On Sat, Jul 04, 2020 at 02:26:07AM +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. > > Reviewed-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> > Reviewed-by: Pekka Enberg <penberg@xxxxxxxxxx> > Cc: Christoph Lameter <cl@xxxxxxxxx> > Cc: David Rientjes <rientjes@xxxxxxxxxx> > Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Signed-off-by: Long Li <lonuxli.64@xxxxxxxxx> > --- > > changes in v5: > -Change the check function name to kmalloc_fix_flags(), This name > may be more appropriate. > > changes in V4: > -Change the check function name to kmalloc_check_flags() > -Put the flags check into the kmalloc_check_flags() No. As I said: The point of not doing that was that this is unlikely(). With your change there is now a function call to check something that's (extremely) unlikely().
