summaryrefslogtreecommitdiffstats
path: root/src/interface/efi/efi_init.c
Commit message (Collapse)AuthorAgeFilesLines
* [efi] Accept a command line passed to an iPXE image via LoadOptionsMichael Brown2023-01-291-0/+5
| | | | | | | | | Treat a command line passed to iPXE via UEFI LoadOptions as an image to be registered at startup, as is already done for the .lkrn, .pxe, and .exe BIOS images. Originally-implemented-by: Ladi Prosek <lprosek@redhat.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Run ExitBootServices shutdown hook at TPL_NOTIFYMichael Brown2021-11-231-3/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On some systems (observed with the Thunderbolt ports on a ThinkPad X1 Extreme Gen3 and a ThinkPad P53), if the IOMMU is enabled then the system firmware will install an ExitBootServices notification event that disables bus mastering on the Thunderbolt xHCI controller and all PCI bridges, and destroys any extant IOMMU mappings. This leaves the xHCI controller unable to perform any DMA operations. As described in commit 236299b ("[xhci] Avoid DMA during shutdown if firmware has disabled bus mastering"), any subsequent DMA operation attempted by the xHCI controller will end up completing after the operating system kernel has reenabled bus mastering, resulting in a DMA operation to an area of memory that the hardware is no longer permitted to access and, on Windows with the Driver Verifier enabled, a STOP 0xE6 (DRIVER_VERIFIER_DMA_VIOLATION). That commit avoids triggering any DMA attempts during the shutdown of the xHCI controller itself. However, this is not a complete solution since any attached and opened USB device (e.g. a USB NIC) may asynchronously trigger DMA attempts that happen to occur after bus mastering has been disabled but before we reset the xHCI controller. Avoid this problem by installing our own ExitBootServices notification event at TPL_NOTIFY, thereby causing it to be invoked before the firmware's own ExitBootServices notification event that disables bus mastering. This unsurprisingly causes the shutdown hook itself to be invoked at TPL_NOTIFY, which causes a fatal error when later code attempts to raise the TPL to TPL_CALLBACK (which is a lower TPL). Work around this problem by redefining the "internal" iPXE TPL to be variable, and set this internal TPL to TPL_NOTIFY when the shutdown hook is invoked. Avoid calling into an underlying SNP protocol instance from within our shutdown hook at TPL_NOTIFY, since the underlying SNP driver may attempt to raise the TPL to TPL_CALLBACK (which would cause a fatal error). Failing to shut down the underlying SNP device is safe to do since the underlying device must, in any case, have installed its own ExitBootServices hook if any shutdown actions are required. Reported-by: Andreas Hammarskjöld <junior@2PintSoftware.com> Tested-by: Andreas Hammarskjöld <junior@2PintSoftware.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Raise TPL during driver unload entry pointMichael Brown2021-11-221-0/+7
| | | | | | | | | | | | The efi_unload() function is currently missing the calls to raise and restore the TPL. This has the side effect of causing iPXE to return from the driver unload entry point at TPL_CALLBACK, which will cause unexpected behaviour (typically a system lockup) shortly afterwards. Fix by adding the missing calls to raise and restore the TPL. Debugged-by: Petr Borsodi <petr.borsodi@gmail.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Avoid dropping below TPL as at entry to iPXEMichael Brown2020-11-201-0/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | iPXE will currently drop to TPL_APPLICATION whenever the current system time is obtained via currticks(), since the system time mechanism relies on a timer that can fire only when the TPL is below TPL_CALLBACK. This can cause unexpected behaviour if the system time is obtained in the middle of an API call into iPXE by external code. For example, MnpDxe sets up a 10ms periodic timer running at TPL_CALLBACK to poll the underling EFI_SIMPLE_NETWORK_PROTOCOL device for received packets. If the resulting poll within iPXE happens to hit a code path that requires obtaining the current system time (e.g. due to reception of an STP packet, which affects iPXE's blocked link timer), then iPXE will end up temporarily dropping to TPL_APPLICATION. This can potentially result in retriggering the MnpDxe periodic timer, causing code to be unexpectedly re-entered. Fix by recording the external TPL at any entry point into iPXE and dropping only as far as this external TPL, rather than dropping unconditionally to TPL_APPLICATION. The side effect of this change is that iPXE's view of the current system time will be frozen for the duration of any API calls made into iPXE by external code at TPL_CALLBACK or above. Since any such external code is already responsible for allowing execution at TPL_APPLICATION to occur, then this should not cause a problem in practice. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Split device path functions out to efi_path.cMichael Brown2020-10-161-2/+2
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Use device path to locate filesystem from which we were loadedMichael Brown2020-08-031-0/+40
| | | | | | | | | | | | | | | | | | | The file:/ URI syntax may be used to refer to local files on the filesystem from which the iPXE binary was loaded. This is currently implemented by directly using the DeviceHandle recorded in our EFI_LOADED_IMAGE_PROTOCOL. This mechanism will fail when a USB-enabled build of iPXE is loaded from USB storage and subsequently installs its own USB host controller drivers, since doing so will disconnect and reconnect the existing USB storage drivers and thereby invalidate the original storage device handle. Fix by recording the device path for the loaded image's DeviceHandle at initialisation time and later using the recorded device path to locate the appropriate device handle. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Ensure NUL byte is at lowest address within stack cookieMichael Brown2020-07-091-0/+8
| | | | | | | | | | The NUL byte included within the stack cookie to act as a string terminator should be placed at the lowest byte address within the stack cookie, in order to avoid potentially including the stack cookie value within an accidentally unterminated string. Suggested-by: Pete Beck <pete.beck@ioactive.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Distribute available entropy within stack cookieMichael Brown2020-07-091-6/+17
| | | | | | | | | | Several of the values used to compute a stack cookie (in the absence of a viable entropy source) will tend to have either all-zeroes or all-ones in the higher order bits. Rotate the values in order to distribute the (minimal) available entropy more evenly. Suggested-by: Pete Beck <pete.beck@ioactive.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Enable stack protection where possibleMichael Brown2020-06-241-0/+62
