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Message-ID: <20bdc913-57d2-abe9-d222-d77647281b43@redhat.com>
Date:   Mon, 16 Oct 2023 21:47:21 +0200
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Subject: Re: [PATCH v7 04/12] KVM: arm64: PMU: Don't define the sysreg reset()
 for PM{USERENR,CCFILTR}_EL0
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To:     Raghavendra Rao Ananta <rananta@google.com>,
        Oliver Upton <oliver.upton@linux.dev>,
        Marc Zyngier <maz@kernel.org>
Cc:     Alexandru Elisei <alexandru.elisei@arm.com>,
        James Morse <james.morse@arm.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Zenghui Yu <yuzenghui@huawei.com>,
        Shaoqin Huang <shahuang@redhat.com>,
        Jing Zhang <jingzhangos@google.com>,
        Reiji Watanabe <reijiw@google.com>,
        Colton Lewis <coltonlewis@google.com>,
        linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org
References: <20231009230858.3444834-1-rananta@google.com>
 <20231009230858.3444834-5-rananta@google.com>
From:   Eric Auger <eauger@redhat.com>
In-Reply-To: <20231009230858.3444834-5-rananta@google.com>
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Hi,

On 10/10/23 01:08, Raghavendra Rao Ananta wrote:
> From: Reiji Watanabe <reijiw@google.com>
> 
> The default reset function for PMU registers (defined by PMU_SYS_REG)
> now simply clears a specified register. Use the default one for
> PMUSERENR_EL0 and PMCCFILTR_EL0, as KVM currently clears those
> registers on vCPU reset (NOTE: All non-RES0 fields of those
> registers have UNKNOWN reset values, and the same fields of
> their AArch32 registers have 0 reset values).
> 
> No functional change intended.
> 
> Signed-off-by: Reiji Watanabe <reijiw@google.com>
> Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
> ---
>  arch/arm64/kvm/sys_regs.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
> index 3dbb7d276b0e..08af7824e9d8 100644
> --- a/arch/arm64/kvm/sys_regs.c
> +++ b/arch/arm64/kvm/sys_regs.c
> @@ -2180,7 +2180,7 @@ static const struct sys_reg_desc sys_reg_descs[] = {
>  	 * in 32bit mode. Here we choose to reset it as zero for consistency.
>  	 */
>  	{ PMU_SYS_REG(PMUSERENR_EL0), .access = access_pmuserenr,
> -	  .reset = reset_val, .reg = PMUSERENR_EL0, .val = 0 },
> +	  .reg = PMUSERENR_EL0, },
>  	{ PMU_SYS_REG(PMOVSSET_EL0),
>  	  .access = access_pmovs, .reg = PMOVSSET_EL0 },
>  
> @@ -2338,7 +2338,7 @@ static const struct sys_reg_desc sys_reg_descs[] = {
>  	 * in 32bit mode. Here we choose to reset it as zero for consistency.
>  	 */
>  	{ PMU_SYS_REG(PMCCFILTR_EL0), .access = access_pmu_evtyper,
> -	  .reset = reset_val, .reg = PMCCFILTR_EL0, .val = 0 },
> +	  .reg = PMCCFILTR_EL0, },
>  
>  	EL2_REG(VPIDR_EL2, access_rw, reset_unknown, 0),
>  	EL2_REG(VMPIDR_EL2, access_rw, reset_unknown, 0),

Reviewed-by: Eric Auger <eric.auger@redhat.com>

Thanks

Eric