Syslinux - Jun 2015 - EFI: PXE: "My IP is 0.0.0.0"

Hello Gene,

thanks a lot for your patch! It doesn't work yet, but I have some more
information.

Before the patch, the boot sequence ended with the following:
  NBP file download successfully.
Getting cached packet
My IP is 0.0.0.0

After the patch it ended with the following (note that the IP is the same
as the Station IP address):
  NBP file download successfully.
LibLocateHandle returned nr 8
Handle [0] gave -3 00000000
Handle [1] gave -3 00000000
Handle [2] gave 0 0ad402a7
Getting cached packet
My IP is 10.212.2.167

Greetings,


Sebastian

On Sun, Jun 21, 2015 at 8:48 PM, Gene Cumm via Syslinux <syslinux at
zytor.com>
wrote:
> On Sat, Jun 20, 2015 at 5:09 PM, Gene Cumm <gene.cumm at gmail.com>
wrote:
> > Starting a new thread for the moment and BCCing the two reporters of
the
> issue.
> >
> > Looking over the code, I think I finally see why we get junk data from
> > the PXE base.  If we tell the PXE base that a buffer is 0 bytes long,
> > we should expect junk/null data.
> >
> > I'm hoping to have a patch for testing over the weekend.  If
either of
> > you would rather start a bug on the bugzilla, feel free.
>
> Attached are a patch and a limited set of test binaries.  Patch is
> relative to 38e861eb.  This should give more indication to the EFI PXE
> "My IP is 0.0.0.0" issue.
>
> --
> -Gene
>
> _______________________________________________
> Syslinux mailing list
> Submissions to Syslinux at zytor.com
> Unsubscribe or set options at:
> http://www.zytor.com/mailman/listinfo/syslinux
>

Ady2 suggested to me on IRC to add additional information to the ML.

With BIOS P89 v1.32 (03/05/2015) I saw errors from core_udp_sendto:
Getting cached packet
My IP is 0.0.0.0
core_udp_sendto: stalling on configure with no mapping
core_udp_sendto: stalling on configure with no mapping
core_udp_sendto: stalling on configure with no mapping
core_udp_sendto: stalling on configure with no mapping
core_udp_sendto: stalling on configure with no mapping

With BIOS P89 v1.40 (05/06/2015) I don't see any errors from
core_udp_sendto anymore.

Hardware used: HP ProLiant DL380 Gen9
NIC being used: NIC1 (not NIC0, since that's connected to a different
network)

Greetings,



Sebastian

On Mon, Jun 22, 2015 at 8:54 AM, S. Schauenburg <s.schauenburg at
gmail.com>
wrote:
> Hello Gene,
>
> thanks a lot for your patch! It doesn't work yet, but I have some more
> information.
>
> Before the patch, the boot sequence ended with the following:
>   NBP file download successfully.
> Getting cached packet
> My IP is 0.0.0.0
>
> After the patch it ended with the following (note that the IP is the same
> as the Station IP address):
>   NBP file download successfully.
> LibLocateHandle returned nr 8
> Handle [0] gave -3 00000000
> Handle [1] gave -3 00000000
> Handle [2] gave 0 0ad402a7
> Getting cached packet
> My IP is 10.212.2.167
>
> Greetings,
>
>
> Sebastian
>
> On Sun, Jun 21, 2015 at 8:48 PM, Gene Cumm via Syslinux <
> syslinux at zytor.com> wrote:
>
>> On Sat, Jun 20, 2015 at 5:09 PM, Gene Cumm <gene.cumm at
gmail.com> wrote:
>> > Starting a new thread for the moment and BCCing the two reporters
of
>> the issue.
>> >
>> > Looking over the code, I think I finally see why we get junk data
from
>> > the PXE base.  If we tell the PXE base that a buffer is 0 bytes
long,
>> > we should expect junk/null data.
>> >
>> > I'm hoping to have a patch for testing over the weekend.  If
either of
>> > you would rather start a bug on the bugzilla, feel free.
>>
>> Attached are a patch and a limited set of test binaries.  Patch is
>> relative to 38e861eb.  This should give more indication to the EFI PXE
>> "My IP is 0.0.0.0" issue.
>>
>> --
>> -Gene
>>
>> _______________________________________________
>> Syslinux mailing list
>> Submissions to Syslinux at zytor.com
>> Unsubscribe or set options at:
>> http://www.zytor.com/mailman/listinfo/syslinux
>>
>
>

