diff options
Diffstat (limited to 'patches/net-Write-lock-dev_base_lock-without-disabling-botto.patch')
| -rw-r--r-- | patches/net-Write-lock-dev_base_lock-without-disabling-botto.patch | 154 |
1 files changed, 0 insertions, 154 deletions
diff --git a/patches/net-Write-lock-dev_base_lock-without-disabling-botto.patch b/patches/net-Write-lock-dev_base_lock-without-disabling-botto.patch deleted file mode 100644 index 995f88e6716c..000000000000 --- a/patches/net-Write-lock-dev_base_lock-without-disabling-botto.patch +++ /dev/null @@ -1,154 +0,0 @@ -From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> -Date: Fri, 26 Nov 2021 17:15:29 +0100 -Subject: [PATCH] net: Write lock dev_base_lock without disabling bottom - halves. - -The writer acquires dev_base_lock with disabled bottom halves. -The reader can acquire dev_base_lock without disabling bottom halves -because there is no writer in softirq context. - -On PREEMPT_RT the softirqs are preemptible and local_bh_disable() acts -as a lock to ensure that resources, that are protected by disabling -bottom halves, remain protected. -This leads to a circular locking dependency if the lock acquired with -disabled bottom halves (as in write_lock_bh()) and somewhere else with -enabled bottom halves (as by read_lock() in netstat_show()) followed by -disabling bottom halves (cxgb_get_stats() -> t4_wr_mbox_meat_timeout() --> spin_lock_bh()). This is the reverse locking order. - -All read_lock() invocation are from sysfs callback which are not invoked -from softirq context. Therefore there is no need to disable bottom -halves while acquiring a write lock. - -Acquire the write lock of dev_base_lock without disabling bottom halves. - -Cc: stable-rt@vger.kernel.org -Reported-by: Pei Zhang <pezhang@redhat.com> -Reported-by: Luis Claudio R. Goncalves <lgoncalv@redhat.com> -Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> -Link: https://lore.kernel.org/r/20211126161529.hwqbkv6z2svox3zs@linutronix.de ---- - net/core/dev.c | 16 ++++++++-------- - net/core/link_watch.c | 4 ++-- - net/core/rtnetlink.c | 8 ++++---- - net/hsr/hsr_device.c | 6 +++--- - 4 files changed, 17 insertions(+), 17 deletions(-) - ---- a/net/core/dev.c -+++ b/net/core/dev.c -@@ -371,12 +371,12 @@ static void list_netdevice(struct net_de - - ASSERT_RTNL(); - -- write_lock_bh(&dev_base_lock); -+ write_lock(&dev_base_lock); - list_add_tail_rcu(&dev->dev_list, &net->dev_base_head); - netdev_name_node_add(net, dev->name_node); - hlist_add_head_rcu(&dev->index_hlist, - dev_index_hash(net, dev->ifindex)); -- write_unlock_bh(&dev_base_lock); -+ write_unlock(&dev_base_lock); - - dev_base_seq_inc(net); - } -@@ -389,11 +389,11 @@ static void unlist_netdevice(struct net_ - ASSERT_RTNL(); - - /* Unlink dev from the device chain */ -- write_lock_bh(&dev_base_lock); -+ write_lock(&dev_base_lock); - list_del_rcu(&dev->dev_list); - netdev_name_node_del(dev->name_node); - hlist_del_rcu(&dev->index_hlist); -- write_unlock_bh(&dev_base_lock); -+ write_unlock(&dev_base_lock); - - dev_base_seq_inc(dev_net(dev)); - } -@@ -1272,15 +1272,15 @@ int dev_change_name(struct net_device *d - - netdev_adjacent_rename_links(dev, oldname); - -- write_lock_bh(&dev_base_lock); -+ write_lock(&dev_base_lock); - netdev_name_node_del(dev->name_node); -- write_unlock_bh(&dev_base_lock); -+ write_unlock(&dev_base_lock); - - synchronize_rcu(); - -- write_lock_bh(&dev_base_lock); -+ write_lock(&dev_base_lock); - netdev_name_node_add(net, dev->name_node); -- write_unlock_bh(&dev_base_lock); -+ write_unlock(&dev_base_lock); - - ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev); - ret = notifier_to_errno(ret); ---- a/net/core/link_watch.c -+++ b/net/core/link_watch.c -@@ -55,7 +55,7 @@ static void rfc2863_policy(struct net_de - if (operstate == dev->operstate) - return; - -- write_lock_bh(&dev_base_lock); -+ write_lock(&dev_base_lock); - - switch(dev->link_mode) { - case IF_LINK_MODE_TESTING: -@@ -74,7 +74,7 @@ static void rfc2863_policy(struct net_de - - dev->operstate = operstate; - -- write_unlock_bh(&dev_base_lock); -+ write_unlock(&dev_base_lock); - } - - ---- a/net/core/rtnetlink.c -+++ b/net/core/rtnetlink.c -@@ -842,9 +842,9 @@ static void set_operstate(struct net_dev - } - - if (dev->operstate != operstate) { -- write_lock_bh(&dev_base_lock); -+ write_lock(&dev_base_lock); - dev->operstate = operstate; -- write_unlock_bh(&dev_base_lock); -+ write_unlock(&dev_base_lock); - netdev_state_change(dev); - } - } -@@ -2779,11 +2779,11 @@ static int do_setlink(const struct sk_bu - if (tb[IFLA_LINKMODE]) { - unsigned char value = nla_get_u8(tb[IFLA_LINKMODE]); - -- write_lock_bh(&dev_base_lock); -+ write_lock(&dev_base_lock); - if (dev->link_mode ^ value) - status |= DO_SETLINK_NOTIFY; - dev->link_mode = value; -- write_unlock_bh(&dev_base_lock); -+ write_unlock(&dev_base_lock); - } - - if (tb[IFLA_VFINFO_LIST]) { ---- a/net/hsr/hsr_device.c -+++ b/net/hsr/hsr_device.c -@@ -30,13 +30,13 @@ static bool is_slave_up(struct net_devic - - static void __hsr_set_operstate(struct net_device *dev, int transition) - { -- write_lock_bh(&dev_base_lock); -+ write_lock(&dev_base_lock); - if (dev->operstate != transition) { - dev->operstate = transition; -- write_unlock_bh(&dev_base_lock); -+ write_unlock(&dev_base_lock); - netdev_state_change(dev); - } else { -- write_unlock_bh(&dev_base_lock); -+ write_unlock(&dev_base_lock); - } - } - |