netdev - [PATCH net v2 1/4] r8152: avoid start_xmit to call napi

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:   Wed, 25 Jan 2017 16:13:18 +0800
From:   Hayes Wang <hayeswang@...ltek.com>
To:     <netdev@...r.kernel.org>
CC:     <nic_swsd@...ltek.com>, <linux-kernel@...r.kernel.org>,
        <linux-usb@...r.kernel.org>, Hayes Wang <hayeswang@...ltek.com>
Subject: [PATCH net v2 1/4] r8152: avoid start_xmit to call napi_schedule during autosuspend

Adjust the setting of the flag of SELECTIVE_SUSPEND to prevent start_xmit()
from calling napi_schedule() directly during runtime suspend.

After calling napi_disable() or clearing the flag of WORK_ENABLE,
scheduling the napi is useless.

Signed-off-by: Hayes Wang <hayeswang@...ltek.com>
---
 drivers/net/usb/r8152.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c
index e1466b4..23bef8e 100644
--- a/drivers/net/usb/r8152.c
+++ b/drivers/net/usb/r8152.c
@@ -3585,10 +3585,15 @@ static int rtl8152_rumtime_suspend(struct r8152 *tp)
 	struct net_device *netdev = tp->netdev;
 	int ret = 0;
 
+	set_bit(SELECTIVE_SUSPEND, &tp->flags);
+	smp_mb__after_atomic();
+
 	if (netif_running(netdev) && test_bit(WORK_ENABLE, &tp->flags)) {
 		u32 rcr = 0;
 
 		if (delay_autosuspend(tp)) {
+			clear_bit(SELECTIVE_SUSPEND, &tp->flags);
+			smp_mb__after_atomic();
 			ret = -EBUSY;
 			goto out1;
 		}
@@ -3605,6 +3610,8 @@ static int rtl8152_rumtime_suspend(struct r8152 *tp)
 			if (!(ocp_data & RXFIFO_EMPTY)) {
 				rxdy_gated_en(tp, false);
 				ocp_write_dword(tp, MCU_TYPE_PLA, PLA_RCR, rcr);
+				clear_bit(SELECTIVE_SUSPEND, &tp->flags);
+				smp_mb__after_atomic();
 				ret = -EBUSY;
 				goto out1;
 			}
@@ -3624,8 +3631,6 @@ static int rtl8152_rumtime_suspend(struct r8152 *tp)
 		}
 	}
 
-	set_bit(SELECTIVE_SUSPEND, &tp->flags);
-
 out1:
 	return ret;
 }
@@ -3681,12 +3686,13 @@ static int rtl8152_resume(struct usb_interface *intf)
 	if (netif_running(tp->netdev) && tp->netdev->flags & IFF_UP) {
 		if (test_bit(SELECTIVE_SUSPEND, &tp->flags)) {
 			tp->rtl_ops.autosuspend_en(tp, false);
-			clear_bit(SELECTIVE_SUSPEND, &tp->flags);
 			napi_disable(&tp->napi);
 			set_bit(WORK_ENABLE, &tp->flags);
 			if (netif_carrier_ok(tp->netdev))
 				rtl_start_rx(tp);
 			napi_enable(&tp->napi);
+			clear_bit(SELECTIVE_SUSPEND, &tp->flags);
+			smp_mb__after_atomic();
 		} else {
 			tp->rtl_ops.up(tp);
 			netif_carrier_off(tp->netdev);
-- 
2.7.4