On Fri 28-01-22 15:45:40, David Hildenbrand wrote:
> If register_memory() fails, we freed the memory block but already added
> the memory block to the group list, not good. Let's defer adding the
> block to the memory group to after registering the memory block device.
>
> We do handle it properly during unregister_memory(), but that's not
> called when the registration fails.
>
> Fixes: 028fc57a1c36 ("drivers/base/memory: introduce "memory groups" to logically group memory blocks")
> Cc: stable@xxxxxxxxxxxxxxx # v5.15+
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx>
> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Cc: Michal Hocko <mhocko@xxxxxxxx>
> Cc: Oscar Salvador <osalvador@xxxxxxx>
> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Thanks!
> ---
> drivers/base/memory.c | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/base/memory.c b/drivers/base/memory.c
> index 365cd4a7f239..60c38f9cf1a7 100644
> --- a/drivers/base/memory.c
> +++ b/drivers/base/memory.c
> @@ -663,14 +663,16 @@ static int init_memory_block(unsigned long block_id, unsigned long state,
> mem->nr_vmemmap_pages = nr_vmemmap_pages;
> INIT_LIST_HEAD(&mem->group_next);
>
> + ret = register_memory(mem);
> + if (ret)
> + return ret;
> +
> if (group) {
> mem->group = group;
> list_add(&mem->group_next, &group->memory_blocks);
> }
>
> - ret = register_memory(mem);
> -
> - return ret;
> + return 0;
> }
>
> static int add_memory_block(unsigned long base_section_nr)
> --
> 2.34.1
--
Michal Hocko
SUSE Labs
