Re: [PATCH] mm: add missing alloc_percpu() NULL check in hotplug init

[Mike Rapoport]

On Fri, Jul 17, 2026 at 01:29:38PM +0800, Hongfu Li wrote:
> From: Hongfu Li <lihongfu@xxxxxxxxxx>
> 
> No NULL check is done for alloc_percpu() when initializing per-CPU
> nodestats. Allocation failure leads to NULL pointer dereference
> during later memset.
> 
> Make function return int, check alloc_percpu() result and return
> -ENOMEM on error. The caller chain already propagates this error
> correctly.

I already applied a fix from Gregory:

https://patch.msgid.link/20260701221613.2818148-1-gourry@xxxxxxxxxx

It'll be unstreamed soon.
 
> Signed-off-by: Hongfu Li <lihongfu@xxxxxxxxxx>
> ---
>  include/linux/memory_hotplug.h |  2 +-
>  mm/memory_hotplug.c            |  3 ++-
>  mm/mm_init.c                   | 14 +++++++++++---
>  3 files changed, 14 insertions(+), 5 deletions(-)

-- 
Sincerely yours,
Mike.