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* net: fix problem in reading sock TX queueTom Herbert2010-07-141-4/+3
| | | | | | | | | | | | | | | | | | | | | Fix problem in reading the tx_queue recorded in a socket. In dev_pick_tx, the TX queue is read by doing a check with sk_tx_queue_recorded on the socket, followed by a sk_tx_queue_get. The problem is that there is not mutual exclusion across these calls in the socket so it it is possible that the queue in the sock can be invalidated after sk_tx_queue_recorded is called so that sk_tx_queue get returns -1, which sets 65535 in queue_index and thus dev_pick_tx returns 65536 which is a bogus queue and can cause crash in dev_queue_xmit. We fix this by only calling sk_tx_queue_get which does the proper checks. The interface is that sk_tx_queue_get returns the TX queue if the sock argument is non-NULL and TX queue is recorded, else it returns -1. sk_tx_queue_recorded is no longer used so it can be completely removed. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net/core: neighbour update OopsDoug Kehn2010-07-141-1/+4
| | | | | | | | | | | | | | | | | | | | When configuring DMVPN (GRE + openNHRP) and a GRE remote address is configured a kernel Oops is observed. The obserseved Oops is caused by a NULL header_ops pointer (neigh->dev->header_ops) in neigh_update_hhs() when void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *) = neigh->dev->header_ops->cache_update; is executed. The dev associated with the NULL header_ops is the GRE interface. This patch guards against the possibility that header_ops is NULL. This Oops was first observed in kernel version 2.6.26.8. Signed-off-by: Doug Kehn <rdkehn@yahoo.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: skb_tx_hash() fix relative to skb_orphan_try()Eric Dumazet2010-07-141-3/+10
| | | | | | | | | | | | | | | | | | | | commit fc6055a5ba31e2 (net: Introduce skb_orphan_try()) added early orphaning of skbs. This unfortunately added a performance regression in skb_tx_hash() in case of stacked devices (bonding, vlans, ...) Since skb->sk is now NULL, we cannot access sk->sk_hash anymore to spread tx packets to multiple NIC queues on multiqueue devices. skb_tx_hash() in this case only uses skb->protocol, same value for all flows. skb_orphan_try() can copy sk->sk_hash into skb->rxhash and skb_tx_hash() can use this saved sk_hash value to compute its internal hash value. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: decreasing real_num_tx_queues needs to flush qdiscJohn Fastabend2010-07-021-0/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Reducing real_num_queues needs to flush the qdisc otherwise skbs with queue_mappings greater then real_num_tx_queues can be sent to the underlying driver. The flow for this is, dev_queue_xmit() dev_pick_tx() skb_tx_hash() => hash using real_num_tx_queues skb_set_queue_mapping() ... qdisc_enqueue_root() => enqueue skb on txq from hash ... dev->real_num_tx_queues -= n ... sch_direct_xmit() dev_hard_start_xmit() ndo_start_xmit(skb,dev) => skb queue set with old hash skbs are enqueued on the qdisc with skb->queue_mapping set 0 < queue_mappings < real_num_tx_queues. When the driver decreases real_num_tx_queues skb's may be dequeued from the qdisc with a queue_mapping greater then real_num_tx_queues. This fixes a case in ixgbe where this was occurring with DCB and FCoE. Because the driver is using queue_mapping to map skbs to tx descriptor rings we can potentially map skbs to rings that no longer exist. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Tested-by: Ross Brattain <ross.b.brattain@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ethtool: Fix potential user buffer overflow for ETHTOOL_{G, S}RXFHBen Hutchings2010-06-291-9/+27
| | | | | | | | | | | | | | | | | struct ethtool_rxnfc was originally defined in 2.6.27 for the ETHTOOL_{G,S}RXFH command with only the cmd, flow_type and data fields. It was then extended in 2.6.30 to support various additional commands. These commands should have been defined to use a new structure, but it is too late to change that now. Since user-space may still be using the old structure definition for the ETHTOOL_{G,S}RXFH commands, and since they do not need the additional fields, only copy the originally defined fields to and from user-space. Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Cc: stable@kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
* ethtool: Fix potential kernel buffer overflow in ETHTOOL_GRXCLSRLALLBen Hutchings2010-06-291-2/+3
| | | | | | | | | | | On a 32-bit machine, info.rule_cnt >= 0x40000000 leads to integer overflow and the buffer may be smaller than needed. Since ETHTOOL_GRXCLSRLALL is unprivileged, this can presumably be used for at least denial of service. Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Cc: stable@kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
* net: rxhash already set in __copy_skb_headerEric Dumazet2010-06-131-1/+0
| | | | | | | No need to copy rxhash again in __skb_clone() Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: fix deliver_no_wcard regression on loopback deviceJohn Fastabend2010-06-131-0/+1
| | | | | | | | | | | | deliver_no_wcard is not being set in skb_copy_header. In the skb_cloned case it is not being cleared and may cause the skb to be dropped when the loopback device pushes it back up the stack. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Tested-by: Markus Trippelsdorf <markus@trippelsdorf.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* pktgen: Fix accuracy of inter-packet delay.Daniel Turull2010-06-101-1/+1