| | | | | | | | | | | | | | | | | | | Enable -fstack-protector for EFI builds, where binary size is less critical than for BIOS builds. The stack cookie must be constructed immediately on entry, which prohibits the use of any viable entropy source. Construct a cookie by XORing together various mildly random quantities to produce a value that will at least not be identical on each run. On detecting a stack corruption, attempt to call Exit() with an appropriate error. If that fails, then lock up the machine since there is no other safe action that can be taken. The old conditional check for support of -fno-stack-protector is omitted since this flag dates back to GCC 4.1. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Prevent EFI code from being linked in to non-EFI buildsMichael Brown2017-05-191-2/+8
| | | | | | | | Ensure that efi_systab is an undefined symbol in non-EFI builds. In particular, this prevents users from incorrectly enabling IMAGE_EFI in a BIOS build of iPXE. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Work around temporal anomaly encountered during ExitBootServices()Michael Brown2016-12-071-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | EFI provides no clean way for device drivers to shut down in preparation for handover to a booted operating system. The platform firmware simply doesn't bother to call the drivers' Stop() methods. Instead, drivers must register an EVT_SIGNAL_EXIT_BOOT_SERVICES event to be signalled when ExitBootServices() is called, and clean up without any reference to the EFI driver model. Unfortunately, all timers silently stop working when ExitBootServices() is called. Even more unfortunately, and for no discernible reason, this happens before any EVT_SIGNAL_EXIT_BOOT_SERVICES events are signalled. The net effect of this entertaining design choice is that any timeout loops on the shutdown path (e.g. for gracefully closing outstanding TCP connections) may wait indefinitely. There is no way to report failure from currticks(), since the API lazily assumes that the host system continues to travel through time in the usual direction. Work around EFI's violation of this assumption by falling back to a simple free-running monotonic counter. Debugged-by: Maor Dickman <maord@mellanox.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Provide centralised definitions of commonly-used GUIDsMichael Brown2014-08-061-4/+0Star
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Restructure EFI driver modelMichael Brown2014-06-251-80/+42Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | Provide a single instance of EFI_DRIVER_BINDING_PROTOCOL (attached to our image handle); this matches the expectations scattered throughout the EFI specification. Open the underlying hardware device using EFI_OPEN_PROTOCOL_BY_DRIVER and EFI_OPEN_PROTOCOL_EXCLUSIVE, to prevent other drivers from attaching to the same device. Do not automatically connect to devices when being loaded as a driver; leave this task to the platform firmware (or to the user, if loading directly from the EFI shell). When running as an application, forcibly disconnect any existing drivers from devices that we want to control, and reconnect them on exit. Provide a meaningful driver version number (based on the build timestamp), to allow platform firmware to automatically load newer versions of iPXE drivers if multiple drivers are present. Include device paths within debug messages where possible, to aid in debugging. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Do not try to fetch loaded image device path protocolMichael Brown2014-05-201-23/+0Star
| | | | | | | | | | | Some UEFI systems (observed with a Mac Pro) do not provide a loaded image device path protocol. We don't currently use the loaded image device path protocol for anything beyond printing a debug message, so simply remove the code which attempts to fetch it. Reported-by: Matt Woodward <pxematt@woodwardcc.com> Tested-by: Matt Woodward <pxematt@woodwardcc.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Allow for optional protocolsMichael Brown2014-05-191-2/+3
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Allow driver to be unloadedMichael Brown2014-03-101-0/+97
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Perform meaningful error code conversionsMichael Brown2013-04-191-3/+8
| | | | | | | | Exploit the redefinition of iPXE error codes to include a "platform error code" to allow for meaningful conversion of EFI_STATUS values to iPXE errors and vice versa. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Fetch device path for loaded image during initialisationMichael Brown2013-03-271-13/+37
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Provide efi_guid_ntoa() for printing EFI GUIDsMichael Brown2013-03-201-6/+7
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [legal] Update FSF mailing address in GPL licence textsMichael Brown2012-07-201-1/+2
| | | | | Suggested-by: Daniel P. Berrange <berrange@redhat.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Ensure that all drivers are shut down before the OS bootsMichael Brown2011-03-291-0/+29
| | | | | | Reported-by: Itay Gazit <itayg@mellanox.co.il> Suggested-by: Michael R Turner <mikeyt@us.ibm.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Add the "snpnet" driverGeoff Lywood2010-06-021-1/+22
| | | | | | | | | Add a new network driver that consumes the EFI Simple Network Protocol. Also add a bus driver that can find the Simple Network Protocol that iPXE was loaded from; the resulting behavior is similar to the "undionly" driver for BIOS systems. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [build] Rename gPXE to iPXEMichael Brown2010-04-201-2/+2
| | | | | | | | | | | Access to the gpxe.org and etherboot.org domains and associated resources has been revoked by the registrant of the domain. Work around this problem by renaming project from gPXE to iPXE, and updating URLs to match. Also update README, LOG and COPYRIGHTS to remove obsolete information. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [legal] Add a selection of FILE_LICENCE declarationsMichael Brown2009-05-181-0/+2
| | | | | Add FILE_LICENCE declarations to almost all files that make up the various standard builds of gPXE.
* [tables] Redefine methods for accessing linker tablesMichael Brown2009-03-131-14/+2Star
| | | | | | | | | | | | | | | 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.
* [efi] Use elf2efi utility in place of efilinkMichael Brown2009-01-071-0/+122
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.