[tcp] Do not shrink window when discarding received packets
We currently shrink the TCP window permanently if we are ever forced
(by a low-memory condition) to discard a previously received TCP
packet. This behaviour was intended to reduce the number of
retransmissions in a lossy network, since lost packets might
potentially result in the entire window contents being retransmitted.
Since commit e0fc8fe ("[tcp] Implement support for TCP Selective
Acknowledgements (SACK)") the cost of lost packets has been reduced by
around one order of magnitude, and the reduction in the window size
(which affects the maximum throughput) is now the more significant
cost.
Remove the code which reduces the TCP maximum window size when a
received packet is discarded.
Reported-by: Wissam Shoukair <wissams@mellanox.com>
Tested-by: Wissam Shoukair <wissams@mellanox.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some HP BIOSes (observed with an HP ProLiant m710p Server Cartridge)
have a bug in the implementation of INT 1a,b101: they blithely assume
that real-mode code is able to read from anywhere in the 32-bit memory
space.
This problem affects the call to INT 1a,b101 made from within
pcibios_num_bus() (which uses REAL_CODE() and hence executes in
genuine real mode) but does not affect the call made from within
romprefix.S (since with a PMM BIOS, that call executes in flat real
mode anyway).
Work around the problem by explicitly calling flatten_real_mode()
before invoking INT 1a,b101. This is a rarely-used code path, and so
the extra overhead of emulating instructions in some VM configurations
(see commit 6d4deee ("[librm] Use genuine real mode to accelerate
operation in virtual machines") for more details) is negligible.
Reported-by: Wissam Shoukair <wissams@mellanox.com>
Debugged-by: Wissam Shoukair <wissams@mellanox.com>
Debugged-by: Michael Brown <mcb30@ipxe.org>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[xhci] Ignore invalid protocol speed ID values on Intel Skylake platforms
Some Intel Skylake platforms (observed on a prototype Lenovo ThinkPad)
report the list of available USB3 protocol speed ID values as {1,2,3}
but then report a port's speed using ID value 4.
The value 4 happens to be the default value for SuperSpeed (when no
protocol speed ID value list is explicitly defined), and the hardware
seems to function correctly if we simply ignore its protocol speed ID
table and assume that it uses the default values.
Fix by adding a "broken PSI values" quirk for this controller.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[xhci] Fix comparison of signed and unsigned integers
gcc 4.8.2 fails to report this erroneous comparison unless assertions
are enabled.
Reported-by: Mary-Ann Johnson <MaryAnn.Johnson@displaylink.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[build] Fix .ids.o creation for drivers not in the all-drivers build
Commit dc19e63 ("[build] Construct all-drivers list based on driver
class") accidentally excluded the USB bus drivers from the list of
files parsed in order to create PCI 3.0 device ID lists.
Fix by returning $(DRIVERS) to its previous definition as a list of
all driver files, and use only $(DRIVERS_ipxe) to contain the
filtered list containing only those drivers which we want to include
in the "all-drivers" build.
Reported-by: Mary-Ann Johnson <MaryAnn.Johnson@displaylink.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The xHCI slot ID is one-based, not zero-based. Fix the length of the
xhci->slot[] array to account for this, and add assertions to check
that the hardware returns a valid slot ID in response to the Enable
Slot command.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[neighbour] Return success when deferring a packet
Deferral of a packet for neighbour discovery is not really an error.
If we fail to discover a neighbour then the failure will eventually be
reported by the call to neighbour_destroy() when any outstanding I/O
buffers are discarded.
The current behaviour breaks PXE booting on FreeBSD, which seems to
treat the error return from PXENV_UDP_WRITE as a fatal error and so
never proceeds to poll PXENV_UDP_READ (and hence never allows iPXE to
receive the ARP reply and send the deferred UDP packet).
Change neighbour_tx() to return success when deferring a packet. This
fixes interoperability with FreeBSD and removes transient neighbour
cache misses from the "ifstat" error output, while leaving genuine
neighbour discovery failures visible via "ifstat" (once neighbour
discovery times out, or the interface is closed).
Debugged-by: Wissam Shoukair <wissams@mellanox.com>
Tested-by: Wissam Shoukair <wissams@mellanox.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[intel] Fix operation when physical function has jumbo frames enabled
When jumbo frames are enabled, the Linux ixgbe physical function
driver will disable the virtual function's receive datapath by
default, and will enable it only if the virtual function negotiates
API version 1.1 (or higher) and explicitly selects an MTU.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[int13con] Add basic ability to log to a local disk via INT 13
Several popular public cloud providers do not provide any sensible
mechanism for obtaining debug output from an OS which is failing to
boot. For example, Amazon EC2 provides the "Get System Log" facility,
which occasionally deigns to report a random subset of the characters
emitted via the VM's serial port, but usually returns only a blank
screen. (Amazingly, this is still superior to the debugging
facilities provided by Azure.)