| | | | | | | | | This patch correct a bug in the delay of pktgen. It makes sure the inter-packet interval is accurate. Signed-off-by: Daniel Turull <daniel.turull@gmail.com> Signed-off-by: Robert Olsson <robert.olsson@its.uu.se> Signed-off-by: David S. Miller <davem@davemloft.net>
* pkt_sched: gen_estimator: add a new lockEric Dumazet2010-06-101-3/+12
| | | | | | | | | | | | | gen_kill_estimator() / gen_new_estimator() is not always called with RTNL held. net/netfilter/xt_RATEEST.c is one user of these API that do not hold RTNL, so random corruptions can occur between "tc" and "iptables". Add a new fine grained lock instead of trying to use RTNL in netfilter. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: deliver skbs on inactive slaves to exact matchesJohn Fastabend2010-06-101-3/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, the accelerated receive path for VLAN's will drop packets if the real device is an inactive slave and is not one of the special pkts tested for in skb_bond_should_drop(). This behavior is different then the non-accelerated path and for pkts over a bonded vlan. For example, vlanx -> bond0 -> ethx will be dropped in the vlan path and not delivered to any packet handlers at all. However, bond0 -> vlanx -> ethx and bond0 -> ethx will be delivered to handlers that match the exact dev, because the VLAN path checks the real_dev which is not a slave and netif_recv_skb() doesn't drop frames but only delivers them to exact matches. This patch adds a sk_buff flag which is used for tagging skbs that would previously been dropped and allows the skb to continue to skb_netif_recv(). Here we add logic to check for the deliver_no_wcard flag and if it is set only deliver to handlers that match exactly. This makes both paths above consistent and gives pkt handlers a way to identify skbs that come from inactive slaves. Without this patch in some configurations skbs will be delivered to handlers with exact matches and in others be dropped out right in the vlan path. I have tested the following 4 configurations in failover modes and load balancing modes. # bond0 -> ethx # vlanx -> bond0 -> ethx # bond0 -> vlanx -> ethx # bond0 -> ethx | vlanx -> -- Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Print num_rx_queues imbalance warning only when there are allocated queuesTim Gardner2010-06-091-5/+3
| | | | | | | | | | | | | | BugLink: http://bugs.launchpad.net/bugs/591416 There are a number of network drivers (bridge, bonding, etc) that are not yet receive multi-queue enabled and use alloc_netdev(), so don't print a num_rx_queues imbalance warning in that case. Also, only print the warning once for those drivers that _are_ multi-queue enabled. Signed-off-by: Tim Gardner <tim.gardner@canonical.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
* net: fix conflict between null_or_orig and null_or_bondJohn Fastabend2010-06-021-4/+4
| | | | | | | | | | | | | | | | | If a skb is received on an inactive bond that does not meet the special cases checked for by skb_bond_should_drop it should only be delivered to exact matches as the comment in netif_receive_skb() says. However because null_or_bond could also be null this is not always true. This patch renames null_or_bond to orig_or_bond and initializes it to orig_dev. This keeps the intent of null_or_bond to pass frames received on VLAN interfaces stacked on bonding interfaces without invalidating the statement for null_or_orig. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sock_queue_err_skb() dont mess with sk_forward_allocEric Dumazet2010-05-311-2/+28
| | | | | | | | | | | | | | | | | Correct sk_forward_alloc handling for error_queue would need to use a backlog of frames that softirq handler could not deliver because socket is owned by user thread. Or extend backlog processing to be able to process normal and error packets. Another possibility is to not use mem charge for error queue, this is what I implemented in this patch. Note: this reverts commit 29030374 (net: fix sk_forward_alloc corruptions), since we dont need to lock socket anymore. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge branch 'master' of /home/davem/src/GIT/linux-2.6/David S. Miller2010-05-315-63/+79
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| * Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6Linus Torvalds2010-05-284-13/+53
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (22 commits) netlink: bug fix: wrong size was calculated for vfinfo list blob netlink: bug fix: don't overrun skbs on vf_port dump xt_tee: use skb_dst_drop() netdev/fec: fix ifconfig eth0 down hang issue cnic: Fix context memory init. on 5709. drivers/net: Eliminate a NULL pointer dereference drivers/net/hamradio: Eliminate a NULL pointer dereference be2net: Patch removes redundant while statement in loop. ipv6: Add GSO support on forwarding path net: fix __neigh_event_send() vhost: fix the memory leak which will happen when memory_access_ok fails vhost-net: fix to check the return value of copy_to/from_user() correctly vhost: fix to check the return value of copy_to/from_user() correctly vhost: Fix host panic if ioctl called with wrong index net: fix lock_sock_bh/unlock_sock_bh net/iucv: Add missing spin_unlock net: ll_temac: fix checksum offload logic net: ll_temac: fix interrupt bug when interrupt 0 is used sctp: dubious bitfields in sctp_transport ipmr: off by one in __ipmr_fill_mroute() ...