On Mon, Jun 22, 2015 at 6:03 AM, S. Schauenburg <s.schauenburg at
gmail.com> wrote:
> Ady2 suggested to me on IRC to add additional information to the ML.
>
> With BIOS P89 v1.32 (03/05/2015) I saw errors from core_udp_sendto:
> Getting cached packet
> My IP is 0.0.0.0
> core_udp_sendto: stalling on configure with no mapping
> core_udp_sendto: stalling on configure with no mapping
> core_udp_sendto: stalling on configure with no mapping
> core_udp_sendto: stalling on configure with no mapping
> core_udp_sendto: stalling on configure with no mapping
>
> With BIOS P89 v1.40 (05/06/2015) I don't see any errors from
core_udp_sendto
> anymore.
But you still see the "My IP is 0.0.0.0"?  The firmware version change
is definitely useful.  Without this, I would have considered the
stalling messages as expected.
> Hardware used: HP ProLiant DL380 Gen9
> NIC being used: NIC1 (not NIC0, since that's connected to a different
> network)
This is definitely useful and I suspect the major reason for the issue.

> On Mon, Jun 22, 2015 at 8:54 AM, S. Schauenburg <s.schauenburg at
gmail.com>
> wrote:
>>
>> Hello Gene,
>>
>> thanks a lot for your patch! It doesn't work yet, but I have some
more
>> information.
Excellent!  I figured that if I didn't have a solution, the temporary
extra Print() calls should at least provide more details, which they
did.  I was surprised to see that your server returns 8 protocol
handles (likely IPv4 and IPv6 for each of the 4 NIC ports).
>> Before the patch, the boot sequence ended with the following:
>>   NBP file download successfully.
>> Getting cached packet
>> My IP is 0.0.0.0
>>
>> After the patch it ended with the following (note that the IP is the
same
>> as the Station IP address):
>>   NBP file download successfully.
>> LibLocateHandle returned nr 8
>> Handle [0] gave -3 00000000
>> Handle [1] gave -3 00000000
>> Handle [2] gave 0 0ad402a7
>> Getting cached packet
>> My IP is 10.212.2.167
I'd guess that the ARP packets are being seen on NIC0 and not NIC1.
I'm hoping to have another patch this week.
>> On Sun, Jun 21, 2015 at 8:48 PM, Gene Cumm via Syslinux
>> <syslinux at zytor.com> wrote:
>>>
>>> On Sat, Jun 20, 2015 at 5:09 PM, Gene Cumm <gene.cumm at
gmail.com> wrote:
>>> > Starting a new thread for the moment and BCCing the two
reporters of
>>> > the issue.
>>> >
>>> > Looking over the code, I think I finally see why we get junk
data from
>>> > the PXE base.  If we tell the PXE base that a buffer is 0
bytes long,
>>> > we should expect junk/null data.
>>> >
>>> > I'm hoping to have a patch for testing over the weekend. 
If either of
>>> > you would rather start a bug on the bugzilla, feel free.
>>>
>>> Attached are a patch and a limited set of test binaries.  Patch is
>>> relative to 38e861eb.  This should give more indication to the EFI
PXE
>>> "My IP is 0.0.0.0" issue.
>>>
>>> --
>>> -Gene
>>>
>>> _______________________________________________
>>> Syslinux mailing list
>>> Submissions to Syslinux at zytor.com
>>> Unsubscribe or set options at:
>>> http://www.zytor.com/mailman/listinfo/syslinux
>>
>>
>