Work around these shortcomings by adding a console type which sends
output to a magically detected raw disk partition, and including such
a partition within any iPXE .usb-format image.
To use this facility:
- build an iPXE .usb image with CONSOLE_INT13 enabled
- boot the cloud VM from this image
- after the boot fails, attach the VM's boot disk to a second VM
- from this second VM, use "less -f -R /dev/sdb3" (or similar) to
view the iPXE output.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[intel] Add support for mailbox used by virtual functions
Virtual functions use a mailbox to communicate with the physical
function driver: this covers functionality such as obtaining the MAC
address.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[intel] Allow for the use of advanced TX descriptors
Intel virtual function NICs almost work with the use of "legacy"
transmit and receive descriptors (which are backwards compatible right
back to the original Intel Gigabit NICs).
Unfortunately the "TX switching" feature (which allows for VM<->VM
traffic to be looped back within the NIC itself) does not work when a
legacy TX descriptor is used: the packet is instead sent onto the
wire.
Fix by allowing for the use of an "advanced" TX descriptor (containing
exactly the same information as is found in the "legacy" descriptor).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[usb] Always clear recorded disconnections after performing hotplug actions
The recorded disconnections (in port->disconnected) will currently be
left uncleared if usb_attached() returns an error (e.g. because there
are no drivers for a particular USB device). This is incorrect
behaviour: the disconnection has been handled and the record should be
cleared until the next physical disconnection is detected (via the CSC
bit).
The problem is masked for EHCI, UHCI, and USB hubs, since these will
report a changed port (via usb_port_changed()) only when the
underlying hardware reports a change. xHCI will call
usb_port_changed() in response to any port status event, at which
point the stale value of port->disconnected will be erroneously acted
upon. This can lead to an endless loop of repeatedly enumerating the
same device when a driverless device is attached to an xHCI root hub
port.
Fix by unconditionally clearing port->disconnected in usb_hotplugged().
Reported-by: Robin Smidsrød <robin@smidsrod.no>
Tested-by: Robin Smidsrød <robin@smidsrod.no>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[usb] Do not call usb_hotplug() when registering a new hub
The action of registering a new hub can itself happen in only two
ways: either a new USB hub has been created (in which case we are
already inside a call to usb_hotplug()), or a new root hub has been
created.
In the former case, we do not need to issue a further call to
usb_hotplug(), since the hub's ports will all be marked as changed and
so will be handled after the return from register_usb_hub() anyway.
Calling usb_hotplug() within register_usb_hub() leads to a confusing
order of events, such as:
- root hub port 1 detects a change
- root hub port 2 detects a change
- usb_hotplug() is called
- root hub port 1 finds a USB hub
- usb_hotplug() is called
- this inner call to usb_hotplug() handles root hub port 2
Fix by calling usb_hotplug() only from usb_step() and from
register_usb_bus(). This avoids recursive calls to usb_hotplug() and
ensures that devices are enumerated in the order of detection.
Tested-by: Robin Smidsrød <robin@smidsrod.no>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
When USB network card drivers are used, the BIOS' legacy USB
capability is necessarily disabled since there is no way to share the
host controller between the BIOS and iPXE. This currently results in
USB keyboards becoming non-functional in USB-enabled builds of iPXE.
Fix by adding basic support for USB keyboards, enabled by default in
iPXE builds which include USB support.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[usb] Maintain single lists of halted endpoints and changed ports
When an EHCI hotplug action results in the controller disowning the
port, it will result in a hotplug action on the corresponding UHCI or
OHCI controller. Allow such hotplug actions to be carried out as part
of the same call to usb_step() or usb_register_bus(), by maintaining a
single central list of changed ports.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The USB core will currently fail to detect disconnections if a new
device has attached by the time the port is examined in
usb_hotplug().
Fix by recording the fact that a disconnection has taken place
whenever the "connection status changed" (CSC) bit is observed to be
set. (Whether the change represents a disconnection or a
reconnection, it indicates that the port has experienced some time of
being disconnected.)
Note that the time at which a disconnection can be detected varies by
hub type. In particular: root hubs can observe the CSC bit when
polling, and so will record the disconnection before calling
usb_port_changed(), but USB hubs read the port status (and hence the
CSC bit) only during the call to hub_speed(), long after the call to
usb_port_changed().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[pci] Provide PCI_CLASS() to calculate a scalar PCI class value
Rename PCI_CLASS() (which constructs a struct pci_class_id) to
PCI_CLASS_ID(), and provide PCI_CLASS() as a macro which constructs
the 24-bit scalar value of a PCI class code.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[usb] Include setup packet within I/O buffer for message transfers
The USB API currently assumes that host controllers will have
immediate data buffer space available in which to store the setup
packet. This is true for xHCI, partially true for EHCI (which happens
to have 12 bytes of padding in each transfer descriptor due to
alignment requirements), and not true at all for UHCI.
Include the setup packet within the I/O buffer passed to the host
controller's message() method, thereby eliminating the requirement for
host controllers to provide immediate data buffers.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[vram] Add "vram" built-in setting to dump video RAM
The "vram" setting returns the (Base64-encoded) contents of video RAM,
and can be used to capture a screenshot. For example: after running
memtest.0 and encountering an error, the output can be captured and
sent to a remote server for later diagnosis:
#!ipxe
chain -a http://server/memtest.0 && goto ok || goto bad
:bad
params
param errno ${errno}
param vram ${vram}
chain -a http://server/report.php##params
:ok
Inspired-by: Christian Nilsson <nikize@gmail.com>
Originally-implemented-by: Christian Nilsson <nikize@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[base16] Add buffer size parameter to base16_encode() and base16_decode()
The current API for Base16 (and Base64) encoding requires the caller
to always provide sufficient buffer space. This prevents the use of
the generic encoding/decoding functionality in some situations, such
as in formatting the hex setting types.
Implement a generic hex_encode() (based on the existing
format_hex_setting()), implement base16_encode() and base16_decode()
in terms of the more generic hex_encode() and hex_decode(), and update
all callers to provide the additional buffer length parameter.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[test] Include IPv6 support when performing settings self-tests
The settings self-tests include tests for the "ipv6" setting type.
When IPv6 support is not included, this setting type exists (since it
is referred to by some dual-stack code, such as dns.c) but is
non-functional.
Force IPv6 support to be included within a settings self-test build
using an explicit REQUIRE_OBJECT() macro.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[ath9k] Remove confusing logic inversion in an ANI variable
This changed in Linux kernel the same way in commit 7067e701
("ath9k_hw: remove confusing logic inversion in an ANI variable") by
Felix Fietkau.
Additionally this fixes "error: logical not is only applied to the
left hand side of comparison" with GCC 5.1.0.
Signed-off-by: Christian Hesse <mail@eworm.de>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
This fixes "initialization discards 'const' qualifier from pointer
target type" warnings with GCC 5.1.0.
Signed-off-by: Christian Hesse <mail@eworm.de>
Modified-by: Michael Brown <mcb30@ipxe.org>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[intel] Add PCI device IDs for Intel I218-LM and I218-V
I218-LM (rev 3) is found in Lenovo Thinkpad X250. The remaining
device IDs are from linux/drivers/net/ethernet/intel/e1000e/hw.h
Signed-off-by: Christian Hesse <mail@eworm.de>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[build] Construct all-drivers list based on driver class
The USB bus drivers (ehci.c and xhci.c) have PCI device ID tables and
hence PCI_ROM() lines, but should probably not be included in the
all-drivers build on this basis, since they do nothing useful unless a
USB network driver is also present.
Fix by constructing the all-drivers list based on the driver class
(i.e. the portion of the source path immediately after "drivers/").
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[realtek] Do not attempt to access EEPROM on RTL8169 chips
On some RTL8169 onboard NICs (observed with a Lenovo ThinkPad 11e),
the EEPROM is not merely not present: any attempt to read from the
non-existent EEPROM will crash and reboot the system.
The equivalent code to read from the EEPROM was removed from the Linux
r8169 driver in 2009 with a comment suggesting that it was similarly
found to be unreliable on some systems.
Fix by accessing the EEPROM only on RTL8139 NICs, and assuming that
the MAC address will always be correctly preset on RTL8169 NICs.
Reported-by: Evan Prohaska <eprohaska@edkey.org>
Tested-by: Evan Prohaska <eprohaska@edkey.org>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[intel] Force RX polling on VMware emulated 82545em
The emulated Intel 82545em in some versions of VMware (observed with
ESXi v5.1) seems to sometimes fail to set the RXT0 bit in the
interrupt cause register (ICR), causing iPXE to stop receiving
packets. Work around this problem (for the 82545em only) by always
polling the receive queue regardless of the state of the ICR.
Reported-by: Slava Bendersky <volga629@networklab.ca>
Tested-by: Slava Bendersky <volga629@networklab.ca>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown