Accumulate UTF-8 characters in fbcon_putchar(), and require the frame
buffer console's .glyph() method to accept Unicode character values.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Several keyboard layouts define ASCII characters as accessible only
via the AltGr modifier. Add support for this modifier to ensure that
all ASCII characters are accessible.
Experiments suggest that the BIOS console is likely to fail to
generate ASCII characters when the AltGr key is pressed. Work around
this limitation by accepting LShift+RShift (which will definitely
produce an ASCII character) as a synonym for AltGr.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Handle Ctrl and CapsLock key modifiers within key_remap(), to provide
consistent behaviour across different console types.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The key with scancode 86 appears in the position between left shift
and Z on a US keyboard, where it typically fails to exist entirely.
Most US keyboard maps define this nonexistent key as generating "\|",
with the notable exception of "loadkeys" which instead reports it as
generating "<>". Both of these mapping choices duplicate keys that
exist elsewhere in the map, which causes problems for our ASCII-based
remapping mechanism.
Work around these quirks by treating the key as generating "\|" with
the high bit set, and making it subject to remapping. Where the BIOS
generates "\|" as expected, this allows us to remap to the correct
ASCII value.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
To minimise code size, our keyboard mapping works on the basis of
allowing the BIOS to convert the keyboard scancode into an ASCII
character and then remapping the ASCII character.
This causes problems with keyboard layouts such as "fr" that swap the
shifted and unshifted digit keys, since the ASCII-based remapping will
spuriously remap the numeric keypad (which produces the same ASCII
values as the digit keys).
Fix by checking that the keyboard scancode is within the range of keys
that vary between keyboard mappings before attempting to remap the
ASCII character.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
In real mode, code segments are always writable. In protected mode,
code segments can never be writable. The precise implementation of
this attribute differs between CPU generations, with subtly different
behaviour arising on the transitions from protected mode to real mode.
At the point of transition (when the PE bit is cleared in CR0) the
hidden portion of the %cs descriptor will retain whatever attributes
were in place for the protected-mode code segment, including the fact
that the segment is not writable. The immediately following code will
perform a far control flow transfer (such as ljmp or lret) in order to
load a real-mode value into %cs.
On the Pentium and later CPUs, the retained protected-mode attributes
will be ignored for any accesses via %cs while the CPU is in real
mode. A write via %cs will therefore be allowed even though the
hidden portion of the %cs descriptor still describes a non-writable
segment.
On the 486 and earlier CPUs, the retained protected-mode attributes
will not be ignored for accesses via %cs. A write via %cs will
therefore cause a CPU fault. To obtain normal real-mode behaviour
(i.e. a writable %cs descriptor), special logic is added to the ljmp
instruction that populates the hidden portion of the %cs descriptor
with real-mode attributes when a far jump is executed in real mode.
The result is that writes via %cs will cause a CPU fault until the
first ljmp instruction is executed, after which writes via %cs will be
allowed as expected in real mode.
The transition code in libprefix.S currently uses lret to load a
real-mode value into %cs after clearing the PE bit. Experimentation
shows that only the ljmp instruction will work to load real-mode
attributes into the hidden portion of the %cs descriptor: other far
control flow transfers (such as lret, lcall, or int) do not do so.
When running on a 486 or earlier CPU, this results in code within
libprefix.S running with a non-writable code segment after a mode
transition, which in turn results in a CPU fault when real-mode code
in liba20.S attempts to write to %cs:enable_a20_method.
Fix by constructing and executing an ljmp instruction, to trigger the
relevant descriptor population logic on 486 and earlier CPUs. This
ljmp instruction is constructed on the stack, since the .prefix
section may be executing directly from ROM (or from memory that the
BIOS has write-protected in order to emulate an ISA ROM region) and so
cannot be modified.
Reported-by: Nikolai Zhubr <n-a-zhubr@yandex.ru>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
SBAT defines an encoding for security generation numbers stored as a
CSV file within a special ".sbat" section in the signed binary. If a
Secure Boot exploit is discovered then the generation number will be
incremented alongside the corresponding fix.
Platforms may then record the minimum generation number required for
any given product. This allows for an efficient revocation mechanism
that consumes minimal flash storage space (in contrast to the DBX
mechanism, which allows for only a single-digit number of revocation
events to ever take place across all possible signed binaries).
Add SBAT metadata to iPXE EFI binaries to support this mechanism.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow for the DSDT/SSDT signature-scanning and value extraction code
to be reused for extracting a pass-through MAC address.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Commit cd3de55 ("[efi] Record cached DHCPACK from loaded image's
device handle, if present") added the ability for a chainloaded UEFI
iPXE to reuse an IPv4 address and DHCP options previously obtained by
a built-in PXE stack, without needing to perform a second DHCP
request.
