Re: [PATCH v3] mm, slab: Check GFP_SLAB_BUG_MASK before alloc_pages in kmalloc_order

From: Matthew Wilcox
Date: Wed Jul 01 2020 - 11:24:42 EST


On Wed, Jul 01, 2020 at 03:16:45PM +0000, Long Li wrote:
> kmalloc cannot allocate memory from HIGHMEM. Allocating large amounts
> of memory currently bypasses the check and will simply leak the memory
> when page_address() returns NULL. To fix this, factor the
> GFP_SLAB_BUG_MASK check out of slab & slub, and call it from
> kmalloc_order() as well. In order to make the code clear, the warning
> message is put in one place.
>
> Signed-off-by: Long Li <lonuxli.64@xxxxxxxxx>

Reviewed-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>