| * \ Merge branch 'perf-core-for-linus' of ↵Linus Torvalds2010-05-271-6/+6
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (61 commits) tracing: Add __used annotation to event variable perf, trace: Fix !x86 build bug perf report: Support multiple events on the TUI perf annotate: Fix up usage of the build id cache x86/mmiotrace: Remove redundant instruction prefix checks perf annotate: Add TUI interface perf tui: Remove annotate from popup menu after failure perf report: Don't start the TUI if -D is used perf: Fix getline undeclared perf: Optimize perf_tp_event_match() perf: Remove more code from the fastpath perf: Optimize the !vmalloc backed buffer perf: Optimize perf_output_copy() perf: Fix wakeup storm for RO mmap()s perf-record: Share per-cpu buffers perf-record: Remove -M perf: Ensure that IOC_OUTPUT isn't used to create multi-writer buffers perf, trace: Optimize tracepoints by using per-tracepoint-per-cpu hlist to track events perf, trace: Optimize tracepoints by removing IRQ-disable from perf/tracepoint interaction perf tui: Allow disabling the TUI on a per command basis in ~/.perfconfig ...
| | * \ Merge branch 'perf/core' of ↵Steven Rostedt2010-05-212-55/+115
| | |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip into trace/tip/tracing/core-7 Conflicts: include/linux/ftrace_event.h include/trace/ftrace.h kernel/trace/trace_event_perf.c kernel/trace/trace_kprobe.c kernel/trace/trace_syscalls.c Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| | * | | tracing: Let tracepoints have data passed to tracepoint callbacksSteven Rostedt2010-05-141-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds data to be passed to tracepoint callbacks. The created functions from DECLARE_TRACE() now need a mandatory data parameter. For example: DECLARE_TRACE(mytracepoint, int value, value) Will create the register function: int register_trace_mytracepoint((void(*)(void *data, int value))probe, void *data); As the first argument, all callbacks (probes) must take a (void *data) parameter. So a callback for the above tracepoint will look like: void myprobe(void *data, int value) { } The callback may choose to ignore the data parameter. This change allows callbacks to register a private data pointer along with the function probe. void mycallback(void *data, int value); register_trace_mytracepoint(mycallback, mydata); Then the mycallback() will receive the "mydata" as the first parameter before the args. A more detailed example: DECLARE_TRACE(mytracepoint, TP_PROTO(int status), TP_ARGS(status)); /* In the C file */ DEFINE_TRACE(mytracepoint, TP_PROTO(int status), TP_ARGS(status)); [...] trace_mytracepoint(status); /* In a file registering this tracepoint */ int my_callback(void *data, int status) { struct my_struct my_data = data; [...] } [...] my_data = kmalloc(sizeof(*my_data), GFP_KERNEL); init_my_data(my_data); register_trace_mytracepoint(my_callback, my_data); The same callback can also be registered to the same tracepoint as long as the data registered is different. Note, the data must also be used to unregister the callback: unregister_trace_mytracepoint(my_callback, my_data); Because of the data parameter, tracepoints declared this way can not have no args. That is: DECLARE_TRACE(mytracepoint, TP_PROTO(void), TP_ARGS()); will cause an error. If no arguments are needed, a new macro can be used instead: DECLARE_TRACE_NOARGS(mytracepoint); Since there are no arguments, the proto and args fields are left out. This is part of a series to make the tracepoint footprint smaller: text data bss dec hex filename 4913961 1088356 861512 6863829 68bbd5 vmlinux.orig 4914025 1088868 861512 6864405 68be15 vmlinux.class 4918492 1084612 861512 6864616 68bee8 vmlinux.tracepoint Again, this patch also increases the size of the kernel, but lays the ground work for decreasing it. v5: Fixed net/core/drop_monitor.c to handle these updates. v4: Moved the DECLARE_TRACE() DECLARE_TRACE_NOARGS out of the #ifdef CONFIG_TRACE_POINTS, since the two are the same in both cases. The __DECLARE_TRACE() is what changes. Thanks to Frederic Weisbecker for pointing this out. v3: Made all register_* functions require data to be passed and all callbacks to take a void * parameter as its first argument. This makes the calling functions comply with C standards. Also added more comments to the modifications of DECLARE_TRACE(). v2: Made the DECLARE_TRACE() have the ability to pass arguments and added a new DECLARE_TRACE_NOARGS() for tracepoints that do not need any arguments. Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * | | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6Linus Torvalds2010-05-254-22/+50
