Re: [PATCH v2 1/3] mm/memory-failure: report MF_MSG_KERNEL for reserved pages

Miaohe Lin
2026-04-07T02:56:49Z

On 2026/3/31 19:00, Breno Leitao wrote:
> When get_hwpoison_page() returns a negative value, distinguish
> reserved pages from other failure cases by reporting MF_MSG_KERNEL
> instead of MF_MSG_GET_HWPOISON. Reserved pages belong to the kernel
> and should be classified accordingly for proper handling by the
> panic_on_unrecoverable_memory_failure mechanism.
>
> Signed-off-by: Breno Leitao <leitao@debian.org>
> ---
> mm/memory-failure.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/mm/memory-failure.c b/mm/memory-failure.c
> index ee42d4361309..6ff80e01b91a 100644
> --- a/mm/memory-failure.c
> +++ b/mm/memory-failure.c
> @@ -2432,7 +2432,11 @@ int memory_failure(unsigned long pfn, int flags)
> }
> goto unlock_mutex;
> } else if (res < 0) {
> - res = action_result(pfn, MF_MSG_GET_HWPOISON, MF_IGNORED);
> + if (PageReserved(p))
> + res = action_result(pfn, MF_MSG_KERNEL, MF_IGNORED);

Is it safe or common to check page flags without holding extra refcnt?

Thanks.
.