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Date:   Wed, 28 Jun 2023 11:48:20 -0700
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Message-ID: <20230628184820.1375994-1-yuxiaozhang@google.com>
Subject: Re: [PATCH] pstore: ramoops: support pmsg size larger than kmalloc limitation
From:   Yuxiao Zhang <yuxiaozhang@google.com>
To:     Kees Cook <keescook@chromium.org>,
        "'Guilherme G . Piccoli'" <gpiccoli@igalia.com>
Cc:     Tony Luck <tony.luck@intel.com>,
        Greg KH <gregkh@linuxfoundation.org>,
        linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org,
        wak@google.com
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Thanks for the review Kees.

>And yes, Greg's questions are all good -- fixing syntax and adding size
details in the commit log would be appreciated.

Sure, will send another patch to address this.

Hi Guilherme, thanks for testing this patch.

>But when I tried to increase the record size in ramoops, I got this error: https://termbin.com/b12e

What record type are you testing? I should have mention that this patch is only for pmsg use case on ramoops (I mentioned it in the original thread but need to start a new one due to format issue).

>Also - Kees certainly knows that way better, but - are we 100% sure that
the region for pstore can be non-contiguous? For some reason, I always
thought this was a requirement

Right, that is why this patch only touches the pstore ram path, I am not sure how things will go if it is block device backed.

Thanks,
-Yuxiao Zhang