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Michael Brown 926816c58f [efi] Pad transmit buffer length to work around vendor driver bugs 
The Mellanox/Nvidia UEFI driver is built from the same codebase as the
iPXE driver, and appears to contain the bug that was fixed in commit
c11734e ("[golan] Use ETH_HLEN for inline header size").  This results
in identical failures when using the SNP or NII interface (via
e.g. snponly.efi) to drive a Mellanox card while EAPoL is enabled.

Work around the underlying UEFI driver bug by padding transmit I/O
buffers to the minimum Ethernet frame length before passing them to
the underlying driver's transmit function.

This padding is not technically necessary, since almost all modern
hardware will insert transmit padding as necessary (and where the
hardware does not support doing so, the underlying UEFI driver is
responsible for adding any necessary padding).  However, it is
guaranteed to be harmless (other than a miniscule performance impact):
the Ethernet specification requires zero padding up to the minimum
frame length for packets that are transmitted onto the wire, and so
the receiver will see the same packet whether or not we manually
insert this padding in software.

The additional padding causes the underlying Mellanox driver to avoid
its faulty code path, since it will never be asked to transmit a very
short packet.

Tested-by: Eric Hagberg <ehagberg@janestreet.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
 		2024-03-18 22:52:05 +00:00
.github/workflows [ci] Update action versions to silence GitHub warnings 2024-03-07 23:25:35 +00:00
contrib [cloud] Add utility script to read iPXE output from INT13CON partition 2023-11-07 18:05:45 +00:00
src [efi] Pad transmit buffer length to work around vendor driver bugs 2024-03-18 22:52:05 +00:00
COPYING [legal] Update GPLv2 licence text 2015-02-26 17:59:53 +00:00
COPYING.GPLv2 [legal] Update GPLv2 licence text 2015-02-26 17:59:53 +00:00
COPYING.UBDL [legal] Add support for the Unmodified Binary Distribution Licence 2015-03-02 12:07:14 +00:00
README [doc] Re-add README file 2010-05-28 00:03:47 +01:00

README 

iPXE README File

Quick start guide:

   cd src
   make

For any more detailed instructions, see http://ipxe.org