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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Sep 19, 2023 at 01:18:31PM +0100, Robin Murphy wrote: > > This is not a theoretical question - does any in-kernel code actually > > do that and expect it to work? I didn't notice any.. > > I was hoping to have to say I'd only seen it in unmerged (e.g. [1]) and > downstream code, but then I found drivers/net/ipa/ :( Aiiie, what is that doing? Mapping something into the dma-api owned domain!?! See this is why I think stronger invarients are a good idea, we can't police the entire kernel but we can make the entry points explode if someone is doing something WRONG. > All that said, I don't mind if you want to propose a separate patch to turn > certain external caller conditions into noisy warnings, but I wouldn't want > to tie it up with any other changes which would risk getting caught in the > crossfire if someone does then hit a newly-introduced warning and start > arguing to revert it. And I'm not going to do so in any of my patches since > as above I don't personally believe it's a valuable thing to do. Ok, that make sense Jason _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel