IPoIB has a link-layer broadcast address that varies according to the
partition key. We currently go through several contortions to pretend
that the link-layer address is a fixed constant; by making the
broadcast address a property of the network device rather than the
link-layer protocol it will be possible to simplify IPoIB's broadcast
handling.
Move the icky call to step() from aoe.c to ata.c; this takes it at
least one step further away from where it really doesn't belong.
Unfortunately, AoE has the ugly aoe_discover() mechanism which means
that we still have a step() loop in aoe.c for now; this needs to be
replaced at some future point.
The PXE debugging messages have remained pretty much unaltered since
Etherboot 5.4, and are now difficult to read in comparison to most of
the rest of gPXE.
Bring the pxe_undi debug messages up to normal gPXE standards.
Expand the NETDEV_LINK_UP bit into a link_rc status code field,
allowing specific reasons for link failure to be reported via
"ifstat".
Originally-authored-by: Joshua Oreman <oremanj@rwcr.net>
In order to construct outgoing link-layer frames or parse incoming
ones properly, some protocols (such as 802.11) need more state than is
available in the existing variables passed to the link-layer protocol
handlers. To remedy this, add struct net_device *netdev as the first
argument to each of these functions, so that more information can be
fetched from the link layer-private part of the network device.
Updated all three call sites (netdevice.c, efi_snp.c, pxe_undi.c) and
both implementations (ethernet.c, ipoib.c) of ll_protocol to use the
new argument.
Signed-off-by: Michael Brown <mcb30@etherboot.org>
The 93C66 is identical to the 93C56 in programming interface and
addressing, but twice as large in data storage (4096 bits). It's
used in some RTL8185 wireless cards.
Signed-off-by: Michael Brown <mcb30@etherboot.org>
gPXE responds to duplicated ACKs with an immediate retransmission,
which can lead to a sorceror's apprentice syndrome. It also responds
to out-of-range (or old duplicate) ACKs with a RST, which can cause
valid connections to be dropped.
Fix the sorceror's apprentice syndrome by leaving the retransmission
timer running (and so inhibiting the immediate retransmission) when we
receive a potential duplicate ACK. This seems to match the behaviour
of Linux observed via wireshark traces.
Fix the RST issue by sending RST only on out-of-range ACKs that occur
before the connection is fully established, as per RFC 793.
These problems were exposed during development of the 802.11 wireless
link layer; the 802.11 protocol has a failure mode that can easily
cause duplicated packets. The fixes were tested in a controlled way
by faking large numbers of duplicated packets in the rtl8139 driver.
Originally-fixed-by: Joshua Oreman <oremanj@rwcr.net>
MAX_LL_HEADER_LEN is erroneously set to 6 rather than 14, resulting
in possible data corruption whenever we send an ARP packet.
Fix value and add a comment explaining why MAX_LL_ADDR_LEN is greater
than MAX_LL_HEADER_LEN.
Reported-by: Joshua Oreman <oremanj@rwcr.net>
Windows text editors such as Notepad tend to use CRLF line endings,
which breaks gPXE's signature detection for script images. Since
scripts are usually very small, they end up falling back to being
detected as valid PXE executable images (since there are no signature
checks for PXE executables). Executing text files as x86 machine code
tends not to work well.
Fix by allowing for any isspace() character to terminate the "#!gpxe"
signature, and by ensuring that CR characters get stripped during
command line parsing.
Suggested-by: Shao Miller <Shao.Miller@yrdsb.edu.on.ca>
Several SPI chips will respond to an SPI read command with a dummy
zero bit immediately prior to the first real data bit. This can be
used to autodetect the address length, provided that the command
length and data length are already known, and that the MISO data line
is tied high.
Tested-by: Thomas Miletich <thomas.miletich@gmail.com>
Debugged-by: Thomas Miletich <thomas.miletich@gmail.com>
For partly historical reasons, various files in the gPXE source tree
are licensed under different, though compatible, terms. Most of the
code is licensed under GPLv2 with the "or later" clause, but there are
exceptions such as:
The string.h file, which derives from Linux and is licensed as
Public Domain.
The EFI header files, which are taken from the EDK2 source tree and
are licensed under BSD.
The 3c90x driver, which has a custom GPL-like licence text.
Introduce a FILE_LICENCE() macro to make licensing more explicit.
This macro should be applied exactly once to each source (.c, .S or
.h) file. It will cause a corresponding zero-sized common symbol to
be added to any .o files generated from that source file (and hence to
any final gPXE binaries generated from that source file). Determining
the applicable licences to generated files can then be done using e.g.
$ objdump -t bin/process.o | grep __licence
00000000 O *COM* 00000001 .hidden __licence_gpl2_or_later
indicating that bin/process.o is covered entirely by the GPLv2
with the "or later" clause, or
$ objdump -t bin/rtl8139.dsk.tmp | grep __licence
00033e8c g O .bss.textdata 00000000 .hidden __licence_gpl2_only
00033e8c g O .bss.textdata 00000000 .hidden __licence_gpl2_or_later
00033e8c g O .bss.textdata 00000000 .hidden __licence_public_domain
indicating that bin/rtl8139.dsk includes both code licensed under
GPLv2 (both with and without the "or later" clause) and code licensed
as Public Domain.
Determining the result of licence combinations is currently left as an
exercise for the reader.
The Mac compiler treats "#pragma pack()" as gcc's "#pragma pack(pop)",
and so dies if the pragma pack stack is empty. Adding a "#pragma
pack(1)" immediately beforehand is enough to keep the Mac compiler
happy.
The combination of "#pragma pack(1)", "#pragma pack()" won't actually
achieve anything on a Mac, but it will at least build. (With gcc, the
"#pragma pack()" overrides any previous pragmas, so is still useful.)
Suggested-by: Joshua Oreman <oremanj@rwcr.net>
Eliminate the potential for mismatches between table names and the
table entry data type by incorporating the data type into the
definition of the table, rather than specifying it explicitly in each
table accessor method.
Intel's C compiler (icc) chokes on the zero-length arrays that we
currently use as part of the mechanism for accessing linker table
entries. Abstract away the zero-length arrays, to make a port to icc
easier.
Introduce macros such as for_each_table_entry() to simplify the common
case of iterating over all entries in a linker table.
Represent table names as #defined string constants rather than
unquoted literals; this avoids visual confusion between table names
and C variable or type names, and also allows us to force a
compilation error in the event of incorrect table names.
Allow for settings blocks to be created on demand. This allows for
constructions such as
set defaults/filename http://bootserver/bootfile
set defaults/priority 0xff
dhcp net0
chain ${filename}
which will boot from the DHCP-provided filename, or from
"http://bootserver/bootfile" if the DHCP server does not provide a
filename.
(Note that "priority" gets interpreted as a signed integer, so setting
"defaults/priority" to 0xff will cause the "defaults" settings block
to have an effective priority of -1.)
Having a default script containing
#!gpxe
autoboot
can cause problems when entering commands to load and start a kernel
manually; the default script image will still be present when the
kernel is started and so will be treated as an initrd. It is possible
to work around this by typing "imgfree" before any other commands, but
this is counter-intuitive.
Fix by allowing the embedded image list to be empty (in which case we
just call autoboot()), and making this the default.
Reported by alkisg@gmail.com.
Avoid passing credentials in the iBFT that were available but not
required for login. This works around a problem in the Microsoft
iSCSI initiator, which will refuse to initiate sessions if the CHAP
password is fewer than 12 characters, even if the target ends up not
asking for CHAP authentication.
It is a programming error, not a runtime error, if we attempt to use
block ciphers with an incorrect blocksize, so use an assert() rather
than an error status return.
The various types of cryptographic algorithm are fundamentally
different, and it was probably a mistake to try to handle them via a
single common type.
pubkey_algorithm is a placeholder type for now.