-- 
-Gene

> With BIOS P89 v1.32 (03/05/2015) I saw errors from core_udp_sendto:
> Getting cached packet
> My IP is 0.0.0.0
> core_udp_sendto: stalling on configure with no mapping
> core_udp_sendto: stalling on configure with no mapping
> core_udp_sendto: stalling on configure with no mapping
> core_udp_sendto: stalling on configure with no mapping
> core_udp_sendto: stalling on configure with no mapping
> 
> With BIOS P89 v1.40 (05/06/2015) I don't see any errors from
> core_udp_sendto anymore.
> 
> Hardware used: HP ProLiant DL380 Gen9
> NIC being used: NIC1 (not NIC0, since that's connected to a different
> network)
 
Thank you.

Users having problems with booting (with any bootloader) should always 
check firmware updates availability.

In some cases, testing and providing feedback before updating the 
firmware might actually help in narrowing down the source of a problem, 
especially when a firmware downgrade is not supported. The reported 
results are indeed helpful.

Just to give a hint / sense of the importance of updating BIOS / UEFI 
firmware, I am listing here the latest fixes and the full revision 
history of the firmware updates for the HP ProLiant DL380 Gen9/DL360 
Gen9 (P89) Servers (which has been mentioned several times here in the 
Syslinux Mailing List during the last few months).

Both lists show issues related to NICs, USB, serial console, 
keyboard...

Regards,
Ady.


Latest fixes (15 Jun 2015):

 *** *** 

Addressed an issue where the platform may become unresponsive during 
system boot when the server is configured for Legacy Boot Mode and the 
USB Boot Support has been disabled.

Addressed an issue where the Intel NIC DMA Channels (IOAT) option could 
not be properly be configured from the Embedded UEFI Shell via the 
Sysconfig command.

Addressed an issue where the +/- keys in the BIOS/Platform 
Configuration (RBSU) Boot Options menu were not functioning properly 
when configuring the server through a BIOS Serial Console Session.

Addressed an issue where the fwupdate Embedded UEFI Shell command and 
the Firmware Update pre-boot application could hang during a firmware 
update and not successfully flash the device.

Addressed an issue where the server may fail to boot properly to a 
Windows Deployment Server (WDS) when configured for IPv6 network boot 
mode.

Addressed an issue where an optional PCIe adapter's legacy Expansion 
ROM may not run properly or the Expansion ROM's Setup Utility may not 
run properly when the server is configured for Legacy Boot Mode. This 
issue was seen with a Seagate storage adapter but may impact other 
devices. 

Addressed an issue where the Administrator Password would not be 
properly configured from the Embedded UEFI Shell Sysconfig command.

Addressed an issue where a system could become unresponsive when 
booting to Linux Operating when serial output was enabled from the 
operating system and the iLO Virtual Serial Port was the only enabled 
UART.

Addressed various issues with webclient and ftp commands in the 
Embedded UEFI Shell.

Addressed an issue in which an Interphase audio streaming PCI-express 
expansion card may not achieve optimal performance resulting in dropped 
packets when streaming data. A similar issue could be seen with other 
PCI-express expansion cards implemented with a PCI device behind a PLX 
PCIe-to-PCI bridge. This type of PCI-express card implementation is 
more common with older PCI-express expansion cards.

Addressed an issue where the system may experience a Linux kernel panic 
when booting from a SATA optical drive attached to the embedded SATA 
controller when the SATA controller is configured for Dynamic Smart 
Array B140i support.

Addressed an issue where the system health LED would remain blinking 
RED (indicating a failed state) due to a power supply failure after the 
power supply had been replaced. Once the power supply is replaced, the 
system health LED should have returned to the blinking GREEN state. 
With previous revisions of the System ROM, the system health LED would 
not return to GREEN until after a reboot when a failed power supply is 
replaced.

Addressed an issue where the system health LED would remain blinking 
AMBER (indicating a degraded state) due to an installed power supply 
not being plugged in after the power supply had been plugged in. Once 
the power supply is plugged in, the system health LED should have 
returned to the blinking GREEN state. With previous revisions of the 
System ROM, the system health LED would not return to GREEN until after 
a reboot when an unplugged power supply is plugged in.

