Hi Wei,
On Wed, Mar 12, 2025 at 01:07:27PM +0000, Wei Yang wrote:
> Commit 61167ad5fecd ("mm: pass nid to reserve_bootmem_region()") introduce
> a way to set nid to all reserved region.
>
> But there is a corner case it will leave some region with invalid nid.
> When memblock_set_node() doubles the array of memblock.reserved, it may
> lead to a new reserved region before current position. The new region
> will be left with an invalid node id.
>
> Repeat the process when detecting it.
>
> Fixes: 61167ad5fecd ("mm: pass nid to reserve_bootmem_region()")
> Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxx>
> CC: Mike Rapoport <rppt@xxxxxxxxxx>
> CC: Yajun Deng <yajun.deng@xxxxxxxxx>
> CC: <stable@xxxxxxxxxxxxxxx>
> ---
> mm/memblock.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/mm/memblock.c b/mm/memblock.c
> index 85442f1b7f14..302dd7bc622d 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -2184,7 +2184,10 @@ static void __init memmap_init_reserved_pages(void)
> * set nid on all reserved pages and also treat struct
> * pages for the NOMAP regions as PageReserved
> */
> +repeat:
> for_each_mem_region(region) {
> + unsigned long max = memblock.reserved.max;
> +
> nid = memblock_get_region_node(region);
> start = region->base;
> end = start + region->size;
> @@ -2193,6 +2196,15 @@ static void __init memmap_init_reserved_pages(void)
> reserve_bootmem_region(start, end, nid);
>
> memblock_set_node(start, region->size, &memblock.reserved, nid);
> +
> + /*
> + * 'max' is changed means memblock.reserved has been doubled
> + * its array, which may result a new reserved region before
> + * current 'start'. Now we should repeat the procedure to set
> + * its node id.
> + */
> + if (max != memblock.reserved.max)
> + goto repeat;
This check can be moved outside the loop, can't it?
> }
>
> /*
> --
> 2.34.1
>
--
Sincerely yours,
Mike.
