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2012-07-10net: Fix (nearly-)kernel-doc comments for various functionsBen Hutchings
Fix incorrect start markers, wrapped summary lines, missing section breaks, incorrect separators, and some name mismatches. Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-30net: introduce new priv_flag indicating iface capable of change mac when runningJiri Pirko
Introduce IFF_LIVE_ADDR_CHANGE priv_flag and use it to disable netif_running() check in eth_mac_addr() Signed-off-by: Jiri Pirko <jpirko@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-10net, drivers/net: Convert compare_ether_addr_64bits to ether_addr_equal_64bitsJoe Perches
Use the new bool function ether_addr_equal_64bits to add some clarity and reduce the likelihood for misuse of compare_ether_addr_64bits for sorting. Done via cocci script: $ cat compare_ether_addr_64bits.cocci @@ expression a,b; @@ - !compare_ether_addr_64bits(a, b) + ether_addr_equal_64bits(a, b) @@ expression a,b; @@ - compare_ether_addr_64bits(a, b) + !ether_addr_equal_64bits(a, b) @@ expression a,b; @@ - !ether_addr_equal_64bits(a, b) == 0 + ether_addr_equal_64bits(a, b) @@ expression a,b; @@ - !ether_addr_equal_64bits(a, b) != 0 + !ether_addr_equal_64bits(a, b) @@ expression a,b; @@ - ether_addr_equal_64bits(a, b) == 0 + !ether_addr_equal_64bits(a, b) @@ expression a,b; @@ - ether_addr_equal_64bits(a, b) != 0 + ether_addr_equal_64bits(a, b) @@ expression a,b; @@ - !!ether_addr_equal_64bits(a, b) + ether_addr_equal_64bits(a, b) Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-15net: cleanup unsigned to unsigned intEric Dumazet
Use of "unsigned int" is preferred to bare "unsigned" in net tree. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-03-28Remove all #inclusions of asm/system.hDavid Howells
Remove all #inclusions of asm/system.h preparatory to splitting and killing it. Performed with the following command: perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *` Signed-off-by: David Howells <dhowells@redhat.com>
2012-02-13eth: reset addr_assign_type if eth_mac_addr() calledDanny Kukawka
If eth_mac_addr() get called, usually if SIOCSIFHWADDR was used to change the MAC of a ethernet device, reset the addr_assign_type to NET_ADDR_PERM if the state was NET_ADDR_RANDOM before. Reset the state since the MAC is no longer random at least not from the kernel side. v2: changed to bitops, removed if() Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-09-15net: don't clear IFF_XMIT_DST_RELEASE in ether_setupnhorman
d88733150 introduced the IFF_SKB_TX_SHARING flag, which I unilaterally set in ether_setup. In doing this I didn't realize that other flags (such as IFF_XMIT_DST_RELEASE) might be set prior to calling the ether_setup routine. This patch changes ether_setup to or in SKB_TX_SHARING so as not to inadvertently clear other existing flags. Thanks to Pekka Riikonen for pointing out my error Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Pekka Riikonen <priikone@iki.fi> CC: "David S. Miller" <davem@davemloft.net> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-27net: add IFF_SKB_TX_SHARED flag to priv_flagsNeil Horman
Pktgen attempts to transmit shared skbs to net devices, which can't be used by some drivers as they keep state information in skbs. This patch adds a flag marking drivers as being able to handle shared skbs in their tx path. Drivers are defaulted to being unable to do so, but calling ether_setup enables this flag, as 90% of the drivers calling ether_setup touch real hardware and can handle shared skbs. A subsequent patch will audit drivers to ensure that the flag is set properly Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Jiri Pirko <jpirko@redhat.com> CC: Robert Olsson <robert.olsson@its.uu.se> CC: Eric Dumazet <eric.dumazet@gmail.com> CC: Alexey Dobriyan <adobriyan@gmail.com> CC: David S. Miller <davem@davemloft.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-25net: fix eth.c kernel-doc warningRandy Dunlap
From: Randy Dunlap <rdunlap@xenotime.net> Fix new kernel-doc warning in eth.c: Warning(net/ethernet/eth.c:237): No description found for parameter 'type' Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-13net: Push protocol type directly down to header_ops->cache()David S. Miller
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-12eth: fix new kernel-doc warningRandy Dunlap
Fix new kernel-doc warning (copy-paste typo): Warning(net/ethernet/eth.c:366): No description found for parameter 'rxqs' Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-10net: Add alloc_netdev_mqs functionTom Herbert
