The implementation of efi_high_alloc() uses a complicated way of
traversing the memory map to find an available region that is located
as close as possible to the provided upper limit, and calls AllocatePages
subsequently to create the allocation at that exact address.
This is precisely what the EFI_ALLOCATE_MAX_ADDRESS allocation type
argument to AllocatePages() does, and considering that EFI_ALLOC_ALIGN
only exceeds EFI_PAGE_SIZE on arm64, let's use AllocatePages() directly
and implement the alignment using code that the compiler can remove if
it does not exceed EFI_PAGE_SIZE.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Create a new source file mem.c to keep the routines involved in memory
allocation and deallocation and manipulation of the EFI memory map.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
The arm64 kernel no longer requires the FDT blob to fit inside a
naturally aligned 2 MB memory block, so remove the code that aligns
the allocation to 2 MB.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Instead of setting the visibility pragma for a small set of symbol
declarations that could result in absolute references that we cannot
support in the stub, declare hidden visibility for all code in the
EFI stub, which is more robust and future proof.
To ensure that the #pragma is taken into account before any other
includes are processed, put it in a header file of its own and
include it via the compiler command line using the -include option.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
The UEFI spec defines (and deprecates) a misguided and shortlived
memory protection feature that is based on splitting memory regions
covering PE/COFF executables into separate code and data regions,
without annotating them as belonging to the same executable image.
When the OS assigns the virtual addresses of these regions, it may
move them around arbitrarily, without taking into account that the
PE/COFF code sections may contain relative references into the data
sections, which means the relative placement of these segments has
to be preserved or the executable image will be corrupted.
The original workaround on arm64 was to ensure that adjacent regions
of the same type were mapped adjacently in the virtual mapping, but
this requires sorting of the memory map, which we would prefer to
avoid.
Considering that the native physical mapping of the PE/COFF images
does not suffer from this issue, let's preserve it at runtime, and
install it as the virtual mapping as well.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Expose efi_entry() as the PE/COFF entrypoint directly, instead of
jumping into a wrapper that fiddles with stack buffers and other
stuff that the compiler is much better at. The only reason this
code exists is to obtain a pointer to the base of the image, but
we can get the same value from the loaded_image protocol, which
we already need for other reasons anyway.
Update the return type as well, to make it consistent with what
is required for a PE/COFF executable entrypoint.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Add an option to disable the busmaster bit in the control register on
all PCI bridges before calling ExitBootServices() and passing control
to the runtime kernel. System firmware may configure the IOMMU to prevent
malicious PCI devices from being able to attack the OS via DMA. However,
since firmware can't guarantee that the OS is IOMMU-aware, it will tear
down IOMMU configuration when ExitBootServices() is called. This leaves
a window between where a hostile device could still cause damage before
Linux configures the IOMMU again.
If CONFIG_EFI_DISABLE_PCI_DMA is enabled or "efi=disable_early_pci_dma"
is passed on the command line, the EFI stub will clear the busmaster bit
on all PCI bridges before ExitBootServices() is called. This will
prevent any malicious PCI devices from being able to perform DMA until
the kernel reenables busmastering after configuring the IOMMU.
This option may cause failures with some poorly behaved hardware and
should not be enabled without testing. The kernel commandline options
"efi=disable_early_pci_dma" or "efi=no_disable_early_pci_dma" may be
used to override the default. Note that PCI devices downstream from PCI
bridges are disconnected from their drivers first, using the UEFI
driver model API, so that DMA can be disabled safely at the bridge
level.
[ardb: disconnect PCI I/O handles first, as suggested by Arvind]
Co-developed-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Matthew Garrett <matthewgarrett@google.com>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20200103113953.9571-18-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Introduce the ability to define macros to perform argument translation
for the calls that need it, and define them for the boot services that
we currently use.
When calling 32-bit firmware methods in mixed mode, all output
parameters that are 32-bit according to the firmware, but 64-bit in the
kernel (ie OUT UINTN * or OUT VOID **) must be initialized in the
kernel, or the upper 32 bits may contain garbage. Define macros that
zero out the upper 32 bits of the output before invoking the firmware
method.
