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Message-ID: <2ec21b71-bfdc-885f-827a-eca7b70f2728@linaro.org>
Date:   Thu, 21 Sep 2023 09:28:39 +0200
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Subject: Re: [PATCH v3 2/3] soc: qcom: rmtfs: Support discarding guard pages
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To:     Bjorn Andersson <quic_bjorande@quicinc.com>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>
Cc:     linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20230920-rmtfs-mem-guard-pages-v3-0-305b37219b78@quicinc.com>
 <20230920-rmtfs-mem-guard-pages-v3-2-305b37219b78@quicinc.com>
From:   Konrad Dybcio <konrad.dybcio@linaro.org>
In-Reply-To: <20230920-rmtfs-mem-guard-pages-v3-2-305b37219b78@quicinc.com>
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On 9/21/23 04:37, Bjorn Andersson wrote:
> In some configurations, the exact placement of the rmtfs shared memory
> region isn't so strict. The DeviceTree author can then choose to use the
> "size" property and rely on the OS for placement (in combination with
> "alloc-ranges", if desired).
> 
> But on some platforms the rmtfs memory region may not be allocated
> adjacent to regions allocated by other clients. Add support for
> discarding the first and last 4k block in the region, if
> qcom,use-guard-pages is specified in DeviceTree.
> 
> Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
> ---
I don't want to block this anymore, but I guess I should ask
the question whether it would be valuable to add a common
reserved-memory property for e.g. low-padding and high-padding

Have we seen cases of that outside rmtfs?

Konrad