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (63 commits) drivers/net/usb/asix.c: Fix pointer cast. be2net: Bug fix to avoid disabling bottom half during firmware upgrade. proc_dointvec: write a single value hso: add support for new products Phonet: fix potential use-after-free in pep_sock_close() ath9k: remove VEOL support for ad-hoc ath9k: change beacon allocation to prefer the first beacon slot sock.h: fix kernel-doc warning cls_cgroup: Fix build error when built-in macvlan: do proper cleanup in macvlan_common_newlink() V2 be2net: Bug fix in init code in probe net/dccp: expansion of error code size ath9k: Fix rx of mcast/bcast frames in PS mode with auto sleep wireless: fix sta_info.h kernel-doc warnings wireless: fix mac80211.h kernel-doc warnings iwlwifi: testing the wrong variable in iwl_add_bssid_station() ath9k_htc: rare leak in ath9k_hif_usb_alloc_tx_urbs() ath9k_htc: dereferencing before check in hif_usb_tx_cb() rt2x00: Fix rt2800usb TX descriptor writing. rt2x00: Fix failed SLEEP->AWAKE and AWAKE->SLEEP transitions. ...
| * \ \ \ \ Merge branch 'master' into for-2.6.35Jens Axboe2010-05-2120-1441/+2731
| |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: fs/ext3/fsync.c Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| | * | | | | net: Expose all network devices in a namespaces in sysfsEric W. Biederman2010-05-213-39/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit aaf8cdc34ddba08122f02217d9d684e2f9f5d575. Drivers like the ipw2100 call device_create_group when they are initialized and device_remove_group when they are shutdown. Moving them between namespaces deletes their sysfs groups early. In particular the following call chain results. netdev_unregister_kobject -> device_del -> kobject_del -> sysfs_remove_dir With sysfs_remove_dir recursively deleting all of it's subdirectories, and nothing adding them back. Ouch! Therefore we need to call something that ultimate calls sysfs_mv_dir as that sysfs function can move sysfs directories between namespaces without deleting their subdirectories or their contents. Allowing us to avoid placing extra boiler plate into every driver that does something interesting with sysfs. Currently the function that provides that capability is device_rename. That is the code works without nasty side effects as originally written. So remove the misguided fix for moving devices between namespaces. The bug in the kobject layer that inspired it has now been recognized and fixed. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| | * | | | | net/sysfs: Fix the bitrot in network device kobject namespace supportEric W. Biederman2010-05-211-5/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I had a couple of stupid bugs in: netns: Teach network device kobjects which namespace they are in. - I duplicated the Kconfig for the NET_NS - The build was broken when sysfs was not compiled in The sysfs breakage is because after I moved the operations for the sysfs to the kobject layer, to make things cleaner I forgot to move the ifdefs. Opps. I'm not quite certain how I got introduced a second NET_NS Kconfig, but it was probably a 3 way merge somewhere along the way that did not notice that the NET_NS Kconfig option had mvoed and thout that was a bug. It probably slipped in because it used to be the sysfs patches were the first patches in my network namespace patches. Some things just don't go like you would expect. Neither of these bugs actually affect anything in the common case but they should be fixed. Thanks to Serge for noticing they were present. Reported-by: Serge E. Hallyn <serue@us.ibm.com> Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Acked-by: David S. Miller <davem@davemloft.net>
| | * | | | | netns: Teach network device kobjects which namespace they are in.Eric W. Biederman2010-05-211-0/+47
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The problem. Network devices show up in sysfs and with the network namespace active multiple devices with the same name can show up in the same directory, ouch! To avoid that problem and allow existing applications in network namespaces to see the same interface that is currently presented in sysfs, this patch enables the tagging directory support in sysfs. By using the network namespace pointers as tags to separate out the the sysfs directory entries we ensure that we don't have conflicts in the directories and applications only see a limited set of the network devices. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | | | | | pipe: add support for shrinking and growing pipesJens Axboe2010-05-211-17/+21
