Messages in this thread | | | Date | Mon, 28 Sep 2020 13:46:55 +0200 | From | Paul Cercueil <> | Subject | Re: linux-next: build failure after merge of the drm tree |
| |
Le lun. 28 sept. 2020 à 13:34, Christoph Hellwig <hch@lst.de> a écrit : > On Mon, Sep 28, 2020 at 12:15:56PM +0200, Paul Cercueil wrote: >> Hi Christoph, >> >> Le lun. 28 sept. 2020 à 8:04, Christoph Hellwig <hch@lst.de> a >> écrit : >>> On Mon, Sep 28, 2020 at 01:54:05PM +1000, Stephen Rothwell wrote: >>>> Hi all, >>>> >>>> After merging the drm tree, today's linux-next build (x86_64 >>>> allmodconfig) >>>> failed like this: >>> >>> The driver needs to switch do dma_alloc_noncoherent + >>> dma_sync_single* >>> like the other drivers converted in the dma tree. Paul, let me >>> know if >>> you have any questions. >> >> I don't dma_alloc* anything, DRM core does. I use the >> DMA_ATTR_NON_CONSISTENT attr with dma_mmap_attrs(). Is there a >> replacement >> for that? > > dma_mmap_attrs can only be used on allocations from dma_mmap_attrs > with > the same attrs. As there is no allocation using > DMA_ATTR_NON_CONSISTENT > in the drm core, something looks very fishy here.
Is that a fact? I don't see why you couldn't change the cache settings after allocation. In practice it works just fine.
> Where does the allocation you try to mmap come from? All the > allocations > in drivers/gpu/drm/drm_gem_cma_helper.c seems to use dma_alloc_wc (aka > dma_allloc_attrs with the DMA_ATTR_WRITE_COMBINE flag).
It's the dma_alloc_wc.
-Paul
| |