Addressed an issue where a system may become unresponsive when 
launching a guest operating system under a Hypervisor operating system 
such as Citrix or VMware when VT-d is enabled. This issue is NOT unique 
to HP servers.

Addressed a possible issue where the platform may become unresponsive 
during POST when the user selects the Simplified Chinese language in 
System Utilities.


 *** *** 


Revision History:

 *** *** 

Version: 1.40_05-06-2015 (15 Jun 2015) 
Enhancements

Added a Server Security BIOS/Platform Configuration (RBSU) option to 
Enable or Disable "Processor AES-NI Support". This option enables or 
disables the Advanced Encryption Standard Instruction Set. The option 
is enabled by default and was enabled automatically with previous 
revisions of the BIOS.

Added support for UEFI iSCSI Software Initiator boot functionality. The 
iSCSI Software Initiator boot support can be enabled on any network 
card that is in Ethernet mode. The iSCSI network settings can be 
configured in the new System Utilities BIOS/Platform Configuration 
(RBSU) iSCSI Boot Configuration menu, as well as using the HP RESTful 
API HpiScsiSoftwareInititiator resource type. This option is only 
available in UEFI Boot Mode.

Added a BIOS/Platform Configuration (RBSU) Network Option for VLAN 
Configuration. This option allows the user to configure Virtual LAN 
(VLAN) settings for all network devices present in the system. This 
option is only available in UEFI Boot Mode.

Added a new System Utilities Embedded Applications Active Health System 
Log option. This option allows users to download Active Health System 
(AHS) Logs. 

Added support for additional Storage Options to BIOS/Platform 
Configuration (RBSU). These new options allow the user to configure the 
number of boot targets that are listed per storage controller in the 
UEFI Boot Order. This option can be used to limit the number of boot 
targets to simplify the UEFI boot order and decrease boot time. These 
options are only available in UEFI Boot Mode.

Added pre-boot OHCI USB support. This will allow an optional PCIe USB 
controller, such as available on the Teradici PCoIP Zero Client card, 
to be functional in a pre-boot environment. This also adds support for 
booting from USB devices attached to optional PCIe OHCI USB 
controllers. Support for OHCI USB controllers should be available from 
operating system drivers when not in the pre-boot environment.

Added support for a new partitions command in the Embedded UEFI Shell. 
This command can be used to view all available drive partitions.

Added support for a new ahsdownload command in the Embedded UEFI Shell. 
This command can be used to download Active Health System (AHS) files.

Added support for a new restclient command in the Embedded UEFI Shell. 
This command can be used to configure the server through the HP RESTful 
services.

Updated the HP RESTful API HP BIOS Attribute Registry resources to 
match the latest BIOS/Platform Configuration options.

Updated the HPRESTful API support to report and set the default UEFI 
Boot Order settings using the HpServerBootOrder resource type.

Updated the language translations (non-English modes) for System 
Utilities.

Updated the HP RESTful API support for HpBios resource to rename 
"SecureBoot" property to "SecureBootStatus" to avoid
conflict with the
"SecureBoot" property in HpSecureBoot resource. This change will
impact
any scripts written with a dependency on the "SecureBoot" property in 
the HpBios resource.

Updated the System Utilities BIOS/Platform Configuration (RBSU) Fibre 
Channel/FCoE Scan Policy option to default to Scan Configured Targets 
only. Previous revisions of the System ROM defaulted to scanning all 
targets.

Enhanced the thermal solution to provide proper cooling for optional 
PCIe graphics and acceleration cards.

Enhanced the System Utilities System Information and the Embedded UEFI 
Shell sysinfo command to provide additional details for the processor, 
memory, PCI subsections. In addition, added a new Firmware Information 
menu to System Information to provide a list of current firmware 
revisions for supported components.

Reduced boot time when the Dynamic Smart Array B140i RAID is enabled.


