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Subject: Re: [PATCH v2 1/3] powerpc/mm: Export flush_all_mm()
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Michael Ellerman <mpe@ellerman.id.au>, Frederic Barrat
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Date: Thu, 31 Aug 2017 07:00:17 +1000
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On Wed, 2017-08-30 at 23:17 +1000, Michael Ellerman wrote:
> It's not clear why it makes sense for these to be empty. Either for the
> general idea of the "flush_all_mm()" API, or for your intended use by
> CXL.

Indeed. On hash we don't have a way to flush a PID out of the TLB,
but you can flush the whole LPID.

Cheers,
Ben.