Extend this to also record the cached ProxyDHCPOFFER and PXEBSACK
obtained from the EFI_PXE_BASE_CODE_PROTOCOL instance installed on the
loaded image's device handle, if present.
This allows a chainloaded UEFI iPXE to reuse a boot filename or other
options that were provided via a ProxyDHCP or PXE boot server
mechanism, rather than by standard DHCP.
Tested-by: Andreas Hammarskjöld <junior@2PintSoftware.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The ARM versions of the big-integer inline assembly functions include
constraints to indicate that the output value is modified by the
assembly code. These constraints are not present in the equivalent
code for the x86 versions.
As of GCC 11, this results in the compiler reporting that the output
values may be uninitialized.
Fix by including the relevant memory output constraints.
Reported-by: Christian Hesse <mail@eworm.de>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
iPXE will construct CPIO headers for images that have a non-empty
command line, thereby allowing raw images (without CPIO headers) to be
injected into a dynamically constructed initrd. This feature is
currently implemented within the BIOS-only bzImage format support.
Split out the CPIO header construction logic to allow for reuse in
other contexts such as in a UEFI build.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Avoid using the "rdtsc" instruction unless profiling is enabled. This
allows the non-debug build of the UNDI driver to be used on a CPU such
as a 486 that does not support the TSC.
Reported-by: Nikolai Zhubr <n-a-zhubr@yandex.ru>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The decompressor uses the i486 "bswap" instruction, but does not
require any instructions that exist only on i586 or above. Update the
".arch" directive to reflect the requirements of the code as
implemented.
Reported-by: Martin Habets <habetsm.xilinx@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The INT 13 extensions provide a mechanism for accessing disks using
linear (LBA) rather than C/H/S addressing. SAN protocols such as
iSCSI invariably support only linear addresses and so iPXE currently
provides LBA access to all SAN disks (with autodetection and emulation
of an appropriate geometry for C/H/S accesses).
Most BIOSes will not report support for INT 13 extensions for floppy
disk drives, and some operating systems may be confused by a floppy
drive that claims such support.
Minimise surprise by reporting the existence of support for INT 13
extensions only for non-floppy drive numbers. Continue to provide
support for all drive numbers, to avoid breaking operating systems
that may unconditionally use the INT 13 extensions without first
checking for support.
Reported-by: Valdo Toost <vtoost@hot.ee>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
There is no method for obtaining the number of PCI buses when using
PCIAPI_DIRECT, and we therefore currently scan all possible bus
numbers. This can cause a several-second startup delay in some
virtualised environments, since PCI configuration space access will
necessarily require the involvement of the hypervisor.
Ameliorate this situation by defaulting to scanning only a single bus,
and expanding the number of PCI buses to accommodate any subordinate
buses that are detected during enumeration.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The "used" attribute can be applied only to functions or variables,
which prevents the use of __asmcall as a type attribute.
Fix by removing "used" from the definition of __asmcall for i386 and
x86_64 architectures, and adding explicit __used annotations where
necessary.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The ACPI API currently expects platforms to provide access to a single
contiguous ACPI table. Some platforms (e.g. Linux userspace) do not
provide a convenient way to obtain the entire ACPI table, but do
provide access to individual tables.
All iPXE consumers of the ACPI API require access only to individual
tables.
Redefine the internal API to make acpi_find() an API method, with all
existing implementations delegating to the current RSDT-based
implementation.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
When building as a Linux userspace application, iPXE currently
implements its own system calls to the host kernel rather than relying
on the host's C library. The output binary is statically linked and
has no external dependencies.
This matches the general philosophy of other platforms on which iPXE
runs, since there are no external libraries available on either BIOS
or UEFI bare metal. However, it would be useful for the Linux
userspace application to be able to link against host libraries such
as libslirp.
Modify the build process to perform a two-stage link: first picking
out the requested objects in the usual way from blib.a but with
relocations left present, then linking again with a helper object to
create a standard hosted application. The helper object provides the
standard main() entry point and wrappers for the Linux system calls
required by the iPXE Linux drivers and interface code.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow for the possibility of linking to platform libraries for the
Linux userspace build by adding an iPXE-specific symbol prefix.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Recent versions of the GNU assembler (observed with GNU as 2.35 on
Fedora 33) will produce a warning message
Warning: no instruction mnemonic suffix given and no register
operands; using default for `bts'
The operand size affects only the potential range for the bit number.
Since we pass the bit number as an unsigned int, it is already
constrained to 32 bits for both i386 and x86_64.
Silence the assembler warning by specifying an explicit 32-bit operand
size (and thereby matching the choice that the assembler would
otherwise make automatically).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Assume that preservation of the %xmm registers is unnecessary during
installation of iPXE into memory, since this is an operation that by
its nature substantially disrupts large portions of the system anyway
(such as the E820 memory map). This assumption allows us to utilise
the existing CPUID code to check that FXSAVE/FXRSTOR are supported.
Test for support during the call to init_librm and store the flag for
use during subsequent calls to virt_call.
Reduce the scope of TIVOLI_VMM_WORKAROUND to affecting only the call
to check_fxsr(), to reduce #ifdef pollution in the remaining code.
Debugged-by: Johannes Heimansberg <git@jhe.dedyn.io>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The __asmcall declaration has no effect on a void function with no
parameters, but should be included for completeness since the function
is called directly from assembly code.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Provide a generic raw image prefix, which assumes that the iPXE image
has been loaded in its entirety on a paragraph boundary.
The resulting .raw image can be loaded via RPL using an rpld.conf file
such as:
HOST {
ethernet = 00:00:00:00:00:00/6;
FILE {
path="ipxe.raw";
load=0x2000;
};
execute=0x2000;
};
Debugged-by: Johannes Heimansberg <git@jhe.dedyn.io>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
A zero-length initrd file will currently cause an endless loop during
reshuffling as the empty image is repeatedly swapped with itself.
Fix by terminating the inner loop before considering an image as a
candidate to be swapped with itself.
Reported-by: Pico Mitchell <pico@randomapplications.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Split out the portions of cachedhcp.c that can be shared between BIOS
and UEFI (both of which can provide a buffer containing a previously
obtained DHCP packet, and neither of which provide a means to
determine the length of this DHCP packet).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some versions of GNU ld (observed with binutils 2.36 on Arch Linux)
introduce a .note.gnu.property section marked as loadable at a high
address and with non-empty contents. This adds approximately 128MB of
garbage to the BIOS .usb disk images.
Fix by using a custom linker script for the prefix-only binaries such
as the USB disk partition table and MBR, in order to allow unwanted
sections to be explicitly discarded.
Reported-by: Christian Hesse <mail@eworm.de>
Tested-by: Christian Hesse <mail@eworm.de>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The semantics of the assembler's .align directive vary by CPU
architecture. For the ARM builds, it specifies a power of two rather
than a number of bytes. This currently leads to the .einfo entries
(which do not appear in the final binary) having an alignment of 256
bytes for the ARM builds.
Fix by switching to the GNU-specific directive .balign, which is
consistent across architectures
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Several distributions include versions of gcc that are patched to
create position-independent executables by default. These have caused
multiple problems over the years: see e.g. commits fe61f6d ("[build]
Fix compilation when gcc is patched to default to -fPIE -Wl,-pie"),
5de1346 ("[build] Apply the "-fno-PIE -nopie" workaround only to i386
builds"), 7c395b0 ("[build] Use -no-pie on newer versions of gcc"),
and decee20 ("[build] Disable position-independent code for ARM64 EFI
builds").
The build system currently attempts to work around these mildly broken
patched versions of gcc for the i386 and arm64 architectures. This
misses the relatively obscure bin-x86_64-pcbios build platform, which
turns out to also require the same workaround.
Attempt to preempt the next such required workaround by moving the
existing i386 version to apply to all platforms and all architectures,
unless -fpie has been requested explicitly by another Makefile (as is
done by arch/x86_64/Makefile.efi).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Add a few more ABSOLUTE() expressions to convince the FreeBSD linker
that already-absolute symbols are, in fact, absolute.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some versions of objcopy will spuriously complain when asked to
extract the .zinfo section since doing so will nominally alter the
load addresses of the (non-loadable) .bss.* sections.
Avoid these warnings by placing the .zinfo section at the very end of
the load memory address space.
Allocate non-overlapping load memory addresses for the (non-loadable)
.bss.* sections, in the hope of avoiding spurious warnings about
overlapping load addresses.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Consolidate the remaining logic common to initrd_init() and imgmem()
into a shared image_memory() function.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Generalise util/geniso, util/gensdsk, and util/genefidsk to create a
single script util/genfsimg that can be used to build either FAT
filesystem images or ISO images.
Extend the functionality to allow for building multi-architecture UEFI
bootable ISO images and combined BIOS+UEFI images.
For example:
./util/genfsimg -o combined.iso \
bin-x86_64-efi/ipxe.efi \
bin-arm64-efi/ipxe.efi \
bin/ipxe.lkrn
would generate a hybrid image that could be used as a CDROM (or hard
disk or USB key) on legacy BIOS, x86_64 UEFI, or ARM64 UEFI.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The malloc_dma() function allocates memory with specified physical
alignment, and is typically (though not exclusively) used to allocate
memory for DMA.