| | |_|/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds F_GETPIPE_SZ and F_SETPIPE_SZ fcntl() actions for growing and shrinking the size of a pipe and adjusts pipe.c and splice.c (and relay and network splice) usage to work with these larger (or smaller) pipes. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* | | | | | net: fix sk_forward_alloc corruptionsEric Dumazet2010-05-291-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As David found out, sock_queue_err_skb() should be called with socket lock hold, or we risk sk_forward_alloc corruption, since we use non atomic operations to update this field. This patch adds bh_lock_sock()/bh_unlock_sock() pair to three spots. (BH already disabled) 1) skb_tstamp_tx() 2) Before calling ip_icmp_error(), in __udp4_lib_err() 3) Before calling ipv6_icmp_error(), in __udp6_lib_err() Reported-by: Anton Blanchard <anton@samba.org> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | | | | skb: make skb_recycle_check() return a bool valueChangli Gao2010-05-291-6/+6
| |_|_|_|/ |/| | | | | | | | | | | | | | | | | | | Signed-off-by: Changli Gao <xiaosuo@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | | | netlink: bug fix: wrong size was calculated for vfinfo list blobScott Feldman2010-05-281-5/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The wrong size was being calculated for vfinfo. In one case, it was over- calculating using nlmsg_total_size on attrs, in another case, it was under-calculating by assuming ifla_vf_* structs are packed together, but each struct is it's own attr w/ hdr (and padding). Signed-off-by: Scott Feldman <scofeldm@cisco.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | | | netlink: bug fix: don't overrun skbs on vf_port dumpScott Feldman2010-05-281-6/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Noticed by Patrick McHardy: was continuing to fill skb after a nla_put_failure, ignoring the size calculated by upper layer. Now, return -EMSGSIZE on any overruns, but also allow netdev to fail ndo_get_vf_port with error other than -EMSGSIZE, thus unwinding nest. Signed-off-by: Scott Feldman <scofeldm@cisco.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | | | net: fix __neigh_event_send()Eric Dumazet2010-05-281-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 7fee226ad23 (net: add a noref bit on skb dst) missed one spot where an skb is enqueued, with a possibly not refcounted dst entry. __neigh_event_send() inserts skb into arp_queue, so we must make sure dst entry is refcounted, or dst entry can be freed by garbage collector after caller exits from rcu protected section. Reported-by: Ingo Molnar <mingo@elte.hu> Tested-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | | | net: fix lock_sock_bh/unlock_sock_bhEric Dumazet2010-05-272-2/+37
| |_|/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This new sock lock primitive was introduced to speedup some user context socket manipulation. But it is unsafe to protect two threads, one using regular lock_sock/release_sock, one using lock_sock_bh/unlock_sock_bh This patch changes lock_sock_bh to be careful against 'owned' state. If owned is found to be set, we must take the slow path. lock_sock_bh() now returns a boolean to say if the slow path was taken, and this boolean is used at unlock_sock_bh time to call the appropriate unlock function. After this change, BH are either disabled or enabled during the lock_sock_bh/unlock_sock_bh protected section. This might be misleading, so we rename these functions to lock_sock_fast()/unlock_sock_fast(). Reported-by: Anton Blanchard <anton@samba.org> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Tested-by: Anton Blanchard <anton@samba.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | | tun: Update classid on packet injectionHerbert Xu2010-05-241-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch makes tun update its socket classid every time we inject a packet into the network stack. This is so that any updates made by the admin to the process writing packets to tun is effected. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | | cls_cgroup: Store classid in struct sockHerbert Xu2010-05-241-0/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Up until now cls_cgroup has relied on fetching the classid out of the current executing thread. This runs into trouble when a packet processing is delayed in which case it may execute out of another thread's context. Furthermore, even when a packet is not delayed we may fail to classify it if soft IRQs have been disabled, because this scenario is indistinguishable from one where a packet unrelated to the current thread is processed by a real soft IRQ. In fact, the current semantics is inherently broken, as a single skb may be constructed out of the writes of two different tasks. A different manifestation of this problem is when the TCP stack transmits in response of an incoming ACK. This is currently unclassified. As we already have a concept of packet ownership for accounting purposes in the skb->sk pointer, this is a natural place to store the classid in a persistent manner. This patch adds the cls_cgroup classid in struct sock, filling up an existing hole on 64-bit :) The value is set at socket creation time. So all sockets