user/sven/linux.git/drivers/net/loopback.c, branch v3.18.48

net: better IFF_XMIT_DST_RELEASE support

2014-10-07T17:22:11Z

Testing xmit_more support with netperf and connected UDP sockets, I found strange dst refcount false sharing. Current handling of IFF_XMIT_DST_RELEASE is not optimal. Dropping dst in validate_xmit_skb() is certainly too late in case packet was queued by cpu X but dequeued by cpu Y The logical point to take care of drop/force is in __dev_queue_xmit() before even taking qdisc lock. As Julian Anastasov pointed out, need for skb_dst() might come from some packet schedulers or classifiers. This patch adds new helper to cleanly express needs of various drivers or qdiscs/classifiers. Drivers that need skb_dst() in their ndo_start_xmit() should call following helper in their setup instead of the prior : dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; -> netif_keep_dst(dev); Instead of using a single bit, we use two bits, one being eventually rebuilt in bonding/team drivers. The other one, is permanent and blocks IFF_XMIT_DST_RELEASE being rebuilt in bonding/team. Eventually, we could add something smarter later. Signed-off-by: Eric Dumazet Cc: Julian Anastasov Signed-off-by: David S. Miller

net: set name_assign_type in alloc_netdev()

2014-07-15T23:12:48Z

Extend alloc_netdev{,_mq{,s}}() to take name_assign_type as argument, and convert all users to pass NET_NAME_UNKNOWN. Coccinelle patch: @@ expression sizeof_priv, name, setup, txqs, rxqs, count; @@ ( -alloc_netdev_mqs(sizeof_priv, name, setup, txqs, rxqs) +alloc_netdev_mqs(sizeof_priv, name, NET_NAME_UNKNOWN, setup, txqs, rxqs) | -alloc_netdev_mq(sizeof_priv, name, setup, count) +alloc_netdev_mq(sizeof_priv, name, NET_NAME_UNKNOWN, setup, count) | -alloc_netdev(sizeof_priv, name, setup) +alloc_netdev(sizeof_priv, name, NET_NAME_UNKNOWN, setup) ) v9: move comments here from the wrong commit Signed-off-by: Tom Gundersen Reviewed-by: David Herrmann Signed-off-by: David S. Miller

net: Replace u64_stats_fetch_begin_bh to u64_stats_fetch_begin_irq

2014-03-15T02:41:36Z

Replace the bh safe variant with the hard irq safe variant. We need a hard irq safe variant to deal with netpoll transmitting packets from hard irq context, and we need it in most if not all of the places using the bh safe variant. Except on 32bit uni-processor the code is exactly the same so don't bother with a bh variant, just have a hard irq safe variant that everyone can use. Signed-off-by: "Eric W. Biederman" Signed-off-by: David S. Miller

loopback: sctp: add NETIF_F_SCTP_CSUM to device features

2014-02-25T00:00:08Z

Drivers are allowed to set NETIF_F_SCTP_CSUM if they have hardware crc32c checksumming support for the SCTP protocol. Currently, NETIF_F_SCTP_CSUM flag is available in igb, ixgbe, i40e/i40evf drivers and for vlan devices. If we don't have NETIF_F_SCTP_CSUM then crc32c is done through CPU instructions, invoked from crypto layer, or if not available as slow-path fallback in software. Currently, loopback device propagates checksum offloading feature flags in dev->features, but is missing SCTP checksum offloading. Therefore, account for NETIF_F_SCTP_CSUM as well. Before patch: ./netperf_sctp -H 192.168.0.100 -t SCTP_STREAM_MANY SCTP 1-TO-MANY STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.0.100 () port 0 AF_INET Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 4194304 4194304 4096 10.00 4683.50 After patch: ./netperf_sctp -H 192.168.0.100 -t SCTP_STREAM_MANY SCTP 1-TO-MANY STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.0.100 () port 0 AF_INET Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 4194304 4194304 4096 10.00 15348.26 Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller

net: introduce netdev_alloc_pcpu_stats() for drivers

2014-02-14T20:49:55Z

There are many drivers calling alloc_percpu() to allocate pcpu stats and then initializing ->syncp. So just introduce a helper function for them. Cc: David S. Miller Signed-off-by: Cong Wang Signed-off-by: David S. Miller

net: allow setting mac address of loopback device

2014-02-13T22:46:49Z

We are trying to mirror the local traffic from lo to eth0, allowing setting mac address of lo to eth0 would make the ether addresses in these packets correct, so that we don't have to modify the ether header again. Since usually no one cares about its mac address (all-zero), it is safe to allow those who care to set its mac address. Cc: Hannes Frederic Sowa Cc: Neil Horman Cc: Stephen Hemminger Cc: Eric Dumazet Cc: David S. Miller Signed-off-by: Cong Wang Acked-by: Neil Horman Signed-off-by: David S. Miller

