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Date:   Mon, 8 Apr 2019 08:32:50 +0200 (CEST)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     "Leizhen (ThunderTown)" <thunder.leizhen@huawei.com>
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Subject: Re: [PATCH v4 0/6] normalize IOMMU dma mode boot options
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References: <20190407124147.13576-1-thunder.leizhen@huawei.com> <b20fd8a6-88ce-7d26-8eb0-ed9f095988a6@huawei.com> <5CAABD03.9000301@huawei.com>
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On Mon, 8 Apr 2019, Leizhen (ThunderTown) wrote:
> > 
> > This will break systems using boot options as now, and I think
> > this is unacceptable. If you want to do so, just introduce iommu.dma_mode
> > on top of those iommu boot options with dma mode boot options unchanged,
> > and iommu.dma_mode is for all archs but compatible with them.
> 
> I just changed the boot options name, but keep the function no change. I added
> all related maintainers/supporters in the "to=" list, maybe we can disuss this.

Changing the name _IS_ the problem. Think about unattended updates.

> Should I add some "obsoleted" warnings for old options and keep them for a while?

No, just keep the old options around for backwards compatibilty sake. We
just do not add new arch specific options in the future. New options need
to use the generic iommu.dma_mode name space.

Thanks,

	tglx