created via socket(2) automatically gains the ID of the thread creating it. Whenever another process touches the socket by either reading or writing to it, we will change the socket classid to that of the process if it has a valid (non-zero) classid. For sockets created on inbound connections through accept(2), we inherit the classid of the original listening socket through sk_clone, possibly preceding the actual accept(2) call. In order to minimise risks, I have not made this the authoritative classid. For now it is only used as a backup when we execute with soft IRQs disabled. Once we're completely happy with its semantics we can use it as the sole classid. Footnote: I have rearranged the error path on cls_group module creation. If we didn't do this, then there is a window where someone could create a tc rule using cls_group before the cgroup subsystem has been registered. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | | net-2.6 : V2 - fix dev_get_valid_nameDaniel Lezcano2010-05-231-8/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | the commit: commit d90310243fd750240755e217c5faa13e24f41536 Author: Octavian Purdila <opurdila@ixiacom.com> Date: Wed Nov 18 02:36:59 2009 +0000 net: device name allocation cleanups introduced a bug when there is a hash collision making impossible to rename a device with eth%d. This bug is very hard to reproduce and appears rarely. The problem is coming from we don't pass a temporary buffer to __dev_alloc_name but 'dev->name' which is modified by the function. A detailed explanation is here: http://marc.info/?l=linux-netdev&m=127417784011987&w=2 Changelog: V2 : replaced strings comparison by pointers comparison Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr> Reviewed-by: Octavian Purdila <opurdila@ixiacom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | | rtnetlink: Fix error handling in do_setlink()David Howells2010-05-231-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit c02db8c6290bb992442fec1407643c94cc414375: Author: Chris Wright <chrisw@sous-sol.org> Date: Sun May 16 01:05:45 2010 -0700 Subject: rtnetlink: make SR-IOV VF interface symmetric adds broken error handling to do_setlink() in net/core/rtnetlink.c. The problem is the following chunk of code: if (tb[IFLA_VFINFO_LIST]) { struct nlattr *attr; int rem; nla_for_each_nested(attr, tb[IFLA_VFINFO_LIST], rem) { if (nla_type(attr) != IFLA_VF_INFO) ----> goto errout; err = do_setvfinfo(dev, attr); if (err < 0) goto errout; modified = 1; } } which can get to errout without setting err, resulting in the following error: net/core/rtnetlink.c: In function 'do_setlink': net/core/rtnetlink.c:904: warning: 'err' may be used uninitialized in this function Change the code to return -EINVAL in this case. Note that this might not be the appropriate error though. Signed-off-by: David Howells <dhowells@redhat.com> cc: Chris Wright <chrisw@sous-sol.org> cc: David S. Miller <davem@davemloft.net> Acked-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | | net: fix problem in dequeuing from input_pkt_queueTom Herbert2010-05-211-13/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix some issues introduced in batch skb dequeuing for input_pkt_queue. The primary issue it that the queue head must be incremented only after a packet has been processed, that is only after __netif_receive_skb has been called. This is needed for the mechanism to prevent OOO packet in RFS. Also when flushing the input_pkt_queue and process_queue, the process queue should be done first to prevent OOO packets. Because the input_pkt_queue has been effectively split into two queues, the calculation of the tail ptr is no longer correct. The correct value would be head+input_pkt_queue->len+process_queue->len. To avoid this calculation we added an explict input_queue_tail in softnet_data. The tail value is simply incremented when queuing to input_pkt_queue. Signed-off-by: Tom Herbert <therbert@google.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | | gro: Fix bogus gso_size on the first fraglist entryHerbert Xu2010-05-201-0/+1
| |/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When GRO produces fraglist entries, and the resulting skb hits an interface that is incapable of TSO but capable of FRAGLIST, we end up producing a bogus packet with gso_size non-zero. This was reported in the field with older versions of KVM that did not set the TSO bits on tuntap. This patch fixes that. Reported-by: Igor Zhang <yugzhang@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | net: Add netlink support for virtual port management (was iovnl)Scott Feldman2010-05-171-1/+168
