Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6

* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (867 commits)
  [SKY2]: status polling loop (post merge)
  [NET]: Fix NAPI completion handling in some drivers.
  [TCP]: Limit processing lost_retrans loop to work-to-do cases
  [TCP]: Fix lost_retrans loop vs fastpath problems
  [TCP]: No need to re-count fackets_out/sacked_out at RTO
  [TCP]: Extract tcp_match_queue_to_sack from sacktag code
  [TCP]: Kill almost unused variable pcount from sacktag
  [TCP]: Fix mark_head_lost to ignore R-bit when trying to mark L
  [TCP]: Add bytes_acked (ABC) clearing to FRTO too
  [IPv6]: Update setsockopt(IPV6_MULTICAST_IF) to support RFC 3493, try2
  [NETFILTER]: x_tables: add missing ip6t_modulename aliases
  [NETFILTER]: nf_conntrack_tcp: fix connection reopening
  [QETH]: fix qeth_main.c
  [NETLINK]: fib_frontend build fixes
  [IPv6]: Export userland ND options through netlink (RDNSS support)
  [9P]: build fix with !CONFIG_SYSCTL
  [NET]: Fix dev_put() and dev_hold() comments
  [NET]: make netlink user -> kernel interface synchronious
  [NET]: unify netlink kernel socket recognition
  [NET]: cleanup 3rd argument in netlink_sendskb
  ...

Fix up conflicts manually in Documentation/feature-removal-schedule.txt
and my new least favourite crap, the "mod_devicetable" support in the
files include/linux/mod_devicetable.h and scripts/mod/file2alias.c.

(The latter files seem to be explicitly _designed_ to get conflicts when
different subsystems work with them - that have an absolutely horrid
lack of subsystem separation!)

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 99 insertions, 0 deletions

diff --git a/Documentation/networking/netconsole.txt b/Documentation/networking/netconsole.txt
index 1caa6c73469..3c2f2b32863 100644
--- a/Documentation/networking/netconsole.txt
+++ b/Documentation/networking/netconsole.txt
@@ -3,6 +3,10 @@ started by Ingo Molnar <mingo@redhat.com>, 2001.09.17
 2.6 port and netpoll api by Matt Mackall <mpm@selenic.com>, Sep 9 2003
 
 Please send bug reports to Matt Mackall <mpm@selenic.com>
+and Satyam Sharma <satyam.sharma@gmail.com>
+
+Introduction:
+=============
 
 This module logs kernel printk messages over UDP allowing debugging of
 problem where disk logging fails and serial consoles are impractical.
@@ -13,6 +17,9 @@ the specified interface as soon as possible. While this doesn't allow
 capture of early kernel panics, it does capture most of the boot
 process.
 
+Sender and receiver configuration:
+==================================
+
 It takes a string configuration parameter "netconsole" in the
 following format:
 
@@ -34,21 +41,113 @@ Examples:
 
  insmod netconsole netconsole=@/,@10.0.0.2/
 
+It also supports logging to multiple remote agents by specifying
+parameters for the multiple agents separated by semicolons and the
+complete string enclosed in "quotes", thusly:
+
+ modprobe netconsole netconsole="@/,@10.0.0.2/;@/eth1,6892@10.0.0.3/"
+
 Built-in netconsole starts immediately after the TCP stack is
 initialized and attempts to bring up the supplied dev at the supplied
 address.
 
 The remote host can run either 'netcat -u -l -p <port>' or syslogd.
 
+Dynamic reconfiguration:
+========================
+
+Dynamic reconfigurability is a useful addition to netconsole that enables
+remote logging targets to be dynamically added, removed, or have their
+parameters reconfigured at runtime from a configfs-based userspace interface.
+[ Note that the parameters of netconsole targets that were specified/created
+from the boot/module option are not exposed via this interface, and hence
+cannot be modified dynamically. ]
+
+To include this feature, select CONFIG_NETCONSOLE_DYNAMIC when building the
+netconsole module (or kernel, if netconsole is built-in).
+
+Some examples follow (where configfs is mounted at the /sys/kernel/config
+mountpoint).
+
+To add a remote logging target (target names can be arbitrary):
+
+ cd /sys/kernel/config/netconsole/
+ mkdir target1
+
+Note that newly created targets have default parameter values (as mentioned
+above) and are disabled by default -- they must first be enabled by writing
+"1" to the "enabled" attribute (usually after setting parameters accordingly)
+as described below.
+
+To remove a target:
+
+ rmdir /sys/kernel/config/netconsole/othertarget/
+
+The interface exposes these parameters of a netconsole target to userspace:
+
+	enabled		Is this target currently enabled?	(read-write)
+	dev_name	Local network interface name		(read-write)
+	local_port	Source UDP port to use			(read-write)
+	remote_port	Remote agent's UDP port			(read-write)
+	local_ip	Source IP address to use		(read-write)
+	remote_ip	Remote agent's IP address		(read-write)
+	local_mac	Local interface's MAC address		(read-only)
+	remote_mac	Remote agent's MAC address		(read-write)
+
+The "enabled" attribute is also used to control whether the parameters of
+a target can be updated or not -- you can modify the parameters of only
+disabled targets (i.e. if "enabled" is 0).
+
+To update a target's parameters:
+
+ cat enabled				# check if enabled is 1
+ echo 0 > enabled			# disable the target (if required)
+ echo eth2 > dev_name			# set local interface
+ echo 10.0.0.4 > remote_ip		# update some parameter
+ echo cb:a9:87:65:43:21 > remote_mac	# update more parameters
+ echo 1 > enabled			# enable target again
+
+You can also update the local interface dynamically. This is especially
+useful if you want to use interfaces that have newly come up (and may not
+have existed when netconsole was loaded / initialized).
+
+Miscellaneous notes:
+====================
+
 WARNING: the default target ethernet setting uses the broadcast
 ethernet address to send packets, which can cause increased load on
 other systems on the same ethernet segment.
 
+TIP: some LAN switches may be configured to suppress ethernet broadcasts
+so it is advised to explicitly specify the remote agents' MAC addresses
+from the config parameters passed to netconsole.
+
+TIP: to find out the MAC address of, say, 10.0.0.2, you may try using:
+
+ ping -c 1 10.0.0.2 ; /sbin/arp -n | grep 10.0.0.2
+
+TIP: in case the remote logging agent is on a separate LAN subnet than
+the sender, it is suggested to try specifying the MAC address of the
+default gateway (you may use /sbin/route -n to find it out) as the
+remote MAC address instead.
+
 NOTE: the network device (eth1 in the above case) can run any kind
 of other network traffic, netconsole is not intrusive. Netconsole
 might cause slight delays in other traffic if the volume of kernel
 messages is high, but should have no other impact.
 
+NOTE: if you find that the remote logging agent is not receiving or
+printing all messages from the sender, it is likely that you have set
+the "console_loglevel" parameter (on the sender) to only send high
+priority messages to the console. You can change this at runtime using:
+
+ dmesg -n 8
+
+or by specifying "debug" on the kernel command line at boot, to send
+all kernel messages to the console. A specific value for this parameter
+can also be set using the "loglevel" kernel boot option. See the
+dmesg(8) man page and Documentation/kernel-parameters.txt for details.
+
 Netconsole was designed to be as instantaneous as possible, to
 enable the logging of even the most critical kernel bugs. It works
 from IRQ contexts as well, and does not enable interrupts while