From: Atsushi Nemoto <atsushi.nemoto@sord.co.jp>
To: Thor Thayer <thor.thayer@linux.intel.com>, <netdev@vger.kernel.org>
Cc: Dalon L Westergreen <dalon.westergreen@linux.intel.com>,
Tomonori Sakita <tomonori.sakita@sord.co.jp>
Subject: [PATCH v2] net: altera_tse: fix msgdma_tx_completion on non-zero fill_level case
Date: Fri, 25 Jan 2019 11:02:22 +0900 [thread overview]
Message-ID: <20190125.110222.956948485194493083.atsushi.nemoto@sord.co.jp> (raw)
From: Tomonori Sakita <tomonori.sakita@sord.co.jp>
If fill_level was not zero and status was not BUSY,
result of "tx_prod - tx_cons - inuse" might be zero.
Subtracting 1 unconditionally results invalid negative return value
on this case.
Make sure not to return an negative value.
Signed-off-by: Tomonori Sakita <tomonori.sakita@sord.co.jp>
Signed-off-by: Atsushi Nemoto <atsushi.nemoto@sord.co.jp>
Reviewed-by: Dalon L Westergreen <dalon.westergreen@linux.intel.com>
---
Changes in v2:
Use max_t instead of just removing the "- 1".
drivers/net/ethernet/altera/altera_msgdma.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/altera/altera_msgdma.c b/drivers/net/ethernet/altera/altera_msgdma.c
index 0fb986b..0ae723f 100644
--- a/drivers/net/ethernet/altera/altera_msgdma.c
+++ b/drivers/net/ethernet/altera/altera_msgdma.c
@@ -145,7 +145,8 @@ u32 msgdma_tx_completions(struct altera_tse_private *priv)
& 0xffff;
if (inuse) { /* Tx FIFO is not empty */
- ready = priv->tx_prod - priv->tx_cons - inuse - 1;
+ ready = max_t(int,
+ priv->tx_prod - priv->tx_cons - inuse - 1, 0);
} else {
/* Check for buffered last packet */
status = csrrd32(priv->tx_dma_csr, msgdma_csroffs(status));
--
2.1.4
next reply other threads:[~2019-01-25 2:03 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-25 2:02 Atsushi Nemoto [this message]
2019-01-25 15:03 ` [PATCH v2] net: altera_tse: fix msgdma_tx_completion on non-zero fill_level case Thor Thayer
2019-01-27 18:41 ` David Miller
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=20190125.110222.956948485194493083.atsushi.nemoto@sord.co.jp \
--to=atsushi.nemoto@sord.co.jp \
--cc=dalon.westergreen@linux.intel.com \
--cc=netdev@vger.kernel.org \
--cc=thor.thayer@linux.intel.com \
--cc=tomonori.sakita@sord.co.jp \
/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).