On Thu, Nov 22, 2018 at 2:32 AM Christopher Lameter <cl@xxxxxxxxx> wrote: > > On Sun, 11 Nov 2018, Nicolas Boichat wrote: > > > SLAB_CACHE_DMA32 is only available after explicit kmem_cache_create calls, > > no default cache is created for kmalloc. Add a test in check_slab_flags > > for this. > > This does not define the dma32 kmalloc array. Is that intentional? Yes that's intentional, AFAICT there is no user, so there is no point creating the cache. (okay, I could find one, but it's probably broken: git grep GFP_DMA32 | grep k[a-z]*alloc drivers/media/platform/vivid/vivid-osd.c: dev->video_vbase = kzalloc(dev->video_buffer_size, GFP_KERNEL | GFP_DMA32); ). > In that > case you need to fail any request for GFP_DMA32 coming in via kmalloc. Well, we do check for these in check_slab_flags (aka GFP_SLAB_BUG_MASK before patch 1/3 of this series), so, with or without this patch, calls with GFP_DMA32 will end up failing in check_slab_flags.
