efi_printk can now handle the UTF-16 filename, so print it using efi_err
instead of a separate efi_char16_puts call.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-23-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
In order to be able to use the UTF-16 support added to vsprintf in the
previous commit, enhance efi_puts to decode UTF-8 into UTF-16. Invalid
UTF-8 encodings are passed through unchanged.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-22-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Add the required typedefs etc for using con_in's simple text input
protocol, and for using the boottime event services.
Also add the prototype for the "stall" boot service.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-19-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Use the efi_printk function in efi_info/efi_err, and add efi_debug. This
allows formatted output at different log levels.
Add the notion of a loglevel instead of just quiet/not-quiet, and
parse the efi=debug kernel parameter in addition to quiet.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200520170223.GA3333632@rani.riverdale.lan/
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
If we get an invalid conversion specifier, bail out instead of trying to
fix it up. The format string likely has a typo or assumed we support
something that we don't, in either case the remaining arguments won't
match up with the remaining format string.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-16-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Consolidate the actual output of the formatted text into one place.
Fix a couple of edge cases:
1. If 0 is printed with a precision of 0, the printf specification says
that nothing should be output, with one exception (2b).
2. The specification for octal alternate format (%#o) adds the leading
zero not as a prefix as the 0x for hexadecimal is, but by increasing
the precision if necessary to add the zero. This means that
a. %#.2o turns 8 into "010", but 1 into "01" rather than "001".
b. %#.o prints 0 as "0" rather than "", unlike the situation for
decimal, hexadecimal and regular octal format, which all output an
empty string.
Reduce the space allocated for printing a number to the maximum actually
required (22 bytes for a 64-bit number in octal), instead of the 66
bytes previously allocated.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-15-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
A negative precision should be ignored completely, and the presence of a
valid precision should turn off the 0 flag.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-10-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Move flags parsing code out into a helper function.
The '%%' case can be handled up front: it is not allowed to have flags,
width etc.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-9-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Support 'll' qualifier for long long by copying the decimal printing
code from lib/vsprintf.c. For simplicity, the 32-bit code is used on
64-bit architectures as well.
Support 'hh' qualifier for signed/unsigned char type integers.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-8-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reclaim the bloat from the addition of printf by optimizing the stub for
size. With gcc 9, the text size of the stub is:
ARCH before +printf -Os
arm 35197 37889 34638
arm64 34883 38159 34479
i386 18571 21657 17025
x86_64 25677 29328 22144
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-6-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Copy vsprintf from arch/x86/boot/printf.c to get a simple printf
implementation.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-5-nivedita@alum.mit.edu
[ardb: add some missing braces in if...else clauses]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Use a buffer to convert the string to UTF-16. This will reduce the
number of firmware calls required to print the string from one per
character to one per string in most cases.
Cast the input char to unsigned char before converting to efi_char16_t
to avoid sign-extension in case there are any non-ASCII characters in
the input.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-4-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
These functions do not support formatting, unlike printk. Rename them to
puts to make that clear.
Move the implementations of these two functions next to each other.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-3-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Add #include directives for include files that efistub.h depends on,
instead of relying on them having been included by the C source files
prior to efistub.h.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-2-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
To help the compiler figure out that efi_printk() will not modify
the string it is given, make the input argument type const char*.
While at it, simplify the implementation as well.
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
When building the x86 EFI stub with Clang, the libstub Makefile rules
that manipulate the ELF object files may throw an error like:
STUBCPY drivers/firmware/efi/libstub/efi-stub-helper.stub.o
strip: drivers/firmware/efi/libstub/efi-stub-helper.stub.o: Failed to find link section for section 10
objcopy: drivers/firmware/efi/libstub/efi-stub-helper.stub.o: Failed to find link section for section 10
This is the result of a LLVM feature [0] where symbol references are
stored in a LLVM specific .llvm_addrsig section in a non-transparent way,
causing generic ELF tools such as strip or objcopy to choke on them.
So force the compiler not to emit these sections, by passing the
appropriate command line option.
[0] https://sourceware.org/bugzilla/show_bug.cgi?id=23817
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Sami Tolvanen <samitolvanen@google.com>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Fangrui Song <maskray@google.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Commit
22090f84bc ("efi/libstub: unify EFI call wrappers for non-x86")
refactored the macros that are used to provide wrappers for mixed-mode
calls on x86, allowing us to boot a 64-bit kernel on 32-bit firmware.
Unfortunately, this broke mixed mode boot due to the fact that
efi_is_native() is not a macro on x86.
All of these macros should go together, so rather than testing each one
to see if it is defined, condition the generic macro definitions on a
new ARCH_HAS_EFISTUB_WRAPPERS, and remove the wrapper definitions on x86
as well if CONFIG_EFI_MIXED is not enabled.