Certain combinations of PXE stack and BIOS result in a broken INT 18
call, which will leave the system displaying a "PRESS ANY KEY TO
REBOOT" message instead of proceeding to the next boot device. On
these systems, returning via the PXE stack is the only way to continue
to the next boot device. Returning via the PXE stack works only if we
haven't already blown away the PXE base code in pxeprefix.S.
In most circumstances, we do want to blow away the PXE base code.
Base memory is a limited resource, and it is desirable to reclaim as
much as possible. When we perform an iSCSI boot, we need to place the
iBFT above the 512kB mark, because otherwise it may not be detected by
the loaded OS; this may not be possible if the PXE base code is still
occupying that memory.
Introduce a new prefix type .kkpxe which will preserve both the PXE
base code and the UNDI driver (as compared to .kpxe, which preserves
the UNDI driver but uninstalls the PXE base code). This prefix type
can be used on systems that are known to experience the specific
problem of INT 18 being broken, or in builds (such as gpxelinux.0) for
which it is particularly important to know that returning to the BIOS
will work.
Written by H. Peter Anvin <hpa@zytor.com> and Stefan Hajnoczi
<stefanha@gmail.com>, minor structural alterations by Michael Brown
<mcb30@etherboot.org>.
Multi-level menus via COMBOOT rely on the COMBOOT program being able
to exit and invoke a new COMBOOT program (the next menu). This works,
but rapidly (within about five iterations) runs out of space in gPXE's
internal stack, since each new image is executed in a new function
context.
Fix by allowing tail recursion between images; an image can now
specify a replacement image for itself, and image_exec() will perform
the necessary tail recursion.
This patch extends the embedded image feature to allow multiple
embedded images instead of just one.
gPXE now always boots the first embedded image on startup instead of
doing the hardcoded DHCP boot (aka autoboot).
Based heavily upon a patch by Stefan Hajnoczi <stefanha@gmail.com>.
Various combinations of options 43.6, 43.7 and 43.8 dictate which
servers we send Boot Server Discovery requests to, and which servers
we should accept responses from. Obey these options, and remove the
explicit specification of a single Boot Server from start_pxebs() and
dependent functions.
There are many functions that take ownership of the I/O buffer they
are passed as a parameter. The caller should not retain a pointer to
the I/O buffer. Use iob_disown() to automatically nullify the
caller's pointer, e.g.:
xfer_deliver_iob ( xfer, iob_disown ( iobuf ) );
This will ensure that iobuf is set to NULL for any code after the call
to xfer_deliver_iob().
iob_disown() is currently used only in places where it simplifies the
code, by avoiding an extra line explicitly setting the I/O buffer
pointer to NULL. It should ideally be used with each call to any
function that takes ownership of an I/O buffer. (The SSA
optimisations will ensure that use of iob_disown() gets optimised away
in cases where the caller makes no further use of the I/O buffer
pointer anyway.)
If gcc ever introduces an __attribute__((free)), indicating that use
of a function argument after a function call should generate a
warning, then we should use this to identify all applicable function
call sites, and add iob_disown() as necessary.
The DHCP client code now implements only the mechanism of the DHCP and
PXE Boot Server protocols. Boot Server Discovery can be initiated
manually using the "pxebs" command. The menuing code is separated out
into a user-level function on a par with boot_root_path(), and is
entered in preference to a normal filename boot if the DHCP vendor
class is "PXEClient" and the PXE boot menu option exists.
Try to qualify relative names in the DNS resolver using the DHCP Domain
Name. For example:
DHCP Domain Name: etherboot.org
(Relative) Name: www
yields:
www.etherboot.org
Only names with no dots ('.') will be modified. A name with one or more
dots is unchanged.
PXE dictates a mechanism for boot menuing, involving prompting the
user with a variable message, waiting for a predefined keypress,
displaying a boot menu, and waiting for a selection.
This breaks the currently desirable abstraction that DHCP is a process
that can happen in the background without any user interaction.
F8 is represented by the ANSI escape sequence "^[[19~", which is not
representable as a KEY_xxx constant using the current encoding scheme.
