Re: Regression after commit 19809c2da28a ("mm, vmalloc: use __GFP_HIGHMEM implicitly")

[Laura Abbott]

On 02/08/2018 10:18 AM, Matthew Wilcox wrote:
> On Thu, Feb 08, 2018 at 09:56:42AM -0800, Laura Abbott wrote:
> > > +++ b/drivers/media/v4l2-core/videobuf-dma-sg.c
> > > @@ -77,7 +77,7 @@ static struct scatterlist *videobuf_vmalloc_to_sg(unsigned char *virt,
> > >    		pg = vmalloc_to_page(virt);
> > >    		if (NULL == pg)
> > >    			goto err;
> > > -		BUG_ON(PageHighMem(pg));
> > > +		BUG_ON(page_to_pfn(pg) >= (1 << (32 - PAGE_SHIFT)));
> > >    		sg_set_page(&sglist[i], pg, PAGE_SIZE, 0);
> > >    	}
> > >    	return sglist;
> >
> > the vzalloc in this function needs to be switched to vmalloc32 if it
> > actually wants to guarantee 32-bit memory.
>
> Whoops, you got confused between the sglist allocation and the allocation
> of the pages which will be mapped ...

Ah yeah, clearly need more coffee this morning.