  *** 

Version: 1.32_03-05-2015 (B) (13 May 2015) 
Enhancements

Enhanced the thermal solution to provide proper cooling for optional 
PCIe graphics and acceleration cards.


  *** 

Version: 1.30_12-24-2014 (10 Apr 2015) 
Enhancements/New Features:

Added support for a Generic USB Boot entry in the UEFI Boot Order list. 
This new entry is used as a place holder for any USB device that is 
bootable in UEFI. The user can set the boot priority of this Generic 
USB Boot entry, and retain this priority for use with USB devices that 
might be installed in the future. Attempting to boot from the Generic 
USB Boot entry will result in attempting all UEFI bootable USB devices 
that are available in the system. The user can still control the 
priority of the boot entries of individual USB devices in the UEFI Boot 
Order list. This new Generic USB Boot entry will now be visible by 
default in the UEFI Boot Order after updating to this System ROM 
release. This new option is applicable only in UEFI Boot Mode and might 
be configured from the HP RESTful API or the System Utilities 
BIOS/Platform Configuration (RBSU). Note: The system will attempt to 
boot all UEFI bootable USB devices in the order of the Generic USB Boot 
entry even if installed individual USB devices are configured lower in 
the boot order.

Added a new System Utilities BIOS/Platform Configuration (RBSU) Fibre 
Channel/FCoE Scan Policy menu that allows the user to select how the 
UEFI BIOS will scan for valid Fibre Channel (or boot from SAN) boot 
targets. By default, the system will now only scan for Fibre Channel 
boot targets that are configured in each adapter. In the past, the 
system would scan for all Fibre Channel or FCoE available targets, 
potentially resulting in long boot times and large number of entries in 
the UEFI Boot Order list. The boot targets for adapters can be 
configured using the adapter specific menu in the System Utilities, 
System Configuration menu, or using management software such as HP 
Virtual Connect or HP OneView. This setting is applicable only in UEFI 
Boot Mode. A firmware update of the fibre channel controller might also 
be required to take full advantage of this feature.

Added a new System Utilities BIOS/Platform Configuration (RBSU) NUMA 
Group Size Optimizations menu that allows the user to select how the 
platform will report processor grouping to the operating system. For 
some applications which cannot optimally handle high logical processor 
counts that are optimally divided into smaller groups, it might be 
necessary to change the default setting to get optimal performance.

Added a new System Utilities BIOS/Platform Configuration (RBSU) I/O 
Non-Posted Prefetching performance option that allows the user to 
configure how the chipset balances I/O traffic for PCI-e devices. 
Disabling this option has been shown to provide performance benefits in 
a very small subset of configurations including certain Infiniband 
configurations that require a balanced mix of read and write traffic as 
well as configurations with multiple x16 devices that utilize the max 
bandwidth of the PCI-e bus. Since disabling the option also has a 
negative impact on maximum I/O read bandwidth, the overwhelming 
majority of configurations will benefit from leaving this option at the 
default.

Added support for Memory Mirroring Mode. This option can be selected 
from the Advanced Memory Protection Mode selection. This option 
provides enhanced memory availability and resiliency but requires 
additional memory be installed to achieve the same amount of memory 
available to the operating system.

Added support for loading the Embedded UEFI Shell Auto-Startup script 
from the network in addition to physical/virtual media. The URL 
describing the network (HTTP or FTP) location of the startup script can 
be configured in the System Utilities /Platform Configuration (RBSU), 
under the Embedded Shell menu. This allows for using the Embedded UEFI 
Shell as a scriptable deployment environment without the need for 
physical or virtual media (on a bare metal system).

Added support to Standard Format Output (SFO) to the SysConfig command 
in the Embedded UEFI Shell. This allows for easier parsing of the 
command output using Shell scripts.

