Linux RDMA and InfiniBand development
 help / color / mirror / Atom feed
From: Xiao Yang <yangx.jy@fujitsu.com>
To: <linux-rdma@vger.kernel.org>
Cc: <rpearsonhpe@gmail.com>, <jgg@ziepe.ca>, <leon@kernel.org>,
	Xiao Yang <yangx.jy@fujitsu.com>
Subject: [PATCH rdma-core v2] providers/rxe: Replace '%' with '&' in check_qp_queue_full()
Date: Fri, 21 Jan 2022 14:22:22 +0800	[thread overview]
Message-ID: <20220121062222.2914007-1-yangx.jy@fujitsu.com> (raw)

The expression "cons == ((qp->cur_index + 1) % q->index_mask)" doesn't
check the state of queue (full or empty) correctly.  For example:
If cons and qp->cur_index are 0 and q->index_mask is 1, the queue is actually
empty but check_qp_queue_full() reports full (ENOSPC).

Fixes: 1a894ca10105 ("Providers/rxe: Implement ibv_create_qp_ex verb")
Signed-off-by: Xiao Yang <yangx.jy@fujitsu.com>
---
 providers/rxe/rxe_queue.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/providers/rxe/rxe_queue.h b/providers/rxe/rxe_queue.h
index 6de8140c..708e76ac 100644
--- a/providers/rxe/rxe_queue.h
+++ b/providers/rxe/rxe_queue.h
@@ -205,7 +205,7 @@ static inline int check_qp_queue_full(struct rxe_qp *qp)
 	if (qp->err)
 		goto err;
 
-	if (cons == ((qp->cur_index + 1) % q->index_mask))
+	if (cons == ((qp->cur_index + 1) & q->index_mask))
 		qp->err = ENOSPC;
 err:
 	return qp->err;
-- 
2.25.1




             reply	other threads:[~2022-01-21  6:23 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-01-21  6:22 Xiao Yang [this message]
2022-01-21  6:47 ` [PATCH rdma-core v2] providers/rxe: Replace '%' with '&' in check_qp_queue_full() Bob Pearson
2022-01-23 11:04 ` Leon Romanovsky

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=20220121062222.2914007-1-yangx.jy@fujitsu.com \
    --to=yangx.jy@fujitsu.com \
    --cc=jgg@ziepe.ca \
    --cc=leon@kernel.org \
    --cc=linux-rdma@vger.kernel.org \
    --cc=rpearsonhpe@gmail.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