netdev - [PATCH net-next 16/16] sfc: Don't receive packets when the napi budget == 0

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 14 Mar 2014 18:11:22 -0700
From:	ebiederm@...ssion.com (Eric W. Biederman)
To:	David Miller <davem@...emloft.net>
Cc:	eric.dumazet@...il.com, netdev@...r.kernel.org,
	xiyou.wangcong@...il.com, mpm@...enic.com, satyam.sharma@...il.com
Subject: [PATCH net-next 16/16] sfc: Don't receive packets when the napi budget == 0


Processing any incoming packets with a with a napi budget of 0
is incorrect driver behavior.

This matters as netpoll will shortly call drivers with a budget of 0
to avoid receive packet processing happening in hard irq context.

Signed-off-by: "Eric W. Biederman" <ebiederm@...ssion.com>
---
 drivers/net/ethernet/sfc/ef10.c  |    3 +++
 drivers/net/ethernet/sfc/farch.c |    3 +++
 2 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/net/ethernet/sfc/ef10.c b/drivers/net/ethernet/sfc/ef10.c
index eb75675f6e32..651626e133f9 100644
--- a/drivers/net/ethernet/sfc/ef10.c
+++ b/drivers/net/ethernet/sfc/ef10.c
@@ -1955,6 +1955,9 @@ static int efx_ef10_ev_process(struct efx_channel *channel, int quota)
 	int tx_descs = 0;
 	int spent = 0;
 
+	if (quota <= 0)
+		return spent;
+
 	read_ptr = channel->eventq_read_ptr;
 
 	for (;;) {
diff --git a/drivers/net/ethernet/sfc/farch.c b/drivers/net/ethernet/sfc/farch.c
index aa1b169f45ec..a08761360cdf 100644
--- a/drivers/net/ethernet/sfc/farch.c
+++ b/drivers/net/ethernet/sfc/farch.c
@@ -1248,6 +1248,9 @@ int efx_farch_ev_process(struct efx_channel *channel, int budget)
 	int tx_packets = 0;
 	int spent = 0;
 
+	if (budget <= 0)
+		return spent;
+
 	read_ptr = channel->eventq_read_ptr;
 
 	for (;;) {
-- 
1.7.5.4

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html