diff options
author | Hans Verkuil <hverkuil-cisco@xs4all.nl> | 2023-08-17 13:41:32 +0300 |
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committer | Hans Verkuil <hverkuil-cisco@xs4all.nl> | 2023-09-15 00:31:55 +0300 |
commit | 735de5caf79e06cc9fb96b1b4f4974674ae3e917 (patch) | |
tree | 991855114179912151c1391bcba1d2ed0da3fd9d /drivers/media/common/videobuf2 | |
parent | 41ebaa5e0eebea4c3bac96b72f9f8ae0d77c0bdb (diff) | |
download | linux-735de5caf79e06cc9fb96b1b4f4974674ae3e917.tar.xz |
media: vb2: frame_vector.c: replace WARN_ONCE with a comment
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>
Diffstat (limited to 'drivers/media/common/videobuf2')
-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 0f430ddc1f67..fd87747be9b1 100644 --- a/drivers/media/common/videobuf2/frame_vector.c +++ b/drivers/media/common/videobuf2/frame_vector.c @@ -31,6 +31,10 @@ * 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, bool write, @@ -59,8 +63,6 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames, bool write, 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; } |