Adapt the encoding scheme to allow F8 to be represented, since PXE
requires that we may need to prompt the user to press F8.
Remove the lazy assumption that ProxyDHCP == "DHCP with option 60 set
to PXEClient", and explicitly separate the notion of ProxyDHCP from
the notion of packets containing PXE options.
Pick out the first boot menu item from the boot menu (option 43.9) and
pass it to the boot server as the boot menu item (option 43.71).
Also improve DHCP debug messages to include more details of the
packets being transmitted.
Some PXE configurations require us to perform a third DHCP transaction
(in addition to the real DHCP transaction and the ProxyDHCP
transaction) in order to retrieve information from a "Boot Server".
This is an experimental implementation, since the actual behaviour is
not well specified in the PXE spec.
When sending to a multicast address, it may be necessary to specify
the source address explicitly, since the multicast destination address
does not provide enough information to deduce the source address via
the miniroute table.
Allow the source address specified via the data-xfer metadata to be
passed down through the TCP/IP stack to the IPv4 layer, which can use
it as a default source address.
Include a minimal component name protocol so that the driver name
shows up as something other than "<UNKNOWN>" in the driver list, and a
device path protocol so that the network interface shows up as a
separate device in the device list, rather than being attached
directly to the PCI device.
Incidentally, the EFI component name protocol reaches new depths for
signal-to-noise ratio in program code. A typical instance within the
EFI development kit will use an additional 300 lines of code to
provide slightly less functionality than GNU gettext achieves with
three additional characters.
elf2efi converts a suitable ELF executable (containing relocation
information, and with appropriate virtual addresses) into an EFI
executable. It is less tightly coupled with the gPXE build process
and, in particular, does not require the use of a hand-crafted PE
image header in efiprefix.S.
elf2efi correctly handles .bss sections, which significantly reduces
the size of the gPXE EFI executable.
Conventional usage of the various struct sockaddr_xxx types involves
liberal use of casting, which tends to trigger strict-aliasing
warnings from gcc. Avoid these now and in future by marking all the
relevant types with __attribute__((may_alias)).
Currently the only supported platform for x86_64 is EFI.
Building an EFI64 gPXE requires a version of gcc that supports
__attribute__((ms_abi)). This currently means a development build of
gcc; the feature should be present when gcc 4.4 is released.
In the meantime; you can grab a suitable gcc tree from
git://git.etherboot.org/scm/people/mcb30/gcc/.git
EFI provides a copy of the SMBIOS table accessible via the EFI system
table, which we should use instead of manually scanning through the
F000:0000 segment.
EFI passes in copies of SMBIOS and other system configuration tables
via the EFI system table. Allow configuration tables to be requested
using a mechanism similar to the current method for requesting EFI
protocols.
This driver is based on Stefan Hajnoczi's summer work, which
is in turn based on version 1.01 of the linux b44 driver.
I just assembled the pieces and fixed/added a few pieces
here and there to make it work for my hardware.
The most major limitation is that this driver won't work
on systems with >1GB RAM due to the card not having enough
address bits for that and gPXE not working around this
limitation.
Still, other than that the driver works well enough for
at least 2 users :) and the above limitation can always
be fixed when somebody wants it bad enough :)
Signed-off-by: Pantelis Koukousoulas <pktoss@gmail.com>
There are currently four places within the codebase that use a
heuristic to guess the "boot network device", with varying degrees of
success. Add a feature to the net device core to maintain a list of
open network devices, in order of opening, and provide a function
last_opened_netdev() to retrieve the most recently opened net device.
This should do a better job than the current assortment of
guess_boot_netdev() functions.
The AoE spec does not specify that the source MAC address of a
received packet actually matches the MAC address of the AoE target.
In principle an AoE server can respond to an AoE request on any
interface available to it, which may not be an address configured to
accept AoE requests.
This issue is resolved by implementing AoE device discovery. The
purpose of AoE discovery is to find out which addresses an AoE target
can use for requests. An AoE configuration command is sent when the
AoE attach is attempted. The AoE target must respond to that
configuration query from an interface that can accept requests.
