This is a note to let you know that I've just added the patch titled bonding: fix feature flag setting at init time to the 5.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: bonding-fix-feature-flag-setting-at-init-time.patch and it can be found in the queue-5.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Sat Dec 19 11:38:44 AM CET 2020 From: Jarod Wilson <jarod@xxxxxxxxxx> Date: Sat, 5 Dec 2020 12:22:29 -0500 Subject: bonding: fix feature flag setting at init time From: Jarod Wilson <jarod@xxxxxxxxxx> [ Upstream commit 007ab5345545aba2f9cbe4c096cc35d2fd3275ac ] Don't try to adjust XFRM support flags if the bond device isn't yet registered. Bad things can currently happen when netdev_change_features() is called without having wanted_features fully filled in yet. This code runs both on post-module-load mode changes, as well as at module init time, and when run at module init time, it is before register_netdevice() has been called and filled in wanted_features. The empty wanted_features led to features also getting emptied out, which was definitely not the intended behavior, so prevent that from happening. Originally, I'd hoped to stop adjusting wanted_features at all in the bonding driver, as it's documented as being something only the network core should touch, but we actually do need to do this to properly update both the features and wanted_features fields when changing the bond type, or we get to a situation where ethtool sees: esp-hw-offload: off [requested on] I do think we should be using netdev_update_features instead of netdev_change_features here though, so we only send notifiers when the features actually changed. Fixes: a3b658cfb664 ("bonding: allow xfrm offload setup post-module-load") Reported-by: Ivan Vecera <ivecera@xxxxxxxxxx> Suggested-by: Ivan Vecera <ivecera@xxxxxxxxxx> Cc: Jay Vosburgh <j.vosburgh@xxxxxxxxx> Cc: Veaceslav Falico <vfalico@xxxxxxxxx> Cc: Andy Gospodarek <andy@xxxxxxxxxxxxx> Signed-off-by: Jarod Wilson <jarod@xxxxxxxxxx> Link: https://lore.kernel.org/r/20201205172229.576587-1-jarod@xxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/bonding/bond_options.c | 22 +++++++++++++++------- include/net/bonding.h | 2 -- 2 files changed, 15 insertions(+), 9 deletions(-) --- a/drivers/net/bonding/bond_options.c +++ b/drivers/net/bonding/bond_options.c @@ -745,6 +745,19 @@ const struct bond_option *bond_opt_get(u return &bond_opts[option]; } +static void bond_set_xfrm_features(struct net_device *bond_dev, u64 mode) +{ + if (!IS_ENABLED(CONFIG_XFRM_OFFLOAD)) + return; + + if (mode == BOND_MODE_ACTIVEBACKUP) + bond_dev->wanted_features |= BOND_XFRM_FEATURES; + else + bond_dev->wanted_features &= ~BOND_XFRM_FEATURES; + + netdev_update_features(bond_dev); +} + static int bond_option_mode_set(struct bonding *bond, const struct bond_opt_value *newval) { @@ -767,13 +780,8 @@ static int bond_option_mode_set(struct b if (newval->value == BOND_MODE_ALB) bond->params.tlb_dynamic_lb = 1; -#ifdef CONFIG_XFRM_OFFLOAD - if (newval->value == BOND_MODE_ACTIVEBACKUP) - bond->dev->wanted_features |= BOND_XFRM_FEATURES; - else - bond->dev->wanted_features &= ~BOND_XFRM_FEATURES; - netdev_change_features(bond->dev); -#endif /* CONFIG_XFRM_OFFLOAD */ + if (bond->dev->reg_state == NETREG_REGISTERED) + bond_set_xfrm_features(bond->dev, newval->value); /* don't cache arp_validate between modes */ bond->params.arp_validate = BOND_ARP_VALIDATE_NONE; --- a/include/net/bonding.h +++ b/include/net/bonding.h @@ -86,10 +86,8 @@ #define bond_for_each_slave_rcu(bond, pos, iter) \ netdev_for_each_lower_private_rcu((bond)->dev, pos, iter) -#ifdef CONFIG_XFRM_OFFLOAD #define BOND_XFRM_FEATURES (NETIF_F_HW_ESP | NETIF_F_HW_ESP_TX_CSUM | \ NETIF_F_GSO_ESP) -#endif /* CONFIG_XFRM_OFFLOAD */ #ifdef CONFIG_NET_POLL_CONTROLLER extern atomic_t netpoll_block_tx; Patches currently in stable-queue which might be from jarod@xxxxxxxxxx are queue-5.9/bonding-fix-feature-flag-setting-at-init-time.patch