Rename to malloc_phys() to more closely match the functionality, and
to create name space for functions that specifically allocate and map
DMA-capable buffers.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Define pci_ioremap() as a wrapper around ioremap() that could allow
for a non-zero address translation offset.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
This change fixes the offset used when retrieving the iPXE stack
pointer after a COM32 binary returns. The iPXE stack pointer is saved
at the top of the available memory then the the top of the stack for
the COM32 binary is set just below it. However seven more items are
pushed on the COM32 stack before the entry point is invoked so when
the COM32 binary returns the location of the iPXE stack pointer is 28
(and not 24) bytes above the current stack pointer.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
This caused iPXE to reject images even when enough memory was
available.
Signed-off-by: David Decotigny <ddecotig@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The only remaining use case in iPXE for the CPU direction flag is in
__memcpy_reverse() where it is set to allow the use of "rep movsb" to
perform the memory copy. This matches the equivalent functionality in
the EDK2 codebase, which has functions such as InternalMemCopyMem that
also temporarily set the direction flag in order to use "rep movsb".
As noted in commit d2fb317 ("[crypto] Avoid temporarily setting
direction flag in bigint_is_geq()"), some UEFI implementations are
known to have buggy interrupt handlers that may reboot the machine if
a timer interrupt happens to occur while the direction flag is set.
Work around these buggy UEFI implementations by using the
(unoptimised) generic_memcpy_reverse() on i386 or x86_64 UEFI
platforms.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The UEFI specification states that the calling convention for IA-32
and x64 includes "Direction flag in EFLAGS is clear". This
specification covers only the calling convention used at the point of
calling functions annotated with EFIAPI. The specification explicitly
states that other functions (such as private functions or static
library calls) are not required to follow the UEFI calling
conventions.
The reference EDK2 implementation follows this specification. In
particular, the EDK2 interrupt handlers will clear the direction flag
before calling any EFIAPI functions, and will restore the direction
flag when returning from the interrupt handler. Some EDK2 private
library functions (most notably InternalMemCopyMem) may set the
direction flag temporarily in order to make efficient use of CPU
string operations.
The current implementation of iPXE's bigint_is_geq() for i386 and
x86_64 will similarly set the direction flag temporarily in order to
make efficient use of CPU string operations.
On some UEFI implementations (observed with a Getac RX10 tablet), a
timer interrupt that happens to occur while the direction flag is set
will reboot the machine. This very strongly indicates that the UEFI
timer interrupt handler is failing to clear the direction flag before
performing an affected operation (such as copying a block of memory).
Work around such buggy UEFI implementations by rewriting
bigint_is_geq() to avoid the use of string operations and so obviate
the requirement to temporarily set the direction flag.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some versions of gcc (observed with the cross-compiling gcc 9.3.0 in
Ubuntu 20.04) default to enabling -fPIE. Experimentation shows that
this results in the emission of R_AARCH64_ADR_GOT_PAGE relocation
records for __stack_chk_guard. These relocation types are not
supported by elf2efi.c.
Fix by explicitly disabling position-independent code for ARM64 EFI
builds.
Debugged-by: Antony Messerli <antony@mes.ser.li>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Reduce the size of the USB disk image in the common case that
CONSOLE_INT13 is not enabled.
Originally-implemented-by: Romain Guyard <romain.guyard@mujin.co.jp>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
It is currently not possible to build the all-drivers iPXE binaries
for ARM, since there is no implementation for inb(), outb(), etc.
There is no common standard for accessing I/O space on ARM platforms,
and there are almost no ARM-compatible peripherals that actually
require I/O space accesses.
Provide dummy implementations that behave as though no device is
present (i.e. ignore writes, return all bits high for reads). This is
sufficient to allow the all-drivers binaries to link, and should cause
drivers to behave as though no I/O space peripherals are present in
the system.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
PCI Configuration Space contains fields prog-if at the offset 0x09,
sub-class at the offset 0x0a and base-class at the offset 0x0b (it
respects little endian). PCIR structure uses these fields in the same
order.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow the subsystem IDs to be used when checking for PXE stacks with
broken interrupt support.
Suggested-by: Levi Hsieh <Levi.Hsieh@dell.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Commit 6149e0a ("[librm] Provide symbols for inline code placed into
other sections") may cause build failures due to duplicate label names
if the compiler chooses to duplicate inline assembly code.
Fix by using the "%=" special format string to include a
guaranteed-unique number within the label name.