Based on a patch from Ryan Thomas <ryan@coraid.com>
EFI_STATUS is defined as an INTN, which maps to UINT32 (i.e. unsigned
int) on i386 and UINT64 (i.e. unsigned long) on x86_64. This would
require a cast each time the error status is printed.
Add efi_strerror() to avoid this ickiness and simultaneously enable
prettier reporting of EFI status codes.
The return path in directed route SMPs lists the egress ports in order
from SM to node, rather than from node to SM.
To write to the correct offset within the return path, we need to
parse the hop pointer. This is held within the class-specific data
portion of the MAD header, which was previously unused by us and
defined to be a uint16_t. Define this field to be a union type; this
requires some rearrangement of ib_mad.h and corresponding changes to
ipoib.c.
These cards very nearly support our current IB Verbs model. There is
one minor difference: multicast packets will always be delivered by
the hardware to QP0, so the driver has to redirect them to the
appropriate QP. This means that QP owners may see receive completions
for buffers that they never posted. Nothing in our current codebase
will break because of this.
This can be used with cards that require the driver to construct and
parse packet headers manually. Headers are optionally handled
out-of-line from the packet payload, since some such cards will split
received headers into a separate ring buffer.
Some Infiniband cards will not be as accommodating as the Arbel and
Hermon cards in providing enough space for us to push a fake extra
header at the start of the received packet. We must therefore make do
with squeezing enough information to identify source and destination
addresses into the two bytes of padding within a genuine IPoIB
link-layer header.
Not all Infiniband cards have embedded subnet management agents.
Split out the code that communicates with such an embedded SMA into a
separate ib_smc.c file, and have drivers call ib_smc_update()
explicitly when they suspect that the answers given by the embedded
SMA may have changed.
Receive completion handlers now get passed an address vector
containing the information extracted from the packet headers
(including the GRH, if present), and only the payload remains in the
I/O buffer.
This breaks the symmetry between transmit and receive completions, so
remove the ib_completer_t type and use an ib_completion_queue_operations
structure instead.
Rename the "destination QPN" and "destination LID" fields in struct
ib_address_vector to reflect its new dual usage.
Since the ib_completion structure now contains only an IB status code,
("syndrome") replace it with a generic gPXE integer status code.
Avoid leaking I/O buffers in ib_destroy_qp() by completing any
outstanding work queue entries with a generic error code. This
requires the completion handlers to be available to ib_destroy_qp(),
which is done by making them static configuration parameters of the CQ
(set by ib_create_cq()) rather than being provided on each call to
ib_poll_cq().
This mimics the functionality of netdev_{tx,rx}_flush(). The netdev
flush functions would previously have been catching any I/O buffers
leaked by the IPoIB data queue (though not by the IPoIB metadata
queue).
Add the simplified ne2k_isa driver. It is just a selective copy+paste
of the relevant parts from ns8390.c plus a little trivial hacking to
make it actually work.
It is true that the code is pretty ugly, but:
a) ns8390.c is worse
b) It is only 372 lines and no #ifdefs
c) It works both in qemu/bochs and in real hardware
and we all know it is easier to cleanup working code
Hope someone will find the time to rewrite this driver properly,
but until then at least for me this is an ok solution.
Signed-off-by: Pantelis Koukousoulas <pktoss@gmail.com>
netdev_rx_err() and netdev_tx_complete_err() get passed the error
code, but currently use it only in debug messages.
Retain error numbers and frequencey counts for up to
NETDEV_MAX_UNIQUE_ERRORS (4) different errors for each of TX and RX.
This allows the "ifstat" command to report the reasons for TX/RX
errors in most cases, even in non-debug builds.
Settings can be constructed using a dotted-decimal notation, to allow
for access to unnamed settings. The default interpretation is as a
DHCP option number (with encapsulated options represented as
"<encapsulating option>.<encapsulated option>".
