Re: [PATCH] mm/shmem: use invalidate_lock to fix hole-punch race

From: Gregory Price

Date: Fri Mar 27 2026 - 00:35:25 EST


On Thu, Mar 26, 2026 at 07:16:05PM +0000, Pedro Falcato wrote:
> On Thu, Mar 26, 2026 at 01:37:17PM -0500, Gregory Price wrote:
>
> _If_ there is indeed breakage here regarding tree rotations, I would suggest:
>
> diff --git a/mm/mmap.c b/mm/mmap.c
> index 5754d1c36462..7b4e39063d67 100644

fwiw this does not resolve the BUG() i'm observing.

I'm still trying to find a good reproducer that doesn't require
launching ~100s of VMs and ballooning them, but the condition here seems
extremely narrow.

~Gregory