On 16/11/2022 11:26, David Hildenbrand wrote:
FOLL_FORCE is really only for ptrace access. R/O pinning a page is supposed to fail if the VMA misses proper access permissions (no VM_READ).
Let's just remove FOLL_FORCE usage here; there would have to be a pretty good reason to allow arbitrary drivers to R/O pin pages in a PROT_NONE VMA. Most probably, FOLL_FORCE usage is just some legacy leftover.
I'm pretty sure about that as well, so:
Acked-by: Hans Verkuil hverkuil-cisco@xs4all.nl
Regards,
Hans
Cc: Andy Walls awalls@md.metrocast.net Cc: Mauro Carvalho Chehab mchehab@kernel.org Signed-off-by: David Hildenbrand david@redhat.com
drivers/media/pci/ivtv/ivtv-udma.c | 2 +- drivers/media/pci/ivtv/ivtv-yuv.c | 5 ++--- 2 files changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/media/pci/ivtv/ivtv-udma.c b/drivers/media/pci/ivtv/ivtv-udma.c index 210be8290f24..99b9f55ca829 100644 --- a/drivers/media/pci/ivtv/ivtv-udma.c +++ b/drivers/media/pci/ivtv/ivtv-udma.c @@ -115,7 +115,7 @@ int ivtv_udma_setup(struct ivtv *itv, unsigned long ivtv_dest_addr, /* Pin user pages for DMA Xfer */ err = pin_user_pages_unlocked(user_dma.uaddr, user_dma.page_count,
dma->map, FOLL_FORCE);
dma->map, 0);if (user_dma.page_count != err) { IVTV_DEBUG_WARN("failed to map user pages, returned %d instead of %d\n", diff --git a/drivers/media/pci/ivtv/ivtv-yuv.c b/drivers/media/pci/ivtv/ivtv-yuv.c index 4ba10c34a16a..582146f8d70d 100644 --- a/drivers/media/pci/ivtv/ivtv-yuv.c +++ b/drivers/media/pci/ivtv/ivtv-yuv.c @@ -63,12 +63,11 @@ static int ivtv_yuv_prep_user_dma(struct ivtv *itv, struct ivtv_user_dma *dma, /* Pin user pages for DMA Xfer */ y_pages = pin_user_pages_unlocked(y_dma.uaddr,
y_dma.page_count, &dma->map[0], FOLL_FORCE);
y_dma.page_count, &dma->map[0], 0);
uv_dma.page_count, &dma->map[y_pages],FOLL_FORCE);
uv_dma.page_count, &dma->map[y_pages], 0);if (y_pages != y_dma.page_count || uv_pages != uv_dma.page_count) {