linux-kernel - Re: [PATCH v2 01/12] x86/ioremap: Fix page aligned size calculation in __ioremap

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Message-ID: <10a4eb94-4764-717b-7c20-64a3d895b3d1@intel.com>
Date:   Mon, 14 Nov 2022 08:57:49 -0800
From:   Dave Hansen <dave.hansen@...el.com>
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Subject: Re: [PATCH v2 01/12] x86/ioremap: Fix page aligned size calculation
 in __ioremap_caller()

On 11/14/22 08:53, Michael Kelley (LINUX) wrote:
>> Because, first of all, that "Mappings have to be page-aligned" thing is
>> (now) doing more than page-aligning things.  Second, the moment you mask
>> out the metadata bits, the 'size' calculation gets harder.  Doing it in
>> two phases (page alignment followed by metadata bit masking) breaks up
>> the two logical operations.
>>
> Work for me.  Will do this in v3.

Kirill also made a good point about TDX: it isn't affected by this
because it always passes *real* (no metadata bits set) physical
addresses in here.  Could you double check that you don't want to do the
same for your code?