Added support for boot from URL (HTTP or FTP) functionality in UEFI 
Boot Mode. The network settings (DHCP or static IP) and boot file URL 
can be configured in the new System Utilities BIOS/Platform 
Configuration (RBSU) Pre-Boot Network settings menu. The file can 
either be a UEFI Network Boot Program (NBP), or an ISO image containing 
a UEFI bootable OS image. The Boot from ISO support is currently 
limited to operating systems that have a self contained OS image (such 
as WinPE, mini Linux, or VMware ESX installer). Booting Windows or 
Linux OS installation media is currently not supported.

Added support for a webclient command in the Embedded UEFI Shell. The 
command can be used to download files from HTTP and FTP servers. It can 
also be used to download ISO CD/DVD images and mount them in memory as 
RAM disks.

Added support for an FTP command in the Embedded UEFI Shell. The 
command can be used to download and upload files to/from FTP servers.

Added support for a Compress command in the Embedded UEFI Shell. The 
command can be used to compress and decompress ZIP files.

Added support for a SecBoot command in the Embedded UEFI Shell. The 
command can be used to display the Secure Boot keys and certificates.

Enhanced the RamDisk command in the Embedded UEFI Shell to support 
FAT32 RAM disks, increasing the disk size limit from 512 MB to 2GB.

Added support for the HP Dual 8GB MicroSD EM USB Kit. This device can 
be plugged into the internal USB port on the server to allow a mirrored 
MicroSD card solution.

Added support to configure the BIOS Serial Console Baud Rate to 38400 
from the System Utilities BIOS/Platform Configuration (RBSU).

Added a new System Utilities BIOS/Platform Configuration (RBSU) 
Internal SD Card Slot menu located in USB Options that allows the user 
to disable boot from the embedded SD card.

Added support for Intel Trusted eXecution Technology (TXT).

Updated OpenSSL support to version 0.9.8zb to address potential issues 
that might impact the UEFI Secure Boot support.

Updated the HP RESTful API HP BIOS Attribute Registry resources to 
match the latest BIOS/Platform Configuration options.

Updated the HP RESTful API HpBiosAttributeRegistrySchema to version 
1.2.0, adding support for BIOS Attributes of type "Password". Also 
added a new GrayOut property that can be used to describe some 
dependency scenarios. Also updated enumDescriptions of all enum 
definitions in the schema.

Updated the HP RESTful API HpBios, HpServerBootSettings, 
HpBiosMappsings schemas to version 1.1.0. Added support for self-links 
in these resources.

Updated the language translations (non-English modes) for System 
Utilities.

Updated help documentation for System Utilities and the Embedded UEFI 
Shell.

Increased timeout values in Embedded UEFI Shell IfConfig command to 
reduce the chances of network DHCP configuration failing due to 
timeouts caused by delays on the network or slow response when trying 
to contact the DHCP server.

Enhanced the UEFI Exception handler to provide extended debug and trace 
information when in a pre-OS environment.

Known Issues:

None


  *** 

Version: 1.32_03-05-2015 (6 Apr 2015) 
Enhancements

Enhanced the thermal solution to provide proper cooling for optional 
PCIe graphics and acceleration cards.


  *** 

Version: 1.21_11-03-2014 (19 Dec 2014) 
Enhancements

 None


  *** 

Version: 1.20_08-26-2014 (14 Oct 2014) 
Enhancements

Added support for the HP Dynamic Smart Array B140i to allow the user to 
launch 
the HP Smart Storage Administrator (HPSSA) application from the System 
Utilities menu. 

Updated the HP RESTful API resources of type 
HpBiosAttributeRegistrySchema to 
schema version 1.1.0, adding additional meta-data for Immutable and 
Write-Only 
BIOS attributes.

Updated the language translations (non-English modes) for System 
Utilities.

Updated help documentation for System Utilities and the UEFI Embedded 
Shell.

Updated the HpBiosAttributeRegistry resources to match the latest 
BIOS/Platform 
Configuration options.


