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Date:   Thu, 13 Apr 2023 15:30:33 +0100
From:   Catalin Marinas <catalin.marinas@arm.com>
To:     Baoquan He <bhe@redhat.com>
Cc:     linux-kernel@vger.kernel.org, horms@kernel.org,
        thunder.leizhen@huawei.com, John.p.donnelly@oracle.com,
        will@kernel.org, kexec@lists.infradead.org,
        linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v5] arm64: kdump: simplify the reservation behaviour of
 crashkernel=,high
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On Thu, Apr 13, 2023 at 03:45:50PM +0800, Baoquan He wrote:
> I am OK with this version, or the version with min(SZ_4G,
> arm64_dma_phys_limit), or v4. Please help point out if I got your idea
> correctly. Thanks a lot.

I think we should stick to this patch. The disabling of the ZONE_DMA(32)
is fairly specialised and you are right that we should not introduce an
artificial 4GB crashkernel boundary on such systems. The slight
confusion may be that ,high triggers a search above 4GB where there's
not such boundary but this would match the documentation anyway.

-- 
Catalin