When a 32-bit EFI call takes 64-bit arguments, the mixed-mode call must
push the two 32-bit halves as separate arguments onto the stack. This
can be achieved by splitting the argument into its two halves when
calling the assembler thunk. Define a macro to do this for the
free_pages boot service.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Matthew Garrett <mjg59@google.com>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20200103113953.9571-17-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Drop leading underscores and use bool not int for true/false
variables set on the command line.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-25-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The macros efi_call_early and efi_call_runtime are used to call EFI
boot services and runtime services, respectively. However, the naming
is confusing, given that the early vs runtime distinction may suggest
that these are used for calling the same set of services either early
or late (== at runtime), while in reality, the sets of services they
can be used with are completely disjoint, and efi_call_runtime is also
only usable in 'early' code.
So do a global sweep to replace all occurrences with efi_bs_call or
efi_rt_call, respectively, where BS and RT match the idiom used by
the UEFI spec to refer to boot time or runtime services.
While at it, use 'func' as the macro parameter name for the function
pointers, which is less likely to collide and cause weird build errors.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-24-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
None of the definitions of the efi_table_attr() still refer to
their 'table' argument so let's get rid of it entirely.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-23-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
After refactoring the mixed mode support code, efi_call_proto()
no longer uses its protocol argument in any of its implementation,
so let's remove it altogether.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-22-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Mixed mode translates calls from the 64-bit kernel into the 32-bit
firmware by wrapping them in a call to a thunking routine that
pushes a 32-bit word onto the stack for each argument passed to the
function, regardless of the argument type. This works surprisingly
well for most services and protocols, with the exception of ones that
take explicit 64-bit arguments.
efi_free() invokes the FreePages() EFI boot service, which takes
a efi_physical_addr_t as its address argument, and this is one of
those 64-bit types. This means that the 32-bit firmware will
interpret the (addr, size) pair as a single 64-bit quantity, and
since it is guaranteed to have the high word set (as size > 0),
it will always fail due to the fact that EFI memory allocations are
always < 4 GB on 32-bit firmware.
So let's fix this by giving the thunking code a little hand, and
pass two values for the address, and a third one for the size.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-21-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We have a helper efi_system_table() that gives us the address of the
EFI system table in memory, so there is no longer point in passing
it around from each function to the next.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-20-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
As a first step towards getting rid of the need to pass around a function
parameter 'sys_table_arg' pointing to the EFI system table, remove the
references to it in the printing code, which is represents the majority
of the use cases.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-19-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use a single implementation for efi_char16_printk() across all
architectures.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-17-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The efi_call macros on ARM have a dependency on a variable 'sys_table_arg'
existing in the scope of the macro instantiation. Since this variable
always points to the same data structure, let's create a global getter
for it and use that instead.
Note that the use of a global variable with external linkage is avoided,
given the problems we had in the past with early processing of the GOT
tables.
While at it, drop the redundant casts in the efi_table_attr and
efi_call_proto macros.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-16-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The EFI file I/O routines built on top of the file I/O firmware
services are incompatible with mixed mode, so there is no need
to obfuscate them by using protocol wrappers whose only purpose
is to hide the mixed mode handling. So let's switch to plain
indirect calls instead.
This also means we can drop the mixed_mode aliases from the various
types involved.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-15-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Annotate all the firmware routines (boot services, runtime services and
protocol methods) called in the boot context as __efiapi, and make
it expand to __attribute__((ms_abi)) on 64-bit x86. This allows us
to use the compiler to generate the calls into firmware that use the
MS calling convention instead of the SysV one.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-13-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We will soon remove another level of pointer casting, so let's make
sure all type handling involving firmware calls at boot time is correct.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-12-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Now that we have incorporated the mixed mode protocol definitions
into the native ones using unions, we no longer need the separate
32/64 bit struct definitions, with the exception of the EFI system
table definition and the boot services, runtime services and
configuration table definitions. So drop the unused ones.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-11-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently, we support mixed mode by casting all boot time firmware
calls to 64-bit explicitly on native 64-bit systems, and to 32-bit
on 32-bit systems or 64-bit systems running with 32-bit firmware.