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add new netdev ops ndo_{set|get}_vf_port to allow setting of port-profile on a netdev interface. Extends netlink socket RTM_SETLINK/ RTM_GETLINK with two new sub msgs called IFLA_VF_PORTS and IFLA_PORT_SELF (added to end of IFLA_cmd list). These are both nested atrtibutes using this layout: [IFLA_NUM_VF] [IFLA_VF_PORTS] [IFLA_VF_PORT] [IFLA_PORT_*], ... [IFLA_VF_PORT] [IFLA_PORT_*], ... ... [IFLA_PORT_SELF] [IFLA_PORT_*], ... These attributes are design to be set and get symmetrically. VF_PORTS is a list of VF_PORTs, one for each VF, when dealing with an SR-IOV device. PORT_SELF is for the PF of the SR-IOV device, in case it wants to also have a port-profile, or for the case where the VF==PF, like in enic patch 2/2 of this patch set. A port-profile is used to configure/enable the external switch virtual port backing the netdev interface, not to configure the host-facing side of the netdev. A port-profile is an identifier known to the switch. How port- profiles are installed on the switch or how available port-profiles are made know to the host is outside the scope of this patch. There are two types of port-profiles specs in the netlink msg. The first spec is for 802.1Qbg (pre-)standard, VDP protocol. The second spec is for devices that run a similar protocol as VDP but in firmware, thus hiding the protocol details. In either case, the specs have much in common and makes sense to define the netlink msg as the union of the two specs. For example, both specs have a notition of associating/deassociating a port-profile. And both specs require some information from the hypervisor manager, such as client port instance ID. The general flow is the port-profile is applied to a host netdev interface using RTM_SETLINK, the receiver of the RTM_SETLINK msg communicates with the switch, and the switch virtual port backing the host netdev interface is configured/enabled based on the settings defined by the port-profile. What those settings comprise, and how those settings are managed is again outside the scope of this patch, since this patch only deals with the first step in the flow. Signed-off-by: Scott Feldman <scofeldm@cisco.com> Signed-off-by: Roopa Prabhu <roprabhu@cisco.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | net: Remove unnecessary semicolons after switch statementsJoe Perches2010-05-171-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | Also added an explicit break; to avoid a fallthrough in net/ipv4/tcp_input.c Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | net: add a noref bit on skb dstEric Dumazet2010-05-173-1/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use low order bit of skb->_skb_dst to tell dst is not refcounted. Change _skb_dst to _skb_refdst to make sure all uses are catched. skb_dst() returns the dst, regardless of noref bit set or not, but with a lockdep check to make sure a noref dst is not given if current user is not rcu protected. New skb_dst_set_noref() helper to set an notrefcounted dst on a skb. (with lockdep check) skb_dst_drop() drops a reference only if skb dst was refcounted. skb_dst_force() helper is used to force a refcount on dst, when skb is queued and not anymore RCU protected. Use skb_dst_force() in __sk_add_backlog(), __dev_xmit_skb() if !IFF_XMIT_DST_RELEASE or skb enqueued on qdisc queue, in sock_queue_rcv_skb(), in __nf_queue(). Use skb_dst_force() in dev_requeue_skb(). Note: dst_use_noref() still dirties dst, we might transform it later to do one dirtying per jiffies. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | rps: avoid one atomic in enqueue_to_backlogEric Dumazet2010-05-171-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If CONFIG_SMP=y, then we own a queue spinlock, we can avoid the atomic test_and_set_bit() from napi_schedule_prep(). We now have same number of atomic ops per netif_rx() calls than with pre-RPS kernel. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | Merge branch 'master' of ↵David S. Miller2010-05-161-49/+110
|\ \ \ | | |/ | |/| | | | | | | | | | | | | master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: include/linux/if_link.h
| * | rtnetlink: make SR-IOV VF interface symmetricChris Wright2010-05-161-49/+110
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now we have a set of nested attributes: IFLA_VFINFO_LIST (NESTED) IFLA_VF_INFO (NESTED) IFLA_VF_MAC IFLA_VF_VLAN IFLA_VF_TX_RATE This allows a single set to operate on multiple attributes if desired. Among other things, it means a dump can be replayed to set state. The current interface has yet to be released, so this seems like something to consider for 2.6.34. Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | net: Introduce sk_route_nocapsEric Dumazet2010-05-161-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | TCP-MD5 sessions have intermittent failures, when route cache is invalidated. ip_queue_xmit() has to find a new route, calls sk_setup_caps(sk, &rt->u.dst), destroying the sk->sk_route_caps &= ~NETIF_F_GSO_MASK that MD5 desperately try to make all over its way (from tcp_transmit_skb() for example) So we send few bad packets, and everything is fine when tcp_transmit_skb() is called again for this socket. Since ip_queue_xmit() is at a lower level than TCP-MD5, I chose to use a socket field, sk_route_nocaps, containing bits to mask on sk_route_caps. Reported-by: Bhaskar Dutta <bhaskie@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | net: Consistent skb timestampingEric Dumazet2010-05-152-19/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With RPS inclusion, skb timestamping is not consistent in RX path. If netif_receive_skb() is used, its deferred after RPS dispatch. If netif_rx() is used, its done before RPS dispatch. This can give strange tcpdump timestamps results. I think timestamping should be done as soon as possible in the receive path, to get meaningful values (ie timestamps taken at the time packet was delivered by NIC driver to our stack), even if NAPI already can defer timestamping a bit (RPS can help to reduce the gap) Tom Herbert prefer to sample timestamps after RPS dispatch. In case sampling is expensive (HPET/acpi_pm on x86), this makes sense. Let admins switch from one mode to another, using a new sysctl, /proc/sys/net/core/netdev_tstamp_prequeue Its default value (1), means timestamps are taken as soon as possible, before backlog queueing, giving accurate timestamps. Setting a 0 value permits to sample timestamps when processing backlog, after RPS dispatch, to lower the load of the pre-RPS cpu. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | net: adjust handle_macvlan to pass port struct to hookJiri Pirko2010-05-151-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now there's null check here and also again in the hook. Looking at bridge bits which are simmilar, port structure is rcu_dereferenced right away in handle_bridge and passed to hook. Looks nicer. Signed-off-by: Jiri Pirko <jpirko@redhat.com> Acked-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | Merge branch 'master' of ↵David S. Miller2010-05-121-6/+5
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: Documentation/feature-removal-schedule.txt drivers/net/wireless/ath/ar9170/usb.c drivers/scsi/iscsi_tcp.c net/ipv4/ipmr.c
| * | veth: Dont kfree_skb() after dev_forward_skb()Eric Dumazet2010-05-061-6/+5
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In case of congestion, netif_rx() frees the skb, so we must assume dev_forward_skb() also consume skb. Bug introduced by commit 445409602c092 (veth: move loopback logic to common location) We must change dev_forward_skb() to always consume skb, and veth to not double free it. Bug report : http://marc.info/?l=linux-netdev&m=127310770900442&w=3 Reported-by: Martín Ferrari <martin.ferrari@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | rps: Various optimizationsEric Dumazet2010-05-061-6/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce ____napi_schedule() helper for callers in irq disabled contexts. rps_trigger_softirq() becomes a leaf function. Use container_of() in process_backlog() instead of accessing per_cpu address. Use a custom inlined version of __napi_complete() in process_backlog() to avoid one locked instruction : only current cpu owns and manipulates this napi, and NAPI_STATE_SCHED is the only possible flag set on backlog. we can use a plain write instead of clear_bit(), and we dont need an smp_mb() memory barrier, since RPS is on, backlog is protected by a spinlock. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | netpoll: add generic support for bridge and bonding devicesWANG Cong2010-05-061-5/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This whole patchset is for adding netpoll support to bridge and bonding devices. I already tested it for bridge, bonding, bridge over bonding, and bonding over bridge. It looks fine now. To make bridge and bonding support netpoll, we need to adjust some netpoll generic code. This patch does the following things: 1) introduce two new priv_flags for struct net_device: IFF_IN_NETPOLL which identifies we are processing a netpoll; IFF_DISABLE_NETPOLL is used to disable netpoll support for a device at run-time; 2) introduce one new method for netdev_ops: ->ndo_netpoll_cleanup() is used to clean up netpoll when a device is removed. 3) introduce netpoll_poll_dev() which takes a struct net_device * parameter; export netpoll_send_skb() and netpoll_poll_dev() which will be used later; 4) hide a pointer to struct netpoll in struct netpoll_info, ditto. 5) introduce ->real_dev for struct netpoll. 6) introduce a new status NETDEV_BONDING_DESLAE, which is used to disable netconsole before releasing a slave, to avoid deadlocks. Cc: David Miller <davem@davemloft.net> Cc: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: WANG Cong <amwang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>