The "%=" will be expanded only if constraints exist for the inline
assembly. This fix therefore requires that all REAL_CODE() fragments
use a (possibly empty) constraint list.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Provide symbols constructed from the object name and line number for
code fragments placed into alternative sections, such as inline
REAL_CODE() assembly placed into .text16. This simplifies the
debugging task of finding the source code corresponding to a given
instruction pointer.
Note that we cannot use __FUNCTION__ since it is not a preprocessor
macro and so cannot be concatenated with string literals.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
If the underlying PXE stack reports an invalid IRQ number (above
IRQ_MAX), treat this as equivalent to an empty IRQ number and fall
back to using polling mode.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The existence of MMX and SSE is required by the System V x86_64 ABI
and so is assumed by gcc, but these registers are not preserved by our
own interrupt handlers and are unlikely to be preserved by other
context switch handlers in a boot firmware environment.
Explicitly prevent gcc from using MMX or SSE registers to avoid
potential problems due to silent register corruption.
We must remove the %xmm0-%xmm5 clobbers from the x86_64 version of
hv_call() since otherwise gcc will complain about unknown register
names. Theoretically, we should probably add code to explicitly
preserve the %xmm0-%xmm5 registers across a hypercall, in order to
guarantee to external code that these registers remain unchanged. In
practice this is difficult since SSE registers are disabled by
default: for background information see commits 71560d1 ("[librm]
Preserve FPU, MMX and SSE state across calls to virt_call()") and
dd9a14d ("[librm] Conditionalize the workaround for the Tivoli VMM's
SSE garbling").
Signed-off-by: Michael Brown <mcb30@ipxe.org>
We currently perform various min-entropy calculations using build-time
floating-point arithmetic. No floating-point code ends up in the
final binary, since the results are eventually converted to integers
and asserted to be compile-time constants.
Though this mechanism is undoubtedly cute, it inhibits us from using
"-mno-sse" to prevent the use of SSE registers by the compiler.
Fix by using fixed-point arithmetic instead.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow the ACPI power management timer to be used if enabled via
TIMER_ACPI in config/timer.h. This provides an alternative timer on
systems where the standard 8254 PIT is unavailable or unreliable.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
When DEBUG=librm_mgmt is enabled, intercept CPU exceptions and provide
a register and stack dump, then drop to an emergency shell. Exiting
from the shell will almost certainly not work, but this provides an
opportunity to view the register and stack dump and carry out some
basic debugging.
Note that we can intercept only the first 8 CPU exceptions, since a
PXE ROM is not permitted to rebase the PIC.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Using "ld --oformat binary" for mbr.bin and usbdisk.bin seems to cause
segmentation faults on some versions of binutils (observed on Fedora
27). Work around this problem by using ld to create an intermediate
ELF object, followed by objcopy (via the existing %.tmp -> %.bin rule)
to create the final binary.
Note that we cannot simply use a single-stage "objcopy -O binary"
since this will not process the relocation records for x86_64: see
commit 1afcccd ("[build] Do not use "objcopy -O binary" for objects
with relocation records").
Reported-by: Brent S <bts@square-r00t.net>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Add missing FILE_LICENCE declarations to x86_64 headers based on the
corresponding i386 headers (from which the x86_64 headers were
originally derived).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Ensure that all headers (PCI, UNDI, PnP, iPXE) are aligned to at least
four bytes, so that all accesses to header fields will be correctly
aligned even when reading directly from the expansion ROM BAR.
Reported-by: Peter von Konigsmark <peter@exablaze.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
We must not steal ownership from the Gen 2 UEFI firmware, since doing
so will cause an immediate system crash (most likely in the form of a
reboot).
This problem was masked before commit a0f6e75 ("[hyperv] Do not fail
if guest OS ID MSR is already set"), since prior to that commit we
would always fail if we found any non-zero guest OS identity. We now
accept a non-zero previous guest OS identity in order to allow for
situations such as chainloading from iPXE to another iPXE, and as a
prerequisite for commit b91cc98 ("[hyperv] Cope with Windows Server
2016 enlightenments").
A proper fix would be to reverse engineer the UEFI protocols exposed
within the Hyper-V Gen 2 firmware and use these to bind to the VMBus
device representing the network connection, (with the native Hyper-V
driver moved to become a BIOS-only feature).
As an interim solution, fail to initialise the native Hyper-V driver
if we detect the guest OS identity known to be used by the Gen 2 UEFI
firmware. This will cause the standard all-drivers build (ipxe.efi)
to fall back to using the SNP driver.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
EDK2 commit 6440385 ("MdePkg/Include: Add enumeration size checks to
Base.h") enforced the UEFI specification mandate that enums should
always be 32 bits. This revealed a latent bug in iPXE, which does not
build with -fno-short-enums.
