Re: [PATCH 05/13] mm: prefer mm->def_vma_flags in mm logic

On Thu, Jul 02, 2026 at 08:10:22PM +0800, Lance Yang wrote:

On Mon, Jun 29, 2026 at 08:25:28PM +0100, Lorenzo Stoakes wrote:

quoted

Currently mm->def_flags (of type vm_flags_t) is union'd with
mm->def_vma_flags (of type vma_flags_t).

As part of the effort to convert vm_flags_t usage to vma_flags_t (in order
to no longer be arbitrarily limited to a system word size for VMA flags),
prefer mm->def_vma_flags to mm->def_flags throughout the mm logic.

No functional change intended.

Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
mm/debug.c |  2 +-
mm/mlock.c | 13 +++++++------
mm/mmap.c  | 11 ++++++-----
mm/vma.c   |  4 ++--
4 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/mm/debug.c b/mm/debug.c
index 497654b36f1a..f0a354a9496a 100644
--- a/mm/debug.c
+++ b/mm/debug.c

@@ -226,7 +226,7 @@ void dump_mm(const struct mm_struct *mm)

		mm->numa_next_scan, mm->numa_scan_offset, mm->numa_scan_seq,
#endif
		atomic_read(&mm->tlb_flush_pending),
-		mm->def_flags, &mm->def_flags
+		vma_flags_to_legacy(mm->def_vma_flags), &mm->def_vma_flags
	);

While at it, one thing for later: dump_mm() still assumes one-world VMA
flags. That works today since vma_flags_t is one word. Maybe worth a
BUILD_BUG_ON() here, before that stops being true?

Ah yeah that could actually be pretty straightforward, if you see
https://www.kernel.org/doc/Documentation/printk-formats.txt there is a bitmap
format that could be used.

Can do that on a respin!

Not a big deal though. Feel free to add:

Reviewed-by: Lance Yang <lance.yang@linux.dev>

quoted

}
EXPORT_SYMBOL(dump_mm);

[...]

Cheers, Lorenzo