Due to this explicit awareness of the bitness in the code, we do a
lot of casting even on generic code that is shared with other
architectures, where mixed mode does not even exist. This casting
leads to loss of coverage of type checking by the compiler, which
we should try to avoid.
So instead of distinguishing between 32-bit vs 64-bit, distinguish
between native vs mixed, and limit all the nasty casting and
pointer mangling to the code that actually deals with mixed mode.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-10-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In preparation of moving to a native vs. mixed mode split rather than a
32 vs. 64 bit split when it comes to invoking EFI firmware services,
update all the native protocol definitions and redefine them as unions
containing an anonymous struct for the native view and a struct called
'mixed_mode' describing the 32-bit view of the protocol when called from
64-bit code.
While at it, flesh out some PCI I/O member definitions that we will be
needing shortly.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-9-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Iterating over a EFI handle array is a bit finicky, since we have
to take mixed mode into account, where handles are only 32-bit
while the native efi_handle_t type is 64-bit.
So introduce a helper, and replace the various occurrences of
this pattern.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-8-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use efi_table_attr macro to deal with 32/64-bit firmware using the same
source code.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-5-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use typedef for the GOP structures, in anticipation of unifying
32/64-bit code. Also use more appropriate types in the non-bitness
specific structures for the framebuffer address and pointers.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-4-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit:
0d95981438 ("x86: efi/random: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table")
causes the drivers/efi/libstub/random.c code to get used on x86 for the first time.
But this code was not written with EFI mixed mode in mind (running a 64
bit kernel on 32 bit EFI firmware), this causes the kernel to crash during
early boot when running in mixed mode.
The problem is that in mixed mode pointers are 64 bit, but when running on
a 32 bit firmware, EFI calls which return a pointer value by reference only
fill the lower 32 bits of the passed pointer, leaving the upper 32 bits
uninitialized which leads to crashes.
This commit fixes this by initializing pointers which are passed by
reference to EFI calls to NULL before passing them, so that the upper 32
bits are initialized to 0.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Fixes: 0d95981438 ("x86: efi/random: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table")
Link: https://lkml.kernel.org/r/20191224132909.102540-3-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
efi_graphics_output_protocol::query_mode() returns info in
callee-allocated memory which must be freed by the caller, which
we aren't doing.
We don't actually need to call query_mode() in order to obtain the
info for the current graphics mode, which is already there in
gop->mode->info, so just access it directly in the setup_gop32/64()
functions.
Also nothing uses the size of the info structure, so don't update the
passed-in size (which is the size of the gop_handle table in bytes)
unnecessarily.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Bhupesh Sharma <bhsharma@redhat.com>
Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191206165542.31469-5-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If we've found a usable instance of the Graphics Output Protocol
(GOP) with a framebuffer, it is possible that one of the later EFI
calls fails while checking if any support console output. In this
case status may be an EFI error code even though we found a usable
GOP.
Fix this by explicitly return EFI_SUCCESS if a usable GOP has been
located.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Bhupesh Sharma <bhsharma@redhat.com>
Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191206165542.31469-4-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If we don't find a usable instance of the Graphics Output Protocol
(GOP) because none of them have a framebuffer (i.e. they were all
PIXEL_BLT_ONLY), but all the EFI calls succeeded, we will return
EFI_SUCCESS even though we didn't find a usable GOP.
Fix this by explicitly returning EFI_NOT_FOUND if no usable GOPs are
found, allowing the caller to probe for UGA instead.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Bhupesh Sharma <bhsharma@redhat.com>
Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191206165542.31469-3-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
- Update the ACPICA code in the kernel to upstream revision 20191018
including:
* Fixes for Clang warnings (Bob Moore).
* Fix for possible overflow in get_tick_count() (Bob Moore).
* Introduction of acpi_unload_table() (Bob Moore).
* Debugger and utilities updates (Erik Schmauss).
* Fix for unloading tables loaded via configfs (Nikolaus Voss).
- Add support for EFI specific purpose memory to optionally allow
either application-exclusive or core-kernel-mm managed access to
differentiated memory (Dan Williams).