Added alloc_netdev_mqs function which allows the number of transmit and receive queues to be specified independenty. alloc_netdev_mq was changed to a macro to call the new function. Also added alloc_etherdev_mqs with same purpose. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-23net: return operator cleanupEric Dumazet
Change "return (EXPR);" to "return EXPR;" return is not a function, parentheses are not required. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-08-26net: use scnprintf() to avoid potential buffer overflowChangli Gao
strlcpy() returns the total length of the string they tried to create, so we should not use its return value without any check. scnprintf() returns the number of characters written into @buf not including the trailing '\0', so use it instead here. Signed-off-by: Changli Gao <xiaosuo@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-14Net: ethernet: pe2.c: fix EXPORT_SYMBOL macro code style issueChihau Chau
This patch fix a code style issue, if a function is exported, the EXPORT_SYMBOL macro for it should follow immediately after the closing function brace line. Signed-off-by: Chihau Chau <chihau@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-10net-next: remove useless union keywordChangli Gao
remove useless union keyword in rtable, rt6_info and dn_route. Since there is only one member in a union, the union keyword isn't useful. Signed-off-by: Changli Gao <xiaosuo@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-02net: Inline skb_pull() in eth_type_trans().David S. Miller
In commit 6be8ac2f ("[NET]: uninline skb_pull, de-bloats a lot") we uninlined skb_pull. But in some critical paths it makes sense to inline this thing and it helps performance significantly. Create an skb_pull_inline() so that we can do this in a way that serves also as annotation. Based upon a patch by Eric Dumazet. Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-21ethernet: print protocol in host byte orderJohannes Berg
Eric's recent patch added __force, but this place would seem to require actually doing a byte order conversion so the printk is consistent across architectures. Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-20net: Fix various endianness glitchesEric Dumazet
Sparse can help us find endianness bugs, but we need to make some cleanups to be able to more easily spot real bugs. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2009-12-26llc: use dev_hard_headerOctavian Purdila
Using dev_hard_header allows us to use LLC with VLANs and potentially other Ethernet/TokernRing specific encapsulations. It also removes code duplication between LLC and Ethernet/TokenRing core code. Signed-off-by: Octavian Purdila <opurdila@ixiacom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-15remove deprecated and not used: print_mac()Marin Mitov
The function print_mac in net/ethernet/eth.c is marked __deprecated and not used. Remove it. Signed-off-by: Marin Mitov <mitov@issp.bas.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-25net: remove COMPAT_NET_DEV_OPSAlexander Beregalov
All drivers are already converted to new net_device_ops API and nobody uses old API anymore. Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-23eth: Declare an optimized compare_ether_addr_64bits() functionEric Dumazet
Linus mentioned we could try to perform long word operations, even on potentially unaligned addresses, on x86 at least. David mentioned the HAVE_EFFICIENT_UNALIGNED_ACCESS test to handle this on all arches that have efficient unailgned accesses. I tried this idea and got nice assembly on 32 bits: 158: 33 82 38 01 00 00 xor 0x138(%edx),%eax 15e: 33 8a 34 01 00 00 xor 0x134(%edx),%ecx 164: c1 e0 10 shl $0x10,%eax 167: 09 c1 or %eax,%ecx 169: 74 0b je 176 <eth_type_trans+0x87> And very nice assembly on 64 bits of course (one xor, one shl) Nice oprofile improvement in eth_type_trans(), 0.17 % instead of 0.41 %, expected since we remove 8 instructions on a fast path. This patch implements a compare_ether_addr_64bits() function, that uses the CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS ifdef to efficiently perform the 6 bytes comparison on all capable arches. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-19netdev: expose ethernet address primitivesStephen Hemminger
When ethernet devices are converted, the function pointer setup by eth_setup() need to be done during intialization. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-08dsa: add support for Trailer tagging formatLennert Buytenhek
