[Intel-gfx] [PATCH 12/16] staging/comedi: mark as broken

2019-06-14 Thread Christoph Hellwig
comedi_buf.c abuse the DMA API in gravely broken ways, as it assumes it can call virt_to_page on the result, and the just remap it as uncached using vmap. Disable the driver until this API abuse has been fixed. Signed-off-by: Christoph Hellwig --- drivers/staging/comedi/Kconfig | 1 + 1 file ch

Re: [Intel-gfx] [PATCH 12/16] staging/comedi: mark as broken

2019-06-14 Thread Greg KH
On Fri, Jun 14, 2019 at 03:47:22PM +0200, Christoph Hellwig wrote: > comedi_buf.c abuse the DMA API in gravely broken ways, as it assumes it > can call virt_to_page on the result, and the just remap it as uncached > using vmap. Disable the driver until this API abuse has been fixed. > > Signed-of

Re: [Intel-gfx] [PATCH 12/16] staging/comedi: mark as broken

2019-06-14 Thread Christoph Hellwig
On Fri, Jun 14, 2019 at 04:02:39PM +0200, Greg KH wrote: > Perhaps a hint as to how we can fix this up? This is the first time > I've heard of the comedi code not handling dma properly. It can be fixed by: a) never calling virt_to_page (or vmalloc_to_page for that matter) on dma allocation

Re: [Intel-gfx] [PATCH 12/16] staging/comedi: mark as broken

2019-06-14 Thread Greg KH
On Fri, Jun 14, 2019 at 04:48:57PM +0200, Christoph Hellwig wrote: > On Fri, Jun 14, 2019 at 04:02:39PM +0200, Greg KH wrote: > > Perhaps a hint as to how we can fix this up? This is the first time > > I've heard of the comedi code not handling dma properly. > > It can be fixed by: > > a) never

Re: [Intel-gfx] [PATCH 12/16] staging/comedi: mark as broken

2019-06-14 Thread Christoph Hellwig
On Fri, Jun 14, 2019 at 05:30:32PM +0200, Greg KH wrote: > On Fri, Jun 14, 2019 at 04:48:57PM +0200, Christoph Hellwig wrote: > > On Fri, Jun 14, 2019 at 04:02:39PM +0200, Greg KH wrote: > > > Perhaps a hint as to how we can fix this up? This is the first time > > > I've heard of the comedi code n

Re: [Intel-gfx] [PATCH 12/16] staging/comedi: mark as broken

2019-06-18 Thread Ian Abbott
On 14/06/2019 16:34, Christoph Hellwig wrote: On Fri, Jun 14, 2019 at 05:30:32PM +0200, Greg KH wrote: On Fri, Jun 14, 2019 at 04:48:57PM +0200, Christoph Hellwig wrote: On Fri, Jun 14, 2019 at 04:02:39PM +0200, Greg KH wrote: Perhaps a hint as to how we can fix this up? This is the first tim