Re: [RFC PATCH 02/34] ARM: mm: make 2-level pgd_t a scalar
"David Hildenbrand (Arm)" <[email protected]>
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On 7/14/26 14:34, David Laight wrote: > On Mon, 13 Jul 2026 14:55:41 +0100 > Yeoreum Yun <[email protected]> wrote: > >> From: "David Hildenbrand (Arm)" <[email protected]> >> >> We don't want pgd_t to be an array, as it prohibits returning it from a >> function, like pgdp_get(). > > If you use a two element structure the compiler/ABI might be able to > return that from a function in two registers. > That might make the entire mess more readable ... The patch description states: " As an alternative, we could use the STRICT_MM_TYPECHECKS approach here as well, but using an u64 looks conceptually cleaner, even though pgd_val() gets a bit more involved. " Arnd replied on that in more detail. Maybe I should just go back to using bit shifts and handing endianess. -- Cheers, David