drivers/net: delete non-required instances of include

2014-01-16T19:53:26Z

None of these files are actually using any __init type directives and hence don't need to include . Most are just a left over from __devinit and __cpuinit removal, or simply due to code getting copied from one driver to the next. This covers everything under drivers/net except for wireless, which has been submitted separately. Signed-off-by: Paul Gortmaker Signed-off-by: David S. Miller

net: Explicitly initialize u64_stats_sync structures for lockdep

2013-11-06T11:40:25Z

In order to enable lockdep on seqcount/seqlock structures, we must explicitly initialize any locks. The u64_stats_sync structure, uses a seqcount, and thus we need to introduce a u64_stats_init() function and use it to initialize the structure. This unfortunately adds a lot of fairly trivial initialization code to a number of drivers. But the benefit of ensuring correctness makes this worth while. Because these changes are required for lockdep to be enabled, and the changes are quite trivial, I've not yet split this patch out into 30-some separate patches, as I figured it would be better to get the various maintainers thoughts on how to best merge this change along with the seqcount lockdep enablement. Feedback would be appreciated! Signed-off-by: John Stultz Acked-by: Julian Anastasov Signed-off-by: Peter Zijlstra Cc: Alexey Kuznetsov Cc: "David S. Miller" Cc: Eric Dumazet Cc: Hideaki YOSHIFUJI Cc: James Morris Cc: Jesse Gross Cc: Mathieu Desnoyers Cc: "Michael S. Tsirkin" Cc: Mirko Lindner Cc: Patrick McHardy Cc: Roger Luethi Cc: Rusty Russell Cc: Simon Horman Cc: Stephen Hemminger Cc: Steven Rostedt Cc: Thomas Petazzoni Cc: Wensong Zhang Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/1381186321-4906-2-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar

net loopback: Set loopback_dev to NULL when freed

2013-09-17T23:05:13Z

It has recently turned up that we have a number of long standing bugs in the network stack cleanup code with use of the loopback device after it has been freed that have not turned up because in most cases the storage allocated to the loopback device is not reused, when those accesses happen. Set looback_dev to NULL to trigger oopses instead of silent data corrupt when we hit this class of bug. Signed-off-by: "Eric W. Biederman" Acked-by: Eric Dumazet Signed-off-by: David S. Miller

net: loopback: fix a dst refcounting issue

2013-01-27T06:30:35Z

Ben Greear reported crashes in ip_rcv_finish() on a stress test involving many macvlans. We tracked the bug to a dst use after free. ip_rcv_finish() was calling dst->input() and got garbage for dst->input value. It appears the bug is in loopback driver, lacking a skb_dst_force() before calling netif_rx(). As a result, a non refcounted dst, normally protected by a RCU read_lock section, was escaping this section and could be freed before the packet being processed. [] loopback_xmit+0x64/0x83 [] dev_hard_start_xmit+0x26c/0x35e [] dev_queue_xmit+0x2c4/0x37c [] ? dev_hard_start_xmit+0x35e/0x35e [] ? eth_header+0x28/0xb6 [] neigh_resolve_output+0x176/0x1a7 [] ip_finish_output2+0x297/0x30d [] ? ip_finish_output2+0x137/0x30d [] ip_finish_output+0x63/0x68 [] ip_output+0x61/0x67 [] dst_output+0x17/0x1b [] ip_local_out+0x1e/0x23 [] ip_queue_xmit+0x315/0x353 [] ? ip_send_unicast_reply+0x2cc/0x2cc [] tcp_transmit_skb+0x7ca/0x80b [] tcp_connect+0x53c/0x587 [] ? getnstimeofday+0x44/0x7d [] ? ktime_get_real+0x11/0x3e [] tcp_v4_connect+0x3c2/0x431 [] __inet_stream_connect+0x84/0x287 [] ? inet_stream_connect+0x22/0x49 [] ? _local_bh_enable_ip+0x84/0x9f [] ? local_bh_enable+0xd/0x11 [] ? lock_sock_nested+0x6e/0x79 [] ? inet_stream_connect+0x22/0x49 [] inet_stream_connect+0x33/0x49 [] sys_connect+0x75/0x98 This bug was introduced in linux-2.6.35, in commit 7fee226ad2397b (net: add a noref bit on skb dst) skb_dst_force() is enforced in dev_queue_xmit() for devices having a qdisc. Reported-by: Ben Greear Signed-off-by: Eric Dumazet Tested-by: Ben Greear Signed-off-by: David S. Miller