linux/net
Willy Tarreau bad115cfe5 tcp: do_tcp_sendpages() must try to push data out on oom conditions
Since recent changes on TCP splicing (starting with commits 2f533844
"tcp: allow splice() to build full TSO packets" and 35f9c09f "tcp:
tcp_sendpages() should call tcp_push() once"), I started seeing
massive stalls when forwarding traffic between two sockets using
splice() when pipe buffers were larger than socket buffers.

Latest changes (net: netdev_alloc_skb() use build_skb()) made the
problem even more apparent.

The reason seems to be that if do_tcp_sendpages() fails on out of memory
condition without being able to send at least one byte, tcp_push() is not
called and the buffers cannot be flushed.

After applying the attached patch, I cannot reproduce the stalls at all
and the data rate it perfectly stable and steady under any condition
which previously caused the problem to be permanent.

The issue seems to have been there since before the kernel migrated to
git, which makes me think that the stalls I occasionally experienced
with tux during stress-tests years ago were probably related to the
same issue.

This issue was first encountered on 3.0.31 and 3.2.17, so please backport
to -stable.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Acked-by: Eric Dumazet <edumazet@google.com>
Cc: <stable@vger.kernel.org>
2012-05-17 18:31:43 -04:00
..
9p net/9p: handle flushed Tclunk/Tremove 2012-02-26 14:49:57 -06:00
802 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-04-02 17:53:39 -07:00
8021q Revert "net: maintain namespace isolation between vlan and real device" 2012-05-10 23:03:34 -04:00
appletalk net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules 2011-10-31 19:30:30 -04:00
atm Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
ax25 net ax25: Reorder ax25_exit to remove races. 2012-04-19 15:37:48 -04:00
batman-adv Merge tag 'batman-adv-for-davem' of git://git.open-mesh.org/linux-merge 2012-03-11 15:36:34 -07:00
bluetooth Bluetooth: mgmt: Fix device_connected sending order 2012-05-14 13:56:15 -04:00
bridge set fake_rtable's dst to NULL to avoid kernel Oops 2012-04-24 00:16:24 -04:00
caif caif: Fix memory leakage in the chnl_net.c. 2012-04-13 11:01:44 -04:00
can can: remove references to berlios mailinglist 2011-10-17 19:22:46 -04:00
ceph libceph: isolate kmap() call in write_partial_msg_pages() 2012-03-22 10:47:52 -05:00
core pktgen: fix crash at module unload 2012-05-10 23:10:24 -04:00
dcb net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules 2011-10-31 19:30:30 -04:00
dccp dccp: fix bug in sequence number validation during connection setup 2012-03-03 09:02:52 -07:00
decnet Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
dns_resolver KEYS: Allow special keyrings to be cleared 2012-01-19 14:38:51 +11:00
dsa dsa: Move switch drivers to new directory drivers/net/dsa 2011-11-29 00:21:36 -05:00
econet Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
ethernet Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
ieee802154 6lowpan: add missing spin_lock_init() 2012-04-26 05:32:55 -04:00
ipv4 tcp: do_tcp_sendpages() must try to push data out on oom conditions 2012-05-17 18:31:43 -04:00
ipv6 tcp: fix TCP_MAXSEG for established IPv6 passive sockets 2012-04-22 17:09:35 -04:00
ipx net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules 2011-10-31 19:30:30 -04:00
irda Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
iucv Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2012-03-22 18:15:32 -07:00
key net/key/af_key.c: add missing kfree_skb 2012-04-13 11:01:44 -04:00
l2tp net: l2tp: unlock socket lock before returning from l2tp_ip_sendmsg 2012-05-02 21:04:33 -04:00
lapb Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
llc llc: Fix race condition in llc_ui_recvmsg 2012-01-24 15:33:19 -05:00
mac80211 mac80211: fix AP mode EAP tx for VLAN stations 2012-04-30 14:40:05 -04:00
netfilter netfilter: ipset: fix hash size checking in kernel 2012-05-16 15:38:49 -04:00
netlabel netlabel: use GFP flags from caller instead of GFP_ATOMIC 2012-03-22 19:29:57 -04:00
netlink netlink: fix races after skb queueing 2012-04-06 04:21:06 -04:00
netrom Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
nfc NFC: Fix the LLCP Tx fragmentation loop 2012-04-11 15:09:33 -04:00
openvswitch openvswitch: checking wrong variable in queue_userspace_packet() 2012-05-13 15:47:34 -04:00
packet Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
phonet phonet: Sort out initiailziation and cleanup code. 2012-04-13 11:01:43 -04:00
rds RDS: use gfp flags from caller in conn_alloc() 2012-03-22 19:29:58 -04:00
rfkill device.h: cleanup users outside of linux/include (C files) 2012-03-11 14:27:37 -04:00
rose Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-04-02 17:53:39 -07:00
rxrpc RxRPC: Fix kcalloc parameters swapped 2012-02-14 14:41:55 -05:00
sched netem: fix possible skb leak 2012-05-01 13:40:48 -04:00
sctp sctp: check cached dst before using it 2012-05-10 23:15:47 -04:00
sunrpc auth_gss: the list of pseudoflavors not being parsed correctly 2012-05-03 12:35:33 -04:00
tipc tipc: Optimize setting of immutable payload message header fields 2012-02-29 11:45:35 -05:00
unix poll: add poll_requested_events() and poll_does_not_wait() functions 2012-03-23 16:58:38 -07:00
wanrouter wanrouter: Remove kernel_lock annotations 2011-11-07 13:27:30 -05:00
wimax net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules 2011-10-31 19:30:30 -04:00
wireless cfg80211: fix interface combinations check. 2012-04-13 14:05:35 -04:00
x25 net:x25: use IS_ENABLED 2011-12-16 15:49:52 -05:00
xfrm xfrm: Access the replay notify functions via the registered callbacks 2012-03-22 19:29:58 -04:00
compat.c Merge branch 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-03-29 18:12:23 -07:00
Kconfig net: Add Open vSwitch kernel components. 2011-12-03 09:35:17 -08:00
Makefile net: Add Open vSwitch kernel components. 2011-12-03 09:35:17 -08:00
nonet.c
socket.c tcp: tcp_sendpages() should call tcp_push() once 2012-04-05 19:04:27 -04:00
sysctl_net.c sysctl: Modify __register_sysctl_paths to take a set instead of a root and an nsproxy 2012-01-24 16:40:30 -08:00