- Fix and clean up processing of the HMAT table (Brice Goglin,
Qian Cai, Tao Xu).
- Update the ACPI EC driver to make it work on systems with
hardware-reduced ACPI (Daniel Drake).
- Always build in support for the Generic Event Device (GED) to
allow one kernel binary to work both on systems with full
hardware ACPI and hardware-reduced ACPI (Arjan van de Ven).
- Fix the table unload mechanism to unregister platform devices
created when the given table was loaded (Andy Shevchenko).
- Rework the lid blacklist handling in the button driver and add
more lid quirks to it (Hans de Goede).
- Improve ACPI-based device enumeration for some platforms based
on Intel BayTrail SoCs (Hans de Goede).
- Add an OpRegion driver for the Cherry Trail Crystal Cove PMIC
and prevent handlers from being registered for unhandled PMIC
OpRegions (Hans de Goede).
- Unify ACPI _HID/_UID matching (Andy Shevchenko).
- Clean up documentation and comments (Cao jin, James Pack, Kacper
Piwiński).
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Merge tag 'acpi-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI updates from Rafael Wysocki:
"These update the ACPICA code in the kernel to upstream revision
20191018, add support for EFI specific purpose memory, update the ACPI
EC driver to make it work on systems with hardware-reduced ACPI,
improve ACPI-based device enumeration for some platforms, rework the
lid blacklist handling in the button driver and add more lid quirks to
it, unify ACPI _HID/_UID matching, fix assorted issues and clean up
the code and documentation.
Specifics:
- Update the ACPICA code in the kernel to upstream revision 20191018
including:
* Fixes for Clang warnings (Bob Moore)
* Fix for possible overflow in get_tick_count() (Bob Moore)
* Introduction of acpi_unload_table() (Bob Moore)
* Debugger and utilities updates (Erik Schmauss)
* Fix for unloading tables loaded via configfs (Nikolaus Voss)
- Add support for EFI specific purpose memory to optionally allow
either application-exclusive or core-kernel-mm managed access to
differentiated memory (Dan Williams)
- Fix and clean up processing of the HMAT table (Brice Goglin, Qian
Cai, Tao Xu)
- Update the ACPI EC driver to make it work on systems with
hardware-reduced ACPI (Daniel Drake)
- Always build in support for the Generic Event Device (GED) to allow
one kernel binary to work both on systems with full hardware ACPI
and hardware-reduced ACPI (Arjan van de Ven)
- Fix the table unload mechanism to unregister platform devices
created when the given table was loaded (Andy Shevchenko)
- Rework the lid blacklist handling in the button driver and add more
lid quirks to it (Hans de Goede)
- Improve ACPI-based device enumeration for some platforms based on
Intel BayTrail SoCs (Hans de Goede)
- Add an OpRegion driver for the Cherry Trail Crystal Cove PMIC and
prevent handlers from being registered for unhandled PMIC OpRegions
(Hans de Goede)
- Unify ACPI _HID/_UID matching (Andy Shevchenko)
- Clean up documentation and comments (Cao jin, James Pack, Kacper
Piwiński)"
* tag 'acpi-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (52 commits)
ACPI: OSI: Shoot duplicate word
ACPI: HMAT: use %u instead of %d to print u32 values
ACPI: NUMA: HMAT: fix a section mismatch
ACPI: HMAT: don't mix pxm and nid when setting memory target processor_pxm
ACPI: NUMA: HMAT: Register "soft reserved" memory as an "hmem" device
ACPI: NUMA: HMAT: Register HMAT at device_initcall level
device-dax: Add a driver for "hmem" devices
dax: Fix alloc_dax_region() compile warning
lib: Uplevel the pmem "region" ida to a global allocator
x86/efi: Add efi_fake_mem support for EFI_MEMORY_SP
arm/efi: EFI soft reservation to memblock
x86/efi: EFI soft reservation to E820 enumeration
efi: Common enable/disable infrastructure for EFI soft reservation
x86/efi: Push EFI_MEMMAP check into leaf routines
efi: Enumerate EFI_MEMORY_SP
ACPI: NUMA: Establish a new drivers/acpi/numa/ directory
ACPICA: Update version to 20191018
ACPICA: debugger: remove leading whitespaces when converting a string to a buffer
ACPICA: acpiexec: initialize all simple types and field units from user input
ACPICA: debugger: add field unit support for acpi_db_get_next_token
...