  *** 

Version: 1.00_07-11-2014 (17 Sep 2014) 
Enhancements

 *** ***

On Mon, Jun 22, 2015 at 2:54 AM, S. Schauenburg <s.schauenburg at
gmail.com> wrote:
> Hello Gene,
>
> thanks a lot for your patch! It doesn't work yet, but I have some more
> information.
>
> Before the patch, the boot sequence ended with the following:
>   NBP file download successfully.
> Getting cached packet
> My IP is 0.0.0.0
>
> After the patch it ended with the following (note that the IP is the same
as
> the Station IP address):
>   NBP file download successfully.
> LibLocateHandle returned nr 8
> Handle [0] gave -3 00000000
> Handle [1] gave -3 00000000
> Handle [2] gave 0 0ad402a7
> Getting cached packet
> My IP is 10.212.2.167
>
> Greetings,
>
>
> Sebastian
>
> On Sun, Jun 21, 2015 at 8:48 PM, Gene Cumm via Syslinux <syslinux at
zytor.com>
> wrote:
>>
>> On Sat, Jun 20, 2015 at 5:09 PM, Gene Cumm <gene.cumm at
gmail.com> wrote:
>> > Starting a new thread for the moment and BCCing the two reporters
of the
>> > issue.
>> >
>> > Looking over the code, I think I finally see why we get junk data
from
>> > the PXE base.  If we tell the PXE base that a buffer is 0 bytes
long,
>> > we should expect junk/null data.
>> >
>> > I'm hoping to have a patch for testing over the weekend.  If
either of
>> > you would rather start a bug on the bugzilla, feel free.
>>
>> Attached are a patch and a limited set of test binaries.  Patch is
>> relative to 38e861eb.  This should give more indication to the EFI PXE
>> "My IP is 0.0.0.0" issue.
Looks like the patch mostly addresses the initial search to find the
right handle for PXE.  I think I found the remaining source of the
issue (the part that's generating the handle->Configure() messages).
I'm trying to read through pieces of the EFI spec, gnu-efi API, and a
few other sources.  I'm pretty certain you'll see that the previous
patch/binaries are sending packets that _should_ be sent on NIC1 out
NIC0.

-- 
-Gene

>>> 
 Looks like the patch mostly addresses the
 initial search to find the right handle for
 PXE.? I think I found the remaining source of the
 issue (the part that's generating the
 handle->Configure() messages).
 I'm trying to read through pieces of the EFI spec, gnu-efi API,
 and a few other sources.? I'm pretty
 certain you'll see that the previous
 patch/binaries are sending packets that
 _should_ be sent on NIC1 out
 NIC0.-- 
 -Gene
<<<

Hi Gene
have you seen this thread?
http://www.syslinux.org/archives/2015-April/023436.html
continued here
http://www.syslinux.org/archives/2015-May/023443.html

Cao's patch try to solve the same multi-NIC issue you are dealing with;

Your approach detect's the right NIC at 
pxe.c\net_parse_dhcp(void)
but it is also necessary to detect the right NIC again at 
main.c\efi_create_binding()
as explained here.
http://www.syslinux.org/archives/2015-May/023453.html
Cao's patch fails doing this because it relies on certain assumptions on 
handle "order" that are not correct.

I'm also trying to fix this bug but unfortunately I'm not having much
time.
This is the approach I'm going to try: 
1) detecting the right NIC at pxe.c\net_parse_dhcp(void) (as you do)
2) saving its associated MAC address.
3) at main.c\efi_create_binding()    (let's consider the UDP case)
LibLocateHandle() returns the handles of the devices that publish a EFI
UDPv4 Service Binding Protocol GUID. Each device with a published EFI UDPv4 
Service Binding Protocol GUID supports the EFI UDPv4 Protocol and may be
available for use.
Considering a "Device Path Protocol" is attached to device handles
then
I think parsing the Path Protocol of each returned handle we can detect the 
"MAC Address Device Path" structure and get the associated MAC
address.
The returned handle that has a MAC address matching the one previously saved at
pxe.c\net_parse_dhcp(void) should be the one that has to be used creating a
child of
EFI UDPv4 Protocol.

I'm looking for a simpler way to do this but so far I haven't found it.

Best,
Patrick