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Subject: Re: [PATCH 2/5] Protectable Memory Allocator
To: Christoph Hellwig <hch@infradead.org>,
        Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
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References: <20170605192216.21596-1-igor.stoppa@huawei.com>
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 <201706060444.v564iWds024768@www262.sakura.ne.jp>
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From: Igor Stoppa <igor.stoppa@huawei.com>
Message-ID: <214229a9-6e64-7351-1609-79c83d75d8c9@huawei.com>
Date: Tue, 6 Jun 2017 14:34:04 +0300
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On 06/06/17 09:25, Christoph Hellwig wrote:
> On Tue, Jun 06, 2017 at 01:44:32PM +0900, Tetsuo Handa wrote:

[..]

>> As far as I know, not all CONFIG_MMU=y architectures provide
>> set_memory_ro()/set_memory_rw(). You need to provide fallback for
>> architectures which do not provide set_memory_ro()/set_memory_rw()
>> or kernels built with CONFIG_MMU=n.
> 
> I think we'll just need to generalize CONFIG_STRICT_MODULE_RWX and/or
> ARCH_HAS_STRICT_MODULE_RWX so there is a symbol to key this off.

Would STRICT_KERNEL_RWX work? It's already present.
If both kernel text and rodata can be protected, so can pmalloc data.

---
igor