This adds support for the Trailer switch tagging format. This is another tagging that doesn't explicitly mark tagged packets with a distinct ethertype, so that we need to add a similar hack in the receive path as for the Original DSA tagging format. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Tested-by: Byron Bradley <byron.bbradley@gmail.com> Tested-by: Tim Ellis <tim.ellis@mac.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-08dsa: add support for original DSA tagging formatLennert Buytenhek
Most of the DSA switches currently in the field do not support the Ethertype DSA tagging format that one of the previous patches added support for, but only the original DSA tagging format. The original DSA tagging format carries the same information as the Ethertype DSA tagging format, but with the difference that it does not have an ethertype field. In other words, when receiving a packet that is tagged with an original DSA tag, there is no way of telling in eth_type_trans() that this packet is in fact a DSA-tagged packet. This patch adds a hook into eth_type_trans() which is only compiled in if support for a switch chip that doesn't support Ethertype DSA is selected, and which checks whether there is a DSA switch driver instance attached to this network device which uses the old tag format. If so, it sets the protocol field to ETH_P_DSA without looking at the packet, so that the packet ends up in the right place. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Tested-by: Nicolas Pitre <nico@marvell.com> Tested-by: Peter van Valderen <linux@ddcrew.com> Tested-by: Dirk Teurlings <dirk@upexia.nl> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-09-20net: Use hton[sl]() instead of __constant_hton[sl]() where applicableArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-13[NET]: Return more appropriate error from eth_validate_addr().Patrick McHardy
Paul Bolle wrote: > http://bugzilla.kernel.org/show_bug.cgi?id=9923 would have been much easier to > track down if eth_validate_addr() would somehow complain aloud if an address > is invalid. Shouldn't it make at least some noise? I guess it should return -EADDRNOTAVAIL similar to eth_mac_addr() when validation fails. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[ETH]: Combine format_addr() with print_mac().Michael Chan
print_mac() used many most net drivers and format_addr() used by net-sysfs.c are very similar and they can be intergrated. format_addr() is also identically redefined in the qla4xxx iscsi driver. Export a new function sysfs_format_mac() to be used by net-sysfs, qla4xxx and others in the future. Both print_mac() and sysfs_format_mac() call _format_mac_addr() to do the formatting. Changed print_mac() to use unsigned char * to be consistent with net_device struct's dev_addr. Added buffer length overrun checking as suggested by Joe Perches. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-23[NET]: Validate device addr prior to interface-upJeff Garzik
Signed-off-by: Jeff Garzik <jgarzik@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: Move hardware header operations out of netdevice.Stephen Hemminger
Since hardware header operations are part of the protocol class not the device instance, make them into a separate object and save memory. Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: Wrap hard_header_parseStephen Hemminger
Wrap the hard_header_parse function to simplify next step of header_ops conversion. Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: Wrap netdevice hardware header creation.Stephen Hemminger
Add inline for common usage of hardware header creation, and fix bug in IPV6 mcast where the assumption about negative return is an errno. Negative return from hard_header means not enough space was available,(ie -N bytes). Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: Introduce and use print_mac() and DECLARE_MAC_BUF()Joe Perches
This is nicer than the MAC_FMT stuff. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET] ethernet: optimize memcpy and memsetStephen Hemminger
The ethernet header management only needs to handle a fixed size address (6 bytes). If the memcpy/memset are changed to be passed a constant length, then compiler can optimize for this case (and if it is smart eliminate string instructions). Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-11[ETH]: Validate address in eth_mac_addrPatrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10[CORE] Stack changes to add multiqueue hardware support APIPeter P Waskiewicz Jr
Add the multiqueue hardware device support API to the core network stack. Allow drivers to allocate multiple queues and manage them at the netdev level if they choose to do so. Added a new field to sk_buff, namely queue_mapping, for drivers to know which tx_ring to select based on OS classification of the flow. Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[SK_BUFF]: Introduce skb_reset_mac_header(skb)Arnaldo Carvalho de Melo
