Re: [PATCH] mm/vmalloc: clarify why vmap_range_noflush() might sleep

[Brendan Jackman]

Hi Anshuman, thanks a lot for taking a look.

On Mon Dec 8, 2025 at 6:41 AM UTC, Anshuman Khandual wrote:
> Please add <asm-generic/pgalloc.h> in mm/vmalloc.c - otherwise it does not
> get built as GFP_PGTABLE_KERNEL is not available. But otherwise LGTM.

Oh, but that's not correct, IIUC we shouldn't directly be including
asm-generic headers from here.

So while in principle GFP_PGTABLE_KERNEL is a sensible common
demoninator here, it doesn't actually exist at all everywhere, e.g. it
doesn't look like m68k defines it for Motorola. 

So maybe the best way here is a really vague:

/* 
 * Different archs allocate pagetables in different ways, assume
 * GFP_KERNEL as a common denominator.
 */
might_alloc(GFP_KERNEL)

... a bit yucky but I think still useful.

Any thoughts?