Fix by adding -fno-short-enums to CFLAGS for ARM32 EFI builds.
Reported-by: Benjamin S. Allen <bsallen@alcf.anl.gov>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The -mabi option was added in GCC 4.9. Test for the existence of this
option to allow for building with earlier versions of GCC.
Reported-by: Benjamin S. Allen <bsallen@alcf.anl.gov>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
For some CPUID leaves (e.g. %eax=0x00000004), the result depends on
the input value of %ecx. Allow this subfunction number to be
specified as a parameter to the cpuid() wrapper.
The subfunction number is exposed via the ${cpuid/...} settings
mechanism using the syntax
${cpuid/<subfunction>.0x40.<register>.<function>}
e.g.
${cpuid/0.0x40.0.0x0000000b}
${cpuid/1.0x40.0.0x0000000b}
to retrieve the CPU topology information.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some distributions patch gcc to generate position independent
executables by default. We currently include a workaround to check
for this and to add -fno-PIE -nopie to CFLAGS if required.
Newer patched versions of gcc require -fno-PIE -no-pie instead. Check
for both variants.
Reported-by: Nathan Rennie-Waldock <nathan.renniewaldock@gmail.com>
Originally-fixed-by: Markos Chandras <mchandras@suse.de>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
When booting from a hard disk image (e.g. bin/ipxe.usb) within an
emulator such as QEMU, the disk may not exist beyond the end of the
image. Limit all reads to the length of the image to avoid spurious
errors when loading the iPXE image.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
An "enlightened" external bootloader (such as Windows Server 2016's
winload.exe) may take ownership of the Hyper-V connection before all
INT 13 operations have been completed. When this happens, all VMBus
devices are implicitly closed and we are left with a non-functional
network connection.
Detect when our Hyper-V connection has been lost (by checking the
SynIC message page MSR). Reclaim ownership of the Hyper-V connection
and reestablish any VMBus devices, without disrupting any existing
iPXE state (such as IPv4 settings attached to the network device).
Windows Server 2016 will not cleanly take ownership of an active
Hyper-V connection. Experimentation shows that we can quiesce by
resetting only the SynIC message page MSR; this results in a
successful SAN boot (on a Windows 2012 R2 physical host). Choose to
quiesce by resetting (almost) all MSRs, in the hope that this will be
more robust against corner cases such as a stray synthetic interrupt
occurring during the handover.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some older operating systems (e.g. RHEL6) use a non-default filename
on the root disk and rely on setting an EFI variable to point to the
bootloader. This does not work when performing a SAN boot on a
machine where the EFI variable is not present.
Fix by allowing a non-default filename to be specified via the
"sanboot --filename" option or the "san-filename" setting. For
example:
sanboot --filename \efi\redhat\grub.efi \
iscsi:192.168.0.1::::iqn.2010-04.org.ipxe.demo:rhel6
or
option ipxe.san-filename code 188 = string;
option ipxe.san-filename "\\efi\\redhat\\grub.efi";
option root-path "iscsi:192.168.0.1::::iqn.2010-04.org.ipxe.demo:rhel6";
Originally-implemented-by: Vishvananda Ishaya Abrams <vish.ishaya@oracle.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Describe all SAN devices via ACPI tables such as the iBFT. For tables
that can describe only a single device (i.e. the aBFT and sBFT), one
table is installed per device. For multi-device tables (i.e. the
iBFT), all devices are described in a single table.
An underlying SAN device connection may be closed at the time that we
need to construct an ACPI table. We therefore introduce the concept
of an "ACPI descriptor" which enables the SAN boot code to maintain an
opaque pointer to the underlying object, and an "ACPI model" which can
build tables from a list of such descriptors. This separates the
lifecycles of ACPI descriptions from the lifecycles of the block
device interfaces, and allows for construction of the ACPI tables even
if the block device interface has been closed.
For a multipath SAN device, iPXE will wait until sufficient
information is available to describe all devices but will not wait for
all paths to connect successfully. For example: with a multipath
iSCSI boot iPXE will wait until at least one path has become available
and name resolution has completed on all other paths. We do this
since the iBFT has to include IP addresses rather than DNS names. We
will commence booting without waiting for the inactive paths to either
become available or close; this avoids unnecessary boot delays.
Note that the Linux kernel will refuse to accept an iBFT with more
than two NIC or target structures. We therefore describe only the
NICs that are actually required in order to reach the described
targets. Any iBFT with at most two targets is therefore guaranteed to
describe at most two NICs.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The INT13 console type (CONSOLE_INT13) autodetects at initialisation
time a magic partition to be used for logging iPXE console output. If
the INT13 drive number mapping is subsequently changed (e.g. because
iPXE was used to perform a SAN boot), then the console logging output
will be written to the incorrect disk.
