diff options
Diffstat (limited to 'target/linux/layerscape/patches-5.4/701-net-0191-dpaa2-eth-Avoid-unbounded-while-loops.patch')
| -rw-r--r-- | target/linux/layerscape/patches-5.4/701-net-0191-dpaa2-eth-Avoid-unbounded-while-loops.patch | 160 |
1 files changed, 0 insertions, 160 deletions
diff --git a/target/linux/layerscape/patches-5.4/701-net-0191-dpaa2-eth-Avoid-unbounded-while-loops.patch b/target/linux/layerscape/patches-5.4/701-net-0191-dpaa2-eth-Avoid-unbounded-while-loops.patch deleted file mode 100644 index 72b41a45bb..0000000000 --- a/target/linux/layerscape/patches-5.4/701-net-0191-dpaa2-eth-Avoid-unbounded-while-loops.patch +++ /dev/null @@ -1,160 +0,0 @@ -From 3420c5bf9d08df074b67c7feda8a37d951d0b232 Mon Sep 17 00:00:00 2001 -From: Ioana Radulescu <ruxandra.radulescu@nxp.com> -Date: Wed, 18 Sep 2019 13:31:07 +0300 -Subject: [PATCH] dpaa2-eth: Avoid unbounded while loops - -Throughout the driver there are several places where we wait -indefinitely for DPIO portal commands to be executed, while -the portal returns a busy response code. - -Even though in theory we are guaranteed the portals become -available eventually, in practice the QBMan hardware module -may become unresponsive in various corner cases. - -Make sure we can never get stuck in an infinite while loop -by adding a retry counter for all portal commands. - -Signed-off-by: Ioana Radulescu <ruxandra.radulescu@nxp.com> ---- - drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c | 30 ++++++++++++++++++++---- - drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h | 8 +++++++ - 2 files changed, 33 insertions(+), 5 deletions(-) - ---- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c -+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c -@@ -221,6 +221,7 @@ static void xdp_release_buf(struct dpaa2 - struct dpaa2_eth_channel *ch, - dma_addr_t addr) - { -+ int retries = 0; - int err; - - ch->xdp.drop_bufs[ch->xdp.drop_cnt++] = addr; -@@ -229,8 +230,11 @@ static void xdp_release_buf(struct dpaa2 - - while ((err = dpaa2_io_service_release(ch->dpio, priv->bpid, - ch->xdp.drop_bufs, -- ch->xdp.drop_cnt)) == -EBUSY) -+ ch->xdp.drop_cnt)) == -EBUSY) { -+ if (retries++ >= DPAA2_ETH_SWP_BUSY_RETRIES) -+ break; - cpu_relax(); -+ } - - if (err) { - free_bufs(priv, ch->xdp.drop_bufs, ch->xdp.drop_cnt); -@@ -458,7 +462,7 @@ static int consume_frames(struct dpaa2_e - struct dpaa2_eth_fq *fq = NULL; - struct dpaa2_dq *dq; - const struct dpaa2_fd *fd; -- int cleaned = 0; -+ int cleaned = 0, retries = 0; - int is_last; - - do { -@@ -469,6 +473,11 @@ static int consume_frames(struct dpaa2_e - * the store until we get some sort of valid response - * token (either a valid frame or an "empty dequeue") - */ -+ if (retries++ >= DPAA2_ETH_SWP_BUSY_RETRIES) { -+ netdev_err_once(priv->net_dev, -+ "Unable to read a valid dequeue response\n"); -+ return 0; -+ } - continue; - } - -@@ -477,6 +486,7 @@ static int consume_frames(struct dpaa2_e - - fq->consume(priv, ch, fd, fq); - cleaned++; -+ retries = 0; - } while (!is_last); - - if (!cleaned) -@@ -949,6 +959,7 @@ static int add_bufs(struct dpaa2_eth_pri - u64 buf_array[DPAA2_ETH_BUFS_PER_CMD]; - struct page *page; - dma_addr_t addr; -+ int retries = 0; - int i, err; - - for (i = 0; i < DPAA2_ETH_BUFS_PER_CMD; i++) { -@@ -980,8 +991,11 @@ static int add_bufs(struct dpaa2_eth_pri - release_bufs: - /* In case the portal is busy, retry until successful */ - while ((err = dpaa2_io_service_release(ch->dpio, bpid, -- buf_array, i)) == -EBUSY) -+ buf_array, i)) == -EBUSY) { -+ if (retries++ >= DPAA2_ETH_SWP_BUSY_RETRIES) -+ break; - cpu_relax(); -+ } - - /* If release command failed, clean up and bail out; - * not much else we can do about it -@@ -1032,16 +1046,21 @@ static int seed_pool(struct dpaa2_eth_pr - static void drain_bufs(struct dpaa2_eth_priv *priv, int count) - { - u64 buf_array[DPAA2_ETH_BUFS_PER_CMD]; -+ int retries = 0; - int ret; - - do { - ret = dpaa2_io_service_acquire(NULL, priv->bpid, - buf_array, count); - if (ret < 0) { -+ if (ret == -EBUSY && -+ retries++ >= DPAA2_ETH_SWP_BUSY_RETRIES) -+ continue; - netdev_err(priv->net_dev, "dpaa2_io_service_acquire() failed\n"); - return; - } - free_bufs(priv, buf_array, ret); -+ retries = 0; - } while (ret); - } - -@@ -1094,7 +1113,7 @@ static int pull_channel(struct dpaa2_eth - ch->store); - dequeues++; - cpu_relax(); -- } while (err == -EBUSY); -+ } while (err == -EBUSY && dequeues < DPAA2_ETH_SWP_BUSY_RETRIES); - - ch->stats.dequeue_portal_busy += dequeues; - if (unlikely(err)) -@@ -1118,6 +1137,7 @@ static int dpaa2_eth_poll(struct napi_st - struct netdev_queue *nq; - int store_cleaned, work_done; - struct list_head rx_list; -+ int retries = 0; - int err; - - ch = container_of(napi, struct dpaa2_eth_channel, napi); -@@ -1163,7 +1183,7 @@ static int dpaa2_eth_poll(struct napi_st - do { - err = dpaa2_io_service_rearm(ch->dpio, &ch->nctx); - cpu_relax(); -- } while (err == -EBUSY); -+ } while (err == -EBUSY && retries++ < DPAA2_ETH_SWP_BUSY_RETRIES); - WARN_ONCE(err, "CDAN notifications rearm failed on core %d", - ch->nctx.desired_cpu); - ---- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h -+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h -@@ -245,6 +245,14 @@ static inline struct dpaa2_faead *dpaa2_ - */ - #define DPAA2_ETH_ENQUEUE_RETRIES 10 - -+/* Number of times to retry DPIO portal operations while waiting -+ * for portal to finish executing current command and become -+ * available. We want to avoid being stuck in a while loop in case -+ * hardware becomes unresponsive, but not give up too easily if -+ * the portal really is busy for valid reasons -+ */ -+#define DPAA2_ETH_SWP_BUSY_RETRIES 1000 -+ - /* Driver statistics, other than those in struct rtnl_link_stats64. - * These are usually collected per-CPU and aggregated by ethtool. - */ |