Re: [PATCH 05/11] x86: remove HIGHMEM64G support

[Arnd Bergmann]

On Wed, Dec 4, 2024, at 17:37, H. Peter Anvin wrote:
> On December 4, 2024 5:29:17 AM PST, Brian Gerst <brgerst@xxxxxxxxx> wrote:
>>>
>>> Removing this also drops the need for PHYS_ADDR_T_64BIT and SWIOTLB.
>>> PAE mode is still required to get access to the 'NX' bit on Atom
>>> 'Pentium M' and 'Core Duo' CPUs.
>
> By the way, there are 64-bit machines which require swiotlb.

What I meant to write here was that CONFIG_X86_PAE no longer
needs to select PHYS_ADDR_T_64BIT and SWIOTLB. I ended up
splitting that change out to patch 06/11 with a better explanation,
so the sentence above is just wrong now and I've removed it
in my local copy now.

Obviously 64-bit kernels still generally need swiotlb.

       Arnd