The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x 6db541ae279bd4e76dbd939e5fbf298396166242 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable@xxxxxxxxxxxxxxx>' --in-reply-to '2023081208-trinity-upfront-c2e1@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: 6db541ae279b ("ibmvnic: Ensure login failure recovery is safe from other resets") 23cc5f667453 ("ibmvnic: Do partial reset on login failure") 61772b0908c6 ("ibmvnic: don't release napi in __ibmvnic_open()") b6ee566cf394 ("ibmvnic: Update driver return codes") bbd809305bc7 ("ibmvnic: Reuse tx pools when possible") 489de956e7a2 ("ibmvnic: Reuse rx pools when possible") f8ac0bfa7d7a ("ibmvnic: Reuse LTB when possible") 129854f061d8 ("ibmvnic: Use bitmap for LTB map_ids") 0d1af4fa7124 ("ibmvnic: init_tx_pools move loop-invariant code") 8243c7ed6d08 ("ibmvnic: Use/rename local vars in init_tx_pools") 0df7b9ad8f84 ("ibmvnic: Use/rename local vars in init_rx_pools") 0f2bf3188c43 ("ibmvnic: Fix up some comments and messages") 38106b2c433e ("ibmvnic: Consolidate code in replenish_rx_pool()") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 6db541ae279bd4e76dbd939e5fbf298396166242 Mon Sep 17 00:00:00 2001 From: Nick Child <nnac123@xxxxxxxxxxxxx> Date: Wed, 9 Aug 2023 17:10:38 -0500 Subject: [PATCH] ibmvnic: Ensure login failure recovery is safe from other resets If a login request fails, the recovery process should be protected against parallel resets. It is a known issue that freeing and registering CRQ's in quick succession can result in a failover CRQ from the VIOS. Processing a failover during login recovery is dangerous for two reasons: 1. This will result in two parallel initialization processes, this can cause serious issues during login. 2. It is possible that the failover CRQ is received but never executed. We get notified of a pending failover through a transport event CRQ. The reset is not performed until a INIT CRQ request is received. Previously, if CRQ init fails during login recovery, then the ibmvnic irq is freed and the login process returned error. If failover_pending is true (a transport event was received), then the ibmvnic device would never be able to process the reset since it cannot receive the CRQ_INIT request due to the irq being freed. This leaved the device in a inoperable state. Therefore, the login failure recovery process must be hardened against these possible issues. Possible failovers (due to quick CRQ free and init) must be avoided and any issues during re-initialization should be dealt with instead of being propagated up the stack. This logic is similar to that of ibmvnic_probe(). Fixes: dff515a3e71d ("ibmvnic: Harden device login requests") Signed-off-by: Nick Child <nnac123@xxxxxxxxxxxxx> Reviewed-by: Simon Horman <horms@xxxxxxxxxx> Link: https://lore.kernel.org/r/20230809221038.51296-5-nnac123@xxxxxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index e9619957d58a..df76cdaddcfb 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -116,6 +116,7 @@ static void ibmvnic_tx_scrq_clean_buffer(struct ibmvnic_adapter *adapter, static void free_long_term_buff(struct ibmvnic_adapter *adapter, struct ibmvnic_long_term_buff *ltb); static void ibmvnic_disable_irqs(struct ibmvnic_adapter *adapter); +static void flush_reset_queue(struct ibmvnic_adapter *adapter); struct ibmvnic_stat { char name[ETH_GSTRING_LEN]; @@ -1507,8 +1508,8 @@ static const char *adapter_state_to_string(enum vnic_state state) static int ibmvnic_login(struct net_device *netdev) { + unsigned long flags, timeout = msecs_to_jiffies(20000); struct ibmvnic_adapter *adapter = netdev_priv(netdev); - unsigned long timeout = msecs_to_jiffies(20000); int retry_count = 0; int retries = 10; bool retry; @@ -1573,6 +1574,7 @@ static int ibmvnic_login(struct net_device *netdev) "SCRQ irq initialization failed\n"); return rc; } + /* Default/timeout error handling, reset and start fresh */ } else if (adapter->init_done_rc) { netdev_warn(netdev, "Adapter login failed, init_done_rc = %d\n", adapter->init_done_rc); @@ -1588,29 +1590,53 @@ static int ibmvnic_login(struct net_device *netdev) "Freeing and re-registering CRQs before attempting to login again\n"); retry = true; adapter->init_done_rc = 0; - retry_count++; release_sub_crqs(adapter, true); - reinit_init_done(adapter); - release_crq_queue(adapter); - /* If we don't sleep here then we risk an unnecessary - * failover event from the VIOS. This is a known VIOS - * issue caused by a vnic device freeing and registering - * a CRQ too quickly. + /* Much of this is similar logic as ibmvnic_probe(), + * we are essentially re-initializing communication + * with the server. We really should not run any + * resets/failovers here because this is already a form + * of reset and we do not want parallel resets occurring */ - msleep(1500); - rc = init_crq_queue(adapter); - if (rc) { - netdev_err(netdev, "login recovery: init CRQ failed %d\n", - rc); - return -EIO; - } + do { + reinit_init_done(adapter); + /* Clear any failovers we got in the previous + * pass since we are re-initializing the CRQ + */ + adapter->failover_pending = false; + release_crq_queue(adapter); + /* If we don't sleep here then we risk an + * unnecessary failover event from the VIOS. + * This is a known VIOS issue caused by a vnic + * device freeing and registering a CRQ too + * quickly. + */ + msleep(1500); + /* Avoid any resets, since we are currently + * resetting. + */ + spin_lock_irqsave(&adapter->rwi_lock, flags); + flush_reset_queue(adapter); + spin_unlock_irqrestore(&adapter->rwi_lock, + flags); - rc = ibmvnic_reset_init(adapter, false); - if (rc) { - netdev_err(netdev, "login recovery: Reset init failed %d\n", - rc); - return -EIO; - } + rc = init_crq_queue(adapter); + if (rc) { + netdev_err(netdev, "login recovery: init CRQ failed %d\n", + rc); + return -EIO; + } + + rc = ibmvnic_reset_init(adapter, false); + if (rc) + netdev_err(netdev, "login recovery: Reset init failed %d\n", + rc); + /* IBMVNIC_CRQ_INIT will return EAGAIN if it + * fails, since ibmvnic_reset_init will free + * irq's in failure, we won't be able to receive + * new CRQs so we need to keep trying. probe() + * handles this similarly. + */ + } while (rc == -EAGAIN && retry_count++ < retries); } } while (retry);
