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Diffstat (limited to 'target/linux/layerscape/patches-5.4/809-jailhouse-0003-ivshmem-net-fix-race-in-state-machine.patch')
-rw-r--r--target/linux/layerscape/patches-5.4/809-jailhouse-0003-ivshmem-net-fix-race-in-state-machine.patch136
1 files changed, 136 insertions, 0 deletions
diff --git a/target/linux/layerscape/patches-5.4/809-jailhouse-0003-ivshmem-net-fix-race-in-state-machine.patch b/target/linux/layerscape/patches-5.4/809-jailhouse-0003-ivshmem-net-fix-race-in-state-machine.patch
new file mode 100644
index 0000000000..ae6f839011
--- /dev/null
+++ b/target/linux/layerscape/patches-5.4/809-jailhouse-0003-ivshmem-net-fix-race-in-state-machine.patch
@@ -0,0 +1,136 @@
+From 0af5d7d021bb899d9c3880415267e178a20fb7a9 Mon Sep 17 00:00:00 2001
+From: Mans Rullgard <mans@mansr.com>
+Date: Thu, 24 Nov 2016 18:46:41 +0000
+Subject: [PATCH] ivshmem-net: fix race in state machine
+
+(cherry picked from commit 5d663baed6a89d09bae4446f6509f9957c780bc7)
+---
+ drivers/net/ivshmem-net.c | 60 ++++++++++++++++++++++++-----------------------
+ 1 file changed, 31 insertions(+), 29 deletions(-)
+
+--- a/drivers/net/ivshmem-net.c
++++ b/drivers/net/ivshmem-net.c
+@@ -36,6 +36,8 @@
+ #define IVSHM_NET_STATE_READY 2
+ #define IVSHM_NET_STATE_RUN 3
+
++#define IVSHM_NET_FLAG_RUN 0
++
+ #define IVSHM_NET_MTU_MIN 256
+ #define IVSHM_NET_MTU_MAX 65535
+ #define IVSHM_NET_MTU_DEF 16384
+@@ -96,6 +98,8 @@ struct ivshm_net {
+ u32 lstate;
+ u32 rstate;
+
++ unsigned long flags;
++
+ struct workqueue_struct *state_wq;
+ struct work_struct state_work;
+
+@@ -529,12 +533,32 @@ static void ivshm_net_run(struct net_dev
+ {
+ struct ivshm_net *in = netdev_priv(ndev);
+
++ if (in->lstate < IVSHM_NET_STATE_READY)
++ return;
++
++ if (!netif_running(ndev))
++ return;
++
++ if (test_and_set_bit(IVSHM_NET_FLAG_RUN, &in->flags))
++ return;
++
+ netif_start_queue(ndev);
+ napi_enable(&in->napi);
+ napi_schedule(&in->napi);
+ ivshm_net_set_state(in, IVSHM_NET_STATE_RUN);
+ }
+
++static void ivshm_net_do_stop(struct net_device *ndev)
++{
++ struct ivshm_net *in = netdev_priv(ndev);
++
++ if (!test_and_clear_bit(IVSHM_NET_FLAG_RUN, &in->flags))
++ return;
++
++ netif_stop_queue(ndev);
++ napi_disable(&in->napi);
++}
++
+ static void ivshm_net_state_change(struct work_struct *work)
+ {
+ struct ivshm_net *in = container_of(work, struct ivshm_net, state_work);
+@@ -560,21 +584,13 @@ static void ivshm_net_state_change(struc
+ break;
+
+ case IVSHM_NET_STATE_READY:
++ case IVSHM_NET_STATE_RUN:
+ if (rstate >= IVSHM_NET_STATE_READY) {
+ netif_carrier_on(ndev);
+- if (ndev->flags & IFF_UP)
+- ivshm_net_run(ndev);
++ ivshm_net_run(ndev);
+ } else {
+ netif_carrier_off(ndev);
+- ivshm_net_set_state(in, IVSHM_NET_STATE_RESET);
+- }
+- break;
+-
+- case IVSHM_NET_STATE_RUN:
+- if (rstate < IVSHM_NET_STATE_READY) {
+- netif_stop_queue(ndev);
+- napi_disable(&in->napi);
+- netif_carrier_off(ndev);
++ ivshm_net_do_stop(ndev);
+ ivshm_net_set_state(in, IVSHM_NET_STATE_RESET);
+ }
+ break;
+@@ -584,18 +600,13 @@ static void ivshm_net_state_change(struc
+ WRITE_ONCE(in->rstate, rstate);
+ }
+
+-static bool ivshm_net_check_state(struct net_device *ndev)
++static void ivshm_net_check_state(struct net_device *ndev)
+ {
+ struct ivshm_net *in = netdev_priv(ndev);
+ u32 rstate = readl(&in->ivshm_regs->rstate);
+
+- if (rstate != READ_ONCE(in->rstate) ||
+- in->lstate != IVSHM_NET_STATE_RUN) {
++ if (rstate != in->rstate || !test_bit(IVSHM_NET_FLAG_RUN, &in->flags))
+ queue_work(in->state_wq, &in->state_work);
+- return false;
+- }
+-
+- return true;
+ }
+
+ static irqreturn_t ivshm_net_int(int irq, void *data)
+@@ -617,24 +628,15 @@ static int ivshm_net_open(struct net_dev
+
+ netdev_reset_queue(ndev);
+ ndev->operstate = IF_OPER_UP;
+-
+- if (in->lstate == IVSHM_NET_STATE_READY)
+- ivshm_net_run(ndev);
++ ivshm_net_run(ndev);
+
+ return 0;
+ }
+
+ static int ivshm_net_stop(struct net_device *ndev)
+ {
+- struct ivshm_net *in = netdev_priv(ndev);
+-
+ ndev->operstate = IF_OPER_DOWN;
+-
+- if (in->lstate == IVSHM_NET_STATE_RUN) {
+- napi_disable(&in->napi);
+- netif_stop_queue(ndev);
+- ivshm_net_set_state(in, IVSHM_NET_STATE_READY);
+- }
++ ivshm_net_do_stop(ndev);
+
+ return 0;
+ }