This blacklists several compilation units from KCSAN. See the respective
inline comments for the reasoning.
Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
UEFI 2.8 defines an EFI_MEMORY_SP attribute bit to augment the
interpretation of the EFI Memory Types as "reserved for a specific
purpose".
The proposed Linux behavior for specific purpose memory is that it is
reserved for direct-access (device-dax) by default and not available for
any kernel usage, not even as an OOM fallback. Later, through udev
scripts or another init mechanism, these device-dax claimed ranges can
be reconfigured and hot-added to the available System-RAM with a unique
node identifier. This device-dax management scheme implements "soft" in
the "soft reserved" designation by allowing some or all of the
reservation to be recovered as typical memory. This policy can be
disabled at compile-time with CONFIG_EFI_SOFT_RESERVE=n, or runtime with
efi=nosoftreserve.
For this patch, update the ARM paths that consider
EFI_CONVENTIONAL_MEMORY to optionally take the EFI_MEMORY_SP attribute
into account as a reservation indicator. Publish the soft reservation as
IORES_DESC_SOFT_RESERVED memory, similar to x86.
(Based on an original patch by Ard)
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
UEFI 2.8 defines an EFI_MEMORY_SP attribute bit to augment the
interpretation of the EFI Memory Types as "reserved for a specific
purpose".
The proposed Linux behavior for specific purpose memory is that it is
reserved for direct-access (device-dax) by default and not available for
any kernel usage, not even as an OOM fallback. Later, through udev
scripts or another init mechanism, these device-dax claimed ranges can
be reconfigured and hot-added to the available System-RAM with a unique
node identifier. This device-dax management scheme implements "soft" in
the "soft reserved" designation by allowing some or all of the
reservation to be recovered as typical memory. This policy can be
disabled at compile-time with CONFIG_EFI_SOFT_RESERVE=n, or runtime with
efi=nosoftreserve.
As for this patch, define the common helpers to determine if the
EFI_MEMORY_SP attribute should be honored. The determination needs to be
made early to prevent the kernel from being loaded into soft-reserved
memory, or otherwise allowing early allocations to land there. Follow-on
changes are needed per architecture to leverage these helpers in their
respective mem-init paths.
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Wire up the existing code for ARM that loads the TPM event log into
OS accessible buffers while running the EFI stub so that the kernel
proper can access it at runtime.
Tested-by: Zou Cao <zoucao@linux.alibaba.com>
Signed-off-by: Xinwei Kong <kong.kongxinwei@hisilicon.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Invoke the EFI_RNG_PROTOCOL protocol in the context of the x86 EFI stub,
same as is done on arm/arm64 since commit 568bc4e870 ("efi/arm*/libstub:
Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table"). Within the stub,
a Linux-specific RNG seed UEFI config table will be seeded. The EFI routines
in the core kernel will pick that up later, yet still early during boot,
to seed the kernel entropy pool. If CONFIG_RANDOM_TRUST_BOOTLOADER, entropy
is credited for this seed.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
To handle all arch-specific peculiarities when calling an EFI protocol
function, a wrapper efi_call_proto() exists on all relevant architectures.
On arm/arm64, this is merely a plain function call. On x86, a special EFI
entry stub needs to be used, however, as the calling convention differs.
To make the efi/random stub arch-independent, use efi_call_proto()
instead of the existing non-portable calls to the EFI get_rng protocol
function. This also requires the addition of some typedefs.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Currently, kernel fails to boot on some HyperV VMs when using EFI.
And it's a potential issue on all x86 platforms.
It's caused by broken kernel relocation on EFI systems, when below three
conditions are met:
1. Kernel image is not loaded to the default address (LOAD_PHYSICAL_ADDR)
by the loader.
