Re: [PATCH v7 2/6] mm/vmalloc: fix vrealloc() grow-in-place check

[Alice Ryhl]

On Tue, Mar 24, 2026 at 03:30:27PM +0530, Shivam Kalra via B4 Relay wrote:
> From: Shivam Kalra <shivamkalra98@xxxxxxxxxxx>
> 
> Fix the grow-in-place check in vrealloc() to compare the requested size
> against the actual physical page count (vm->nr_pages) rather than the
> virtual area size (alloced_size, derived from get_vm_area_size()).
> 
> The virtual reservation size (get_vm_area_size()) does not decrease when
> pages are freed during a shrink operation. Consequently, without this fix,
> a subsequent grow-in-place operation after a shrink would incorrectly
> succeed and attempt to access freed pages. Correcting this check is a
> prerequisite for the upcoming vrealloc() shrink functionality.
> 
> Signed-off-by: Shivam Kalra <shivamkalra98@xxxxxxxxxxx>

This commit is titled 'fix', but is it actually a fix for a bug that
exists today? Or is it just a refactor to support the follow-up
shrinking logic?

Alice