In several contexts (e.g. SMBIOS, Phantom CLP), it is useful to
interpret the dotted-decimal notation as referring to non-DHCP
options. In this case, it becomes necessary for these contexts to
ignore standard DHCP options, otherwise we end up trying to, for
example, retrieve the boot filename from SMBIOS.
Allow settings blocks to specify a "tag magic". When dotted-decimal
notation is used to construct a setting, the tag magic value of the
originating settings block will be ORed in to the tag number.
Store/fetch methods can then check for the magic number before
interpreting arbitrarily-numbered settings.
EFI requires us to be able to specify the source address for
individual transmitted packets, and to be able to extract the
destination address on received packets.
Take advantage of this to rationalise the push() and pull() methods so
that push() takes a (dest,source,proto) tuple and pull() returns a
(dest,source,proto) tuple.
Multicast hashing is an ugly overlap between network and link layers.
EFI requires us to provide access to this functionality, so move it
out of ipv4.c and expose it as a method of the link layer.
We have EFI APIs for CPU I/O, PCI I/O, timers, console I/O, user
access and user memory allocation.
EFI executables are created using the vanilla GNU toolchain, with the
EXE header handcrafted in assembly and relocations generated by a
custom efilink utility.
The userptr_t is now the fundamental type that gets used for conversions.
For example, virt_to_phys() is implemented in terms of virt_to_user() and
user_to_phys().
-Wformat-nonliteral is not enabled by -Wall and needs to be explicitly
specified.
Modified the few files that use nonliteral format strings to work with
this new setting in place.
Inspired by a patch from Carl Karsten <carl@personnelware.com> and an
identical patch from Rorschach <r0rschach@lavabit.com>.
The intention is to include near-verbatim copies of the EFI headers
required by gPXE. This is achieved using the import.pl script in
src/include/gpxe/efi.
Note that import.pl will modify any #include lines in each imported
header to reflect its new location within the gPXE tree. It will also
tidy up the file by removing carriage return characters and trailing
whitespace.
Some devices (e.g. the Atmel AT24C11) have no concept of a device
address; they respond to every device address and use this value as
the word address. Some other devices use part of the device address
field to extend the word address field.
Generalise the i2c bit-bashing support to handle this by defining the
device address length and word address length as properties of an i2c
device. The word address is assumed to overflow into the device
address field if the address used exceeds the width of the word
address field.
Also add a bus reset mechanism. i2c chips don't usually have a reset
line, so rebooting the host will not clear any bizarre state that the
chip may be in. We reset the bus by clocking SCL until we see SDA
high, at which point we know we can generate a start condition and
have it seen by all devices. We then generate a stop condition to
leave the bus in a known state prior to use.
Finally, add some extra debugging messages to i2c_bit.c.
The usefulness of DBGLVL_IO is limited by the fact that many cards
require large numbers of uninteresting I/O reads/writes at device
probe time, typically when driving a bit-bashing I2C/SPI bus to read
the MAC address.
This patch adds the DBG_DISABLE() and DBG_ENABLE() macros, which can
be used to temporarily disable and re-enable selected debug levels.
Note that debug levels must still be enabled in the build in order to
function at all: you can't use DBG_ENABLE(DBGLVL_IO) in an object
built with DEBUG=object:1 and expect it to do anything.
Determine the network-layer packet type and fill it in for UNDI
clients. This is required by some NBPs such as emBoot's winBoot/i.
This change requires refactoring the link-layer portions of the
gPXE netdevice API, so that it becomes possible to strip the
link-layer header without passing the packet up the network stack.
Allow for an arbitrary number of splits of the system memory map via
INT 15,e820.
Features of the new map-mangling algorithm include:
Supports random access to e820 map entries.
Requires only sequential access support from the underlying e820
map, even if our caller uses random access.
Empty regions will always be stripped.
Always terminates with %ebx=0, even if the underlying map terminates
with CF=1.
Allows for an arbitrary number of hidden regions, with underlying
regions split into as many subregions as necessary.
Total size increase to achieve this is 193 bytes.
