From: Miles Chen <miles.chen@mediatek.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: <linux-kernel@vger.kernel.org>, <wsd_upstream@mediatek.com>,
Miles Chen <miles.chen@mediatek.com>
Subject: [PATCH] dma-debug: add comment for failed to check map error
Date: Tue, 17 Jan 2017 11:04:49 +0800 [thread overview]
Message-ID: <1484622289-22085-1-git-send-email-miles.chen@mediatek.com> (raw)
Add comment for failed to check map error to help driver
developers.
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
---
lib/dma-debug.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/lib/dma-debug.c b/lib/dma-debug.c
index 8971370..60c57ec 100644
--- a/lib/dma-debug.c
+++ b/lib/dma-debug.c
@@ -1155,6 +1155,11 @@ static void check_unmap(struct dma_debug_entry *ref)
dir2name[ref->direction]);
}
+ /*
+ * Drivers should use dma_mapping_error() to check the returned
+ * addresses of dma_map_single() and dma_map_page().
+ * If not, print this warning message. See Documentation/DMA-API.txt.
+ */
if (entry->map_err_type == MAP_ERR_NOT_CHECKED) {
err_printk(ref->dev, entry,
"DMA-API: device driver failed to check map error"
--
1.9.1
reply other threads:[~2017-01-17 3:05 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1484622289-22085-1-git-send-email-miles.chen@mediatek.com \
--to=miles.chen@mediatek.com \
--cc=akpm@linux-foundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=wsd_upstream@mediatek.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).