Fix by recording the INT13 vector at initialisation time, and using
this original vector to emulate INT13 calls for all subsequent
accesses. This should be robust against drive remapping performed
either by ourselves or by another bootloader (e.g. a chainloaded
undionly.kpxe which then performs a SAN boot).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some partition tables have partitions that are not aligned to a
cylinder boundary, which confuses the current geometry guessing logic.
Enhance the existing logic to ensure that we never reduce our guesses
for the number of heads or sectors per track, and add extra logic to
calculate the exact number of sectors per track if we find a partition
that starts within cylinder zero.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Add basic support for multipath block devices. The "sanboot" and
"sanhook" commands now accept a list of SAN URIs. We open all URIs
concurrently. The first connection to become available for issuing
block device commands is marked as the active path and used for all
subsequent commands; all other connections are then closed. Whenever
the active path fails, we reopen all URIs and repeat the process.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
As of commit 10d19bd ("[pxe] Always retrieve cached DHCPACK and apply
to relevant network device"), the UNDI driver has been the only user
of pxeparent_call(). Remove the unnecessary layer of abstraction by
refactoring this code back into undinet.c, and fix the ability of
undiisr.S to fall back to chaining to the original handler if we were
unable to unhook our own ISR.
This effectively reverts commit 337e1ed ("[pxe] Separate parent PXE
API caller from UNDINET driver").
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The concept of the SAN drive number is meaningful only in a BIOS
environment, where it represents the INT13 drive number (0x80 for the
first hard disk). We retain this concept in a UEFI environment to
allow for a simple way for iPXE commands to refer to SAN drives.
Centralise the concept of the default drive number, since it is shared
between all supported environments.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
INT 13 calls return a status value via %ah, with CF set if %ah is
non-zero (indicating an error). Our wrappers zero the whole of %ax if
CF is clear, to allow C code (which has no easy access to CF) to
simply test for a non-zero status to detect an error.
The current code assigns the returned status to a uint8_t, effectively
testing %al rather than %ah. Fix by treating the returned status as a
uint16_t instead.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Avoid using a zero sector count to guess the disk geometry, since that
would result in a division by zero when calculating the number of
cylinders.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
When running on AMD platforms, the legacy hardware emulation is
extremely unreliable. In particular, the IRQ0 timer interrupt is
likely to simply stop working, resulting in a total failure of any
code that relies on timers (such as DHCP retransmission attempts).
Work around this by using the 10MHz time counter provided by Hyper-V
via an MSR. (This timer can be tested in KVM via the command-line
option "-cpu host,hv_time".)
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow the active timer (providing udelay() and currticks()) to be
selected at runtime based on probing during the INIT_EARLY stage of
initialisation.
TICKS_PER_SEC is now a fixed compile-time constant for all builds, and
is independent of the underlying clock tick rate. We choose the value
1024 to allow multiplications and divisions on seconds to be converted
to bit shifts.
TICKS_PER_MS is defined as 1, allowing multiplications and divisions
on milliseconds to be omitted entirely. The 2% inaccuracy in this
definition is negligible when using the standard BIOS timer (running
at around 18.2Hz).
TIMER_RDTSC now checks for a constant TSC before claiming to be a
usable timer. (This timer can be tested in KVM via the command-line
option "-cpu host,+invtsc".)
Signed-off-by: Michael Brown <mcb30@ipxe.org>
This code largely inspired by tap.c. Allows for testing iPXE on real
NICs from within Linux. For example:
make bin-x86_64-linux/af_packet.linux
valgrind ./bin-x86_64-linux/af_packet.linux --net af_packet,if=eth3
Tested as x86_64 and i386 binary.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
When searching for an UNDI ROM to match against a PCI device, search
in order of increasing ROM address (within the 128kB BIOS option ROM
area). This is likely (though not guaranteed) to match the order of
the original enumeration performed by the BIOS, which is in turn
likely to match the order of enumeration on the PCI bus.
Since we load at most one UNDI ROM, the net result is that we increase
our chances of loading the ROM corresponding to the selected PCI
device (rather than loading a ROM corresponding to a higher-numbered
PCI device with the same vendor and device IDs.)
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The "progress" macro can be used only from within the .prefix section.
At the point of calling relocate(), we are running in .text16 and so
the near call to print_message() will end up calling a random function
somewhere in .text16.
Interestingly, this problem has remained unnoticed for some time. It
is rare to build with DEBUG=libprefix. In the few cases that it has
been used during development, the randomly selected function in
.text16 seems to have been a harmless no-op with no visible
side-effects (beyond the unnoticed failure to print the "relocate"
progress message).
