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Date:   Tue, 18 Oct 2022 16:50:21 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Song Liu <songliubraving@meta.com>
Cc:     Christoph Hellwig <hch@lst.de>, Song Liu <song@kernel.org>,
        Linux-MM <linux-mm@kvack.org>,
        lkml <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        X86 ML <x86@kernel.org>, Peter Zijlstra <peterz@infradead.org>,
        Kernel Team <Kernel-team@fb.com>,
        "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>,
        "Hansen, Dave" <dave.hansen@intel.com>,
        "urezki@gmail.com" <urezki@gmail.com>
Subject: Re: [RFC v2 0/4] vmalloc_exec for modules and BPF programs
Message-ID: <20221018145021.GC20131@lst.de>
References: <20221007234315.2877365-1-song@kernel.org> <20221017072607.GA30977@lst.de> <E8A7DEAE-C1C6-4821-A3A3-FD4996414AFD@fb.com>
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On Mon, Oct 17, 2022 at 04:23:52PM +0000, Song Liu wrote:
> > Well, nothing explains what the method is to avoid having memory
> > that is mapped writable and executable at the same time, which really
> > could use some explanation here (and in the main patch as well).
> 
> Thanks for the feedback. I will add this. 
> 
> Does the code look good to you? I personally think patch 1, 2, 4 could
> ship with a little more work. 

I only took a quick look and I'm not sure how the W^X actually works.
Yes, it alls into the text poke helpers, but how do these work on
less than page sized allocations?