New min_timeout and max_timeout fields in struct retry_timer allow
users of this timer to set their own desired minimum and maximum
timeouts, without being constrained to a single global minimum and
maximum. Users of the timer can still elect to use the default global
values by leaving the min_timeout and max_timeout fields as 0.
When we boot from a DHCP-supplied filename, we previously relied on
the fact that the current working URI is set to tftp://[next-server]/
in order to resolve the filename into a full tftp:// URI. However,
this process will eliminate the distinction between filenames with and
without initial slashes:
cwuri="tftp://10.0.0.1/" filename="vmlinuz" => URI="tftp://10.0.0.1/vmlinuz"
cwuri="tftp://10.0.0.1/" filename="/vmlinuz" => URI="tftp://10.0.0.1/vmlinuz"
This distinction is important for some TFTP servers. We now
explicitly construct a string of the form
"tftp://[next-server]/filename"
so that a filename with an initial slash will result in a URI
containing a double-slash, e.g.
"tftp://10.0.0.1//vmlinuz"
The TFTP code always strips a single initial slash, and so ends up
presenting the correct path to the server.
URIs entered explicitly by users at the command line must include a
double slash if they want an initial slash presented to the TFTP
server:
"kernel tftp://10.0.0.1/vmlinuz" => filename="vmlinuz"
"kernel tftp://10.0.0.1//vmlinuz" => filename="/vmlinuz"
In tg3_chip_reset(), the PCI_EXPRESS change is taken from the Linux
tg3 driver. I am not sure what exactly it does (it is not documented
in the Linux driver), but it is necessary for the NIC to work
correctly.
Add yet another ugly hack to iscsiboot.c, this time to allow the user to
inhibit the shutdown/removal of the iSCSI INT13 device (and the network
devices, since they are required for the iSCSI device to function).
On the plus side, the fact that shutdown() now takes flags to
differentiate between shutdown-for-exit and shutdown-for-boot means that
another ugly hack (to allow returning via the PXE stack on BIOSes that
have broken INT 18 calls) will be easier.
I feel dirty.
We can just treat all non-kernel images as initrds, which matches our
behaviour for multiboot kernels. This allows us to eliminate initrd as
an image type, and treat the "initrd" command as just another synonym for
"imgfetch".
This commit implements GDB over UDP. Using UDP is more complex than
serial and has required some restructuring.
The GDB stub is now built using one or both of GDBSERIAL and GDBUDP
config.h options.
To enter the debugger, execute the gPXE shell command:
gdbstub <transport> [<options>...]
Where <transport> is "serial" or "udp". For "udp", the name of a
configured network device is required:
gdbstub udp net0
The GDB stub listens on UDP port 43770 by default.
Some drivers that still use the legacy-driver wrapper (tg3 in particular)
apparently do not specify their alignment constraints properly. This
hack forces any __shared data to be maximally aligned.
Note that this provides only 16-byte alignment; it is not possible to
request alignment to any greater than 16 bytes using
__attribute__((aligned)), since the relocation code will preserve only 16
byte alignment (and operation under -DKEEP_IT_REAL cannot preserve more
that 16 byte alignment).
Idea proposed by Tim Hockin <thockin@google.com>
UDP sockets can be used for multicast, at which point it becomes
plausible that we could receive packets that aren't destined for us
but that still match on a port number.
Delete ELF as a generic image type. The method for invoking an
ELF-based image (as well as any tables that must be set up to allow it
to boot) will always depend on the specific architecture. core/elf.c
now only provides the elf_load() function, to avoid duplicating
functionality between ELF-based image types.
Add arch/i386/image/elfboot.c, to handle the generic case of 32-bit
x86 ELF images. We don't currently set up any multiboot tables, ELF
notes, etc. This seems to be sufficient for loading kernels generated
using both wraplinux and coreboot's mkelfImage.
Note that while Etherboot 5.4 allowed ELF images to return, we don't.
There is no callback mechanism for the loaded image to shut down gPXE,
which means that we have to shut down before invoking the image. This
means that we lose device state, protection against being trampled on,
etc. It is not safe to continue afterwards.
Michael Brown