Re: [PATCH v4 07/38] mm: add mmap action for discontiguous kernel page mapping

["Lorenzo Stoakes (ARM)" <ljs@kernel.org>]

On Sun, Oct 04, 2026 at 10:11:18AM -0700, Suren Baghdasaryan wrote:
> On Sat, Oct 3, 2026 at 6:35 PM Lorenzo Stoakes (ARM) <ljs@kernel.org> wrote:

> > diff --git a/mm/memory.c b/mm/memory.c
> > index 448342883e9d..45b21bb04a18 100644
> > --- a/mm/memory.c
> > +++ b/mm/memory.c

> > +static void __map_kernel_pages_prepare(struct vm_area_desc *desc)
> > +{
> > +       if (vma_desc_test(desc, VMA_MIXEDMAP_BIT))
> > +               return;
> > +
> > +       VM_WARN_ON_ONCE(mmap_read_trylock(desc->mm));
>
> Sorry I missed this before and it is pre-existing code but is this a
> weird way of asserting that mmap_lock is write-locked? If so, why not
> just use mmap_assert_write_locked()?

Ah yeah, this weirdness is duplicated from the existing code. Will fix up on
resin!

--
Cheers, Lorenzo