Fix by removing the futile attempt to print a progress message before
calling relocate().
Reported-by: Raed Salem <raeds@mellanox.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Fix the <NULL> driver name reported by "ifstat" when using the undipci
driver (due to the unnecessary extra device node inserted as a child
of the PCI device).
Remove the "UNDI-" prefix from device names since the driver name is
also now visible via "ifstat", and tidy up the device name to match
the format used by standard PCI devices.
The output from "ifstat" now resembles:
iPXE> ifstat
net0: 52:54:00:12:34:56 using undipci on 0000:00:03.0
iPXE> ifstat
net0: 52:54:00:12:34:56 using undionly on 0000:00:03.0
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The UNDI loader entry point is very likely to be called after POST,
when there is a high chance that the PMM-allocated image source area
and decompression area have been reused by something else.
In particular, using an iPXE .iso to test a separate iPXE ROM's UNDI
loader entry point in a qemu VM is likely to crash. SeaBIOS allocates
PMM blocks from close to the top of memory and so these blocks have a
high chance of colliding with the runtime addresses subsequently
chosen by the non-ROM iPXE by scanning the INT 15,e820 memory map.
The standard romprefix.S has no choice about relying on the
PMM-allocated image source area, since it has no other way to retrieve
its compressed payload.
In mromprefix.S, the image source area functions only as an optional
buffer used to avoid repeated reads from the (potentially slow)
expansion ROM BAR by the decompression code. We can therefore always
set %esi=0 when calling install_prealloc from the UNDI loader entry
point, and simply fall back to reading directly from the expansion ROM
BAR.
We can always set %edi=0 when calling install_prealloc from the UNDI
loader entry point. This will behave as though the decompression area
PMM allocation failed, and will therefore use INT 15,88 to find a
temporary decompression area somewhere close to 64MB. This is by no
means guaranteed to be safe from collisions, but it's probably safer
on balance than the PMM-allocated address.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allocate base memory (by decreasing the free base memory counter)
before calling the UNDI loader entry point, to minimise surprises for
the UNDI loader code.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Commit 71560d1 ("[librm] Preserve FPU, MMX and SSE state across calls
to virt_call()") added FXSAVE and FXRSTOR instructions to iPXE. In
KVM virtual machines, these instructions execute fine as long as the
host CPU supports the "unrestricted_guest" feature (that is, it can
virtualize big real mode natively). On older host CPUs however, KVM
has to emulate big real mode, and it currently doesn't implement
FXSAVE emulation.
Upstream QEMU rebuilt iPXE at commit 0418631 ("[thunderx] Fix
compilation with older versions of gcc") which is a descendant of
commit 71560d1 (see above).
This was done in QEMU commit ffdc5a2 ("ipxe: update submodule from
4e03af8ec to 041863191"). The resultant binaries were bundled with
the QEMU v2.7.0 release; see QEMU commit c52125a ("ipxe: update
prebuilt binaries").
This distributed the iPXE workaround for the Tivoli VMM bug to a
number of KVM users with old host CPUs, causing KVM emulation failures
(guest crashes) for them while netbooting.
Make the FXSAVE and FXRSTOR instructions conditional on a new feature
test macro called TIVOLI_VMM_WORKAROUND. Define the macro by default.
There is prior art for an assembly file including config/general.h:
see arch/x86/prefix/romprefix.S. Also, TIVOLI_VMM_WORKAROUND seems to
be a good fit for the "Obscure configuration options" section in
config/general.h.
Cc: Bandan Das <bsd@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Greg <rollenwiese@yahoo.com>
Cc: Michael Brown <mcb30@ipxe.org>
Cc: Michael Prokop <launchpad@michael-prokop.at>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Pickford <arch@netremedies.ca>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Ref: https://bugs.archlinux.org/task/50778
Ref: https://bugs.launchpad.net/qemu/+bug/1623276
Ref: https://bugzilla.proxmox.com/show_bug.cgi?id=1182
Ref: https://bugzilla.redhat.com/show_bug.cgi?id=1356762
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The initrd_addr_max field represents the highest byte address that may
be used to hold initrd images, and is therefore almost certainly not
aligned to a page boundary: a typical value might be 0x7fffffff.
Fix the address calculations to ensure that the initrd images are
always aligned to a page boundary.
Reported-by: Sitsofe Wheeler <sitsofe@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The ACPI power off sequence may not take effect immediately. Delay
for one second, to eliminate potentially confusing log messages such
as "Could not power off: Error 0x43902001 (http://ipx".
Reported-by: Leonid Vasetsky <leonidv@velostrata.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown
Dentcho Ludmilov Bankov
David Decotigny
Petr Borsodi
Laszlo Ersek