For the common, open coded 'skb->mac.raw = skb->data' operation, so that we can later turn skb->mac.raw into a offset, reducing the size of struct sk_buff in 64bit land while possibly keeping it as a pointer on 32bit. This one touches just the most simple case, next will handle the slightly more "complex" cases. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[ETH]: Make eth_type_trans set skb->dev like the other *_type_transArnaldo Carvalho de Melo
One less thing for drivers writers to worry about. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NET] ETHERNET: Use htons() where appropriate.YOSHIFUJI Hideaki
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-14[PATCH] remove many unneeded #includes of sched.hTim Schmielau
After Al Viro (finally) succeeded in removing the sched.h #include in module.h recently, it makes sense again to remove other superfluous sched.h includes. There are quite a lot of files which include it but don't actually need anything defined in there. Presumably these includes were once needed for macros that used to live in sched.h, but moved to other header files in the course of cleaning it up. To ease the pain, this time I did not fiddle with any header files and only removed #includes from .c-files, which tend to cause less trouble. Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha, arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig, allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all configs in arch/arm/configs on arm. I also checked that no new warnings were introduced by the patch (actually, some warnings are removed that were emitted by unnecessarily included header files). Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-10[NET] ETHERNET: Fix whitespace errors.YOSHIFUJI Hideaki
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02[NET]: Kill direct includes of asm/checksum.hAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-28[NET]: Annotate dst_ops protocolAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[ETH]: indentation and cleanupStephen Hemminger
Run ethernet support through Lindent and fix up. Applies after docbook comments patch Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[ETH]: docbook commentsStephen Hemminger
Add docbook style comments to ethernet support. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-05[NET]: Eliminate unused /proc/sys/net/ethernetJes Sorensen
The /proc/sys/net/ethernet directory has been sitting empty for more than 10 years! Time to eliminate it! Signed-off-by: Jes Sorensen <jes@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-02-23[NET] ethernet: Fix first packet goes out with MAC 00:00:00:00:00:00Jamal Hadi Salim
When you turn off ARP on a netdevice then the first packet always goes out with a dstMAC of all zeroes. This is because the first packet is used to resolve ARP entries. Even though the ARP entry may be resolved (I tried by setting a static ARP entry for a host i was pinging from), it gets overwritten by virtue of having the netdevice disabling ARP. Subsequent packets go out fine with correct dstMAC address (which may be why people have ignored reporting this issue). To cut the story short: the culprit code is in net/ethernet/eth.c::eth_header() ---- /* * Anyway, the loopback-device should never use this function... */ if (dev->flags & (IFF_LOOPBACK|IFF_NOARP)) { memset(eth->h_dest, 0, dev->addr_len); return ETH_HLEN; } if(daddr) { memcpy(eth->h_dest,daddr,dev->addr_len); return ETH_HLEN; } ---- Note how the h_dest is being reset when device has IFF_NOARP. As a note: All devices including loopback pass a daddr. loopback in fact passes a 0 all the time ;-> This means i can delete the check totaly or i can remove the IFF_NOARP Alexey says: -------------------- I think, it was me who did this crap. It was so long ago I do not remember why it was made. I remember some troubles with dummy device. It tried to resolve addresses, apparently, without success and generated errors instead of blackholing. I think the problem was eventually solved at neighbour level. After some thinking I suspect the deletion of this chunk could change behaviour of some parts which do not use neighbour cache f.e. packet socket. I think safer approach would be to move this chunk after if (daddr). And the possibility to remove this completely could be analyzed later. -------------------- Patch updated with Alexey's safer suggestions. Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca> Acked-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Signed-off-by: David S. Miller <davem@davemloft.net>