2. There isn't enough room to contain the kernel, starting from the
default load address (eg. something else occupied part the region).
3. In the memmap provided by EFI firmware, there is a memory region
starts below LOAD_PHYSICAL_ADDR, and suitable for containing the
kernel.
EFI stub will perform a kernel relocation when condition 1 is met. But
due to condition 2, EFI stub can't relocate kernel to the preferred
address, so it fallback to ask EFI firmware to alloc lowest usable memory
region, got the low region mentioned in condition 3, and relocated
kernel there.
It's incorrect to relocate the kernel below LOAD_PHYSICAL_ADDR. This
is the lowest acceptable kernel relocation address.
The first thing goes wrong is in arch/x86/boot/compressed/head_64.S.
Kernel decompression will force use LOAD_PHYSICAL_ADDR as the output
address if kernel is located below it. Then the relocation before
decompression, which move kernel to the end of the decompression buffer,
will overwrite other memory region, as there is no enough memory there.
To fix it, just don't let EFI stub relocate the kernel to any address
lower than lowest acceptable address.
[ ardb: introduce efi_low_alloc_above() to reduce the scope of the change ]
Signed-off-by: Kairui Song <kasong@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191029173755.27149-6-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The EFI stubloader for ARM starts out by allocating a 32 MB window
at the base of RAM, in order to ensure that the decompressor (which
blindly copies the uncompressed kernel into that window) does not
overwrite other allocations that are made while running in the context
of the EFI firmware.
In some cases, (e.g., U-Boot running on the Raspberry Pi 2), this is
causing boot failures because this initial allocation conflicts with
a page of reserved memory at the base of RAM that contains the SMP spin
tables and other pieces of firmware data and which was put there by
the bootloader under the assumption that the TEXT_OFFSET window right
below the kernel is only used partially during early boot, and will be
left alone once the memory reservations are processed and taken into
account.
So let's permit reserved memory regions to exist in the region starting
at the base of RAM, and ending at TEXT_OFFSET - 5 * PAGE_SIZE, which is
the window below the kernel that is not touched by the early boot code.
Tested-by: Guillaume Gardet <Guillaume.Gardet@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Chester Lin <clin@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191029173755.27149-5-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fix get_efi_config_table using the wrong structs when booting a
64 bit kernel on 32 bit firmware.
Fixes: 82d736ac56 ("Abstract out support for locating an EFI config table")
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-By: Matthew Garrett <mjg59@google.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
After the first call to GetEventLog() on UEFI systems using the TCG2
crypto agile log format, any further log events (other than those
triggered by ExitBootServices()) will be logged in both the main log and
also in the Final Events Log. While the kernel only calls GetEventLog()
immediately before ExitBootServices(), we can't control whether earlier
parts of the boot process have done so. This will result in log entries
that exist in both logs, and so the current approach of simply appending
the Final Event Log to the main log will result in events being
duplicated.
We can avoid this problem by looking at the size of the Final Event Log
just before we call ExitBootServices() and exporting this to the main
kernel. The kernel can then skip over all events that occured before
ExitBootServices() and only append events that were not also logged to
the main log.
Signed-off-by: Matthew Garrett <mjg59@google.com>
Reported-by: Joe Richey <joerichey@google.com>
Suggested-by: Joe Richey <joerichey@google.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
We want to grab a pointer to the TPM final events table, so abstract out
the existing code for finding an FDT table and make it generic.
Signed-off-by: Matthew Garrett <mjg59@google.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Right now we only attempt to obtain the SHA1-only event log. The
protocol also supports a crypto agile log format, which contains digests
for all algorithms in use. Attempt to obtain this first, and fall back
to obtaining the older format if the system doesn't support it. This is
lightly complicated by the event sizes being variable (as we don't know
in advance which algorithms are in use), and the interface giving us
back a pointer to the start of the final entry rather than a pointer to
the end of the log - as a result, we need to parse the final entry to
figure out its length in order to know how much data to copy up to the
OS.
Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Bartosz Szczepanek <bsz@semihalf.com>
Tested-by: Bartosz Szczepanek <bsz@semihalf.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Based on 1 normalized pattern(s):
this file is part of the linux kernel and is made available under
the terms of the gnu general public license version 2
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 28 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.534229504@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Mostly just incremental improvements here:
- Introduce AT_HWCAP2 for advertising CPU features to userspace
- Expose SVE2 availability to userspace
- Support for "data cache clean to point of deep persistence" (DC PODP)
- Honour "mitigations=off" on the cmdline and advertise status via sysfs
- CPU timer erratum workaround (Neoverse-N1 #1188873)
- Introduce perf PMU driver for the SMMUv3 performance counters
- Add config option to disable the kuser helpers page for AArch32 tasks
- Futex modifications to ensure liveness under contention
- Rework debug exception handling to seperate kernel and user handlers
- Non-critical fixes and cleanup
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
"Mostly just incremental improvements here:
- Introduce AT_HWCAP2 for advertising CPU features to userspace
- Expose SVE2 availability to userspace
- Support for "data cache clean to point of deep persistence" (DC PODP)
- Honour "mitigations=off" on the cmdline and advertise status via
sysfs
- CPU timer erratum workaround (Neoverse-N1 #1188873)
- Introduce perf PMU driver for the SMMUv3 performance counters
- Add config option to disable the kuser helpers page for AArch32 tasks
- Futex modifications to ensure liveness under contention
- Rework debug exception handling to seperate kernel and user
handlers
- Non-critical fixes and cleanup"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (92 commits)
Documentation: Add ARM64 to kernel-parameters.rst
arm64/speculation: Support 'mitigations=' cmdline option
arm64: ssbs: Don't treat CPUs with SSBS as unaffected by SSB
arm64: enable generic CPU vulnerabilites support
arm64: add sysfs vulnerability show for speculative store bypass
arm64: Fix size of __early_cpu_boot_status
clocksource/arm_arch_timer: Use arch_timer_read_counter to access stable counters
clocksource/arm_arch_timer: Remove use of workaround static key
clocksource/arm_arch_timer: Drop use of static key in arch_timer_reg_read_stable
clocksource/arm_arch_timer: Direcly assign set_next_event workaround
arm64: Use arch_timer_read_counter instead of arch_counter_get_cntvct
watchdog/sbsa: Use arch_timer_read_counter instead of arch_counter_get_cntvct
ARM: vdso: Remove dependency with the arch_timer driver internals
arm64: Apply ARM64_ERRATUM_1188873 to Neoverse-N1
arm64: Add part number for Neoverse N1
arm64: Make ARM64_ERRATUM_1188873 depend on COMPAT
arm64: Restrict ARM64_ERRATUM_1188873 mitigation to AArch32
arm64: mm: Remove pte_unmap_nested()
arm64: Fix compiler warning from pte_unmap() with -Wunused-but-set-variable
arm64: compat: Reduce address limit for 64K pages
...
In preparation for arm64 supporting ftrace built on other compiler
options, let's have Makefiles remove the $(CC_FLAGS_FTRACE) flags,
whatever these maybe, rather than assuming '-pg'.
While at it, fix arm32 as well. There should be no functional change as
a result of this patch.
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Commit f922c4abdf ("module: allow symbol exports to be disabled")
introduced a way to inhibit generation of kcrctab/ksymtab sections
when building ordinary kernel code to be used in a different execution
context (decompressor, EFI stub, etc)
That means we no longer have to strip those sections explicitly when
building the EFI libstub objects, so drop this from the Makefile.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20190328193429.21373-6-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
It took me a while to understand what is going on in the nested
if-blocks.
Simplify it by removing unneeded code.
- if_changed automatically adds 'set -e', so any failure in the
series of commands makes it immediately fail as a whole.
So, the outer if block is entirely redundant.
- Since commit 9c2af1c737 ("kbuild: add .DELETE_ON_ERROR special target"),
GNU Make automatically deletes the target on any failure
in its recipe. The explicit 'rm -f $@' is redundant.
- Surrounding commands with ( ) will spawn a subshell to execute them
in it, but it is rarely useful to do so.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20190328193429.21373-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
