Re: [PATCH v3 2/4] mm/memory_hotplug: Drop mem_blk check from unregister_mem_sect_under_nodes

From: Pasha Tatashin
Date: Thu Aug 16 2018 - 13:53:32 EST


On 18-08-15 16:42:17, Oscar Salvador wrote:
> From: Oscar Salvador <osalvador@xxxxxxx>
>
> Before calling to unregister_mem_sect_under_nodes(),
> remove_memory_section() already checks if we got a valid memory_block.
>
> No need to check that again in unregister_mem_sect_under_nodes().
>
> If more functions start using unregister_mem_sect_under_nodes() in the
> future, we can always place a WARN_ON to catch null mem_blk's so we can
> safely back off.
>
> For now, let us keep the check in remove_memory_section() since it is the
> only function that uses it.
>
> Signed-off-by: Oscar Salvador <osalvador@xxxxxxx>
> Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>

Reviewed-by: Pavel Tatashin <pavel.tatashin@xxxxxxxxxxxxx>

> ---
> drivers/base/node.c | 4 ----
> 1 file changed, 4 deletions(-)
>
> diff --git a/drivers/base/node.c b/drivers/base/node.c
> index 1ac4c36e13bb..dd3bdab230b2 100644
> --- a/drivers/base/node.c
> +++ b/drivers/base/node.c
> @@ -455,10 +455,6 @@ int unregister_mem_sect_under_nodes(struct memory_block *mem_blk,
> NODEMASK_ALLOC(nodemask_t, unlinked_nodes, GFP_KERNEL);
> unsigned long pfn, sect_start_pfn, sect_end_pfn;
>
> - if (!mem_blk) {
> - NODEMASK_FREE(unlinked_nodes);
> - return -EFAULT;
> - }
> if (!unlinked_nodes)
> return -ENOMEM;
> nodes_clear(*unlinked_nodes);
> --
> 2.13.6
>