diff options
| author | Hans Verkuil | 2023-08-17 12:41:32 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman | 2023-10-06 14:56:56 +0200 |
| commit | e9f05ae6f63624fa95afdd7797610ec22d788d99 (patch) | |
| tree | be665064f3c9f8e10ce1a36e142ca0d79c7fdd16 /drivers/media | |
| parent | 28c36932492295eae9ce1ae4fe177cb344fc1e1c (diff) | |
media: vb2: frame_vector.c: replace WARN_ONCE with a comment
[ Upstream commit 735de5caf79e06cc9fb96b1b4f4974674ae3e917 ]
The WARN_ONCE was issued also in cases that had nothing to do with VM_IO
(e.g. if the start address was just a random value and uaccess fails with
-EFAULT).
There are no reports of WARN_ONCE being issued for actual VM_IO cases, so
just drop it and instead add a note to the comment before the function.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reported-by: Yikebaer Aizezi <yikebaer61@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/media')
| -rw-r--r-- | drivers/media/common/videobuf2/frame_vector.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/media/common/videobuf2/frame_vector.c b/drivers/media/common/videobuf2/frame_vector.c index 144027035892..07ebe4424df3 100644 --- a/drivers/media/common/videobuf2/frame_vector.c +++ b/drivers/media/common/videobuf2/frame_vector.c @@ -30,6 +30,10 @@ * different type underlying the specified range of virtual addresses. * When the function isn't able to map a single page, it returns error. * + * Note that get_vaddr_frames() cannot follow VM_IO mappings. It used + * to be able to do that, but that could (racily) return non-refcounted + * pfns. + * * This function takes care of grabbing mmap_lock as necessary. */ int get_vaddr_frames(unsigned long start, unsigned int nr_frames, @@ -55,8 +59,6 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames, if (likely(ret > 0)) return ret; - /* This used to (racily) return non-refcounted pfns. Let people know */ - WARN_ONCE(1, "get_vaddr_frames() cannot follow VM_IO mapping"); vec->nr_frames = 0; return ret ? ret : -EFAULT; } |