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Message-ID: <de8e450f-596f-bf99-d18a-ee771f9f2127@gmail.com>
Date:   Tue, 29 Mar 2022 20:37:01 -0700
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Subject: Re: [PATCH 1/2] arm64: mm: Do not defer reserve_crashkernel() if only
 ZONE_DMA32
Content-Language: en-US
To:     Kefeng Wang <wangkefeng.wang@huawei.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Cc:     Vijay Balakrishna <vijayb@linux.microsoft.com>,
        Pasha Tatashin <pasha.tatashin@soleen.com>
References: <20220325055315.25671-1-wangkefeng.wang@huawei.com>
From:   Florian Fainelli <f.fainelli@gmail.com>
In-Reply-To: <20220325055315.25671-1-wangkefeng.wang@huawei.com>
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On 3/24/2022 10:53 PM, Kefeng Wang wrote:
> The kernel could be benifit due to BLOCK_MAPPINGS, see commit
> 031495635b46 ("arm64: Do not defer reserve_crashkernel() for
> platforms with no DMA memory zones"), if there is only with
> ZONE_DMA32, we could set arm64_dma_phys_limit to max_zone_phys(32)
> earlier in arm64_memblock_init(), then we will benifit too.
> 
> Cc: Vijay Balakrishna <vijayb@linux.microsoft.com>
> Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
> Cc: Will Deacon <will@kernel.org>
> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> ---
>   arch/arm64/mm/init.c | 18 ++++++++++--------
>   arch/arm64/mm/mmu.c  |  6 ++----
>   2 files changed, 12 insertions(+), 12 deletions(-)
> 
> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
> index 8ac25f19084e..9dded8779d72 100644
> --- a/arch/arm64/mm/init.c
> +++ b/arch/arm64/mm/init.c
> @@ -157,14 +157,14 @@ static phys_addr_t __init max_zone_phys(unsigned int zone_bits)
>   	return min(zone_mask, memblock_end_of_DRAM() - 1) + 1;
>   }
>   
> +phys_addr_t __ro_after_init dma32_phys_limit;

This variable should still be scoped to this file, it is not used 
outside of arch/arm64/mm/init.c.
-- 
Florian