 deletions(-)
>  rename arch/arm64/kvm/hyp/{ => nvhe}/tlb.c (62%)
>  create mode 100644 arch/arm64/kvm/hyp/vhe/tlb.c

[...]

> diff --git a/arch/arm64/kvm/hyp/tlb.c b/arch/arm64/kvm/hyp/nvhe/tlb.c
> similarity index 62%
> rename from arch/arm64/kvm/hyp/tlb.c
> rename to arch/arm64/kvm/hyp/nvhe/tlb.c
> index d063a576d511..9513ad41db9a 100644
> --- a/arch/arm64/kvm/hyp/tlb.c
> +++ b/arch/arm64/kvm/hyp/nvhe/tlb.c
> @@ -4,8 +4,6 @@
>   * Author: Marc Zyngier <marc.zyngier@arm.com>
>   */
>  
> -#include <linux/irqflags.h>
> -
>  #include <asm/kvm_hyp.h>
>  #include <asm/kvm_mmu.h>
>  #include <asm/tlbflush.h>
> @@ -16,52 +14,8 @@ struct tlb_inv_context {
>  	u64		sctlr;
>  };

nit: You seem to have overlooked that some of the tlb_inv_context
fields are now unused. I plan to squash the following patch in:

diff --git a/arch/arm64/kvm/hyp/nvhe/tlb.c b/arch/arm64/kvm/hyp/nvhe/tlb.c
index 6fe190bb930a..d4475f8340c4 100644
--- a/arch/arm64/kvm/hyp/nvhe/tlb.c
+++ b/arch/arm64/kvm/hyp/nvhe/tlb.c
@@ -9,9 +9,7 @@
 #include <asm/tlbflush.h>
 
 struct tlb_inv_context {
-	unsigned long	flags;
 	u64		tcr;
-	u64		sctlr;
 };
 
 static void __tlb_switch_to_guest(struct kvm *kvm, struct tlb_inv_context *cxt)


Otherwise, this looks good to me.

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.