Fixes: 22090f84bc ("efi/libstub: unify EFI call wrappers for non-x86")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200504150248.62482-1-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
efi_parse_options can fail if it is unable to allocate space for a copy
of the command line. Check the return value to make sure it succeeded.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-12-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Factor out the initrd loading into a common function that can be called
both from the generic efi-stub.c and the x86-specific x86-stub.c.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-10-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Rename pr_efi to efi_info and pr_efi_err to efi_err to make it more
obvious that they are part of the EFI stub and not generic printk infra.
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-4-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
In several places 64-bit values need to be split up into two 32-bit
fields, in order to be backward-compatible with the old 32-bit ABIs.
Instead of open-coding this, add a helper function to set a 64-bit value
as two 32-bit fields.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-3-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
struct boot_params is only 4096 bytes, not 16384. Fix this by using
sizeof(struct boot_params) instead of hardcoding the incorrect value.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-2-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Commit:
cf6b836648 ("efi/libstub: Make initrd file loader configurable")
inadvertently disabled support on x86 for loading an initrd passed via
the initrd= option on the kernel command line.
Add X86 to the newly introduced Kconfig option's title and depends
declarations, so it gets enabled by default, as before.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: linux-efi@vger.kernel.org
Instead of making match_config_table() test its table_types pointer for
NULL-ness, omit the call entirely if no arch_tables pointer was provided
to efi_config_parse_tables().
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Increase legibility by adding whitespace to the efi_config_table_type_t
arrays that describe which EFI config tables we look for when going over
the firmware provided list. While at it, replace the 'name' char pointer
with a char array, which is more space efficient on relocatable 64-bit
kernels, as it avoids a 8 byte pointer and the associated relocation
data (24 bytes when using RELA format)
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
We no longer need to take special care when using global variables
in the EFI stub, so switch to a simple symbol reference for efi_is64.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
The practice of using __pure getter functions to access global
variables in the EFI stub dates back to the time when we had to
carefully prevent GOT entries from being emitted, because we
could not rely on the toolchain to do this for us.
Today, we use the hidden visibility pragma for all EFI stub source
files, which now all live in the same subdirectory, and we apply a
sanity check on the objects, so we can get rid of these getter
functions and simply refer to global data objects directly.
So switch over the remaining boolean variables carrying options set
on the kernel command line.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
The practice of using __pure getter functions to access global
variables in the EFI stub dates back to the time when we had to
carefully prevent GOT entries from being emitted, because we
could not rely on the toolchain to do this for us.
Today, we use the hidden visibility pragma for all EFI stub source
files, which now all live in the same subdirectory, and we apply a
sanity check on the objects, so we can get rid of these getter
functions and simply refer to global data objects directly.
Start with efi_system_table(), and convert it into a global variable.
While at it, make it a pointer-to-const, because we can.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Now that both arm and x86 are using the linker script to place the EFI
stub's global variables in the correct section, remove __efistub_global.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20200416151227.3360778-4-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Instead of using __efistub_global to force variables into the .data
section, leave them in the .bss but pull the EFI stub's .bss section
into .data in the linker script for the compressed kernel.
Add relocation checking for x86 as well to catch non-PC-relative
relocations that require runtime processing, since the EFI stub does not
do any runtime relocation processing.
This will catch, for example, data relocations created by static
initializers of pointers.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200416151227.3360778-3-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Instead of using __efistub_global to force variables into the .data
section, leave them in the .bss but pull the EFI stub's .bss section
into .data in the linker script for the compressed kernel.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20200416151227.3360778-2-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Move efi_relocate_kernel() into a separate source file, so that it
only gets pulled into builds for architectures that use it. Since
efi_relocate_kernel() is the only user of efi_low_alloc(), let's
move that over as well.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
It is no longer necessary to locate the kernel as low as possible in
physical memory, and so we can switch from efi_low_alloc() [which is
a rather nasty concoction on top of GetMemoryMap()] to a new helper
called efi_allocate_pages_aligned(), which simply rounds up the size
to account for the alignment, and frees the misaligned pages again.
So considering that the kernel can live anywhere in the physical
address space, as long as its alignment requirements are met, let's
switch to efi_allocate_pages_aligned() to allocate the pages.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Break out the code to create an aligned page allocation from mem.c
and move it into a function efi_allocate_pages_aligned() in alignedmem.c.
Update efi_allocate_pages() to invoke it unless the minimum alignment
equals the EFI page size (4 KB), in which case the ordinary page
allocator is sufficient. This way, efi_allocate_pages_aligned() will
only be pulled into the build if it is actually being used (which will
be on arm64 only in the immediate future)
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
The KASLR code path in the arm64 version of the EFI stub incorporates
some overly complicated logic to randomly allocate a region of the right
alignment: there is no need to randomize the placement of the kernel
modulo 2 MiB separately from the placement of the 2 MiB aligned allocation
itself - we can simply follow the same logic used by the non-randomized
placement, which is to allocate at the correct alignment, and only take
TEXT_OFFSET into account if it is not a round multiple of the alignment.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
