In the EFI config table, rename LINUX_EFI_SCREEN_INFO_TABLE_GUID to
LINUX_EFI_PRIMARY_DISPLAY_TABLE_GUID. Read sysfb_primary_display from
the entry. In addition to the screen_info, the entry now also contains
EDID information.
In libstub, replace struct screen_info with struct sysfb_display_info
from the kernel's sysfb_primary_display and rename functions
accordingly. Transfer it to the runtime kernel using the kernel's
global state or the LINUX_EFI_PRIMARY_DISPLAY_TABLE_GUID config-table
entry.
With CONFIG_FIRMWARE_EDID=y, libstub now transfers the GOP device's EDID
information to the kernel. If CONFIG_FIRMWARE_EDID=n, EDID information
is disabled. Make the Kconfig symbol CONFIG_FIRMWARE_EDID available with
EFI. Setting the value to 'n' disables EDID support.
Also rename screen_info.c to primary_display.c and adapt the contained
comment according to the changes.
Link: https://lore.kernel.org/all/20251126160854.553077-8-tzimmermann@suse.de/
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
[ardb: depend on EFI_GENERIC_STUB not EFI, fix conflicts after dropping
the preceding patch from the series]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Pull EFI updates from Ard Biesheuvel:
"The usual trickle of EFI contributions:
- Parse SMBIOS tables in memory directly on Macbooks that do not
implement the EFI SMBIOS protocol
- Obtain EDID information from the primary display while running in
the EFI stub, and expose it via bootparams on x86 (generic method
is in the works, and will likely land during the next cycle)
- Bring CPER handling for ARM systems up to data with the latest EFI
spec changes
- Various cosmetic changes"
* tag 'efi-next-for-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
docs: efi: add CPER functions to driver-api
efi/cper: align ARM CPER type with UEFI 2.9A/2.10 specs
efi/cper: Add a new helper function to print bitmasks
efi/cper: Adjust infopfx size to accept an extra space
RAS: Report all ARM processor CPER information to userspace
efi/libstub: x86: Store EDID in boot_params
efi/libstub: gop: Add support for reading EDID
efi/libstub: gop: Initialize screen_info in helper function
efi/libstub: gop: Find GOP handle instead of GOP data
efi: Fix trailing whitespace in header file
efi/memattr: Convert efi_memattr_init() return type to void
efi: stmm: fix kernel-doc "bad line" warnings
efi/riscv: Remove the useless failure return message print
efistub/x86: Add fallback for SMBIOS record lookup
Add support for EFI_EDID_DISCOVERED_PROTOCOL and EFI_EDID_ACTIVE_PROTOCOL
as defined in UEFI 2.8, sec 12.9. Define GUIDs and data structures in the
rsp header files.
In the GOP setup function, read the EDID of the primary GOP device. First
try EFI_EDID_ACTIVE_PROTOCOL, which supports user-specified EDID data. Or
else try EFI_EDID_DISCOVERED_PROTOCOL, which returns the display device's
native EDID. If no EDID could be retrieved, clear the storage.
Rename efi_setup_gop() to efi_setup_graphics() to reflect the changes
Let callers pass an optional instance of struct edid_data, if they are
interested.
While screen_info and edid_info come from the same device handle, they
should be considered indendent data. The former refers to the graphics
mode, the latter refers to the display device. GOP devices might not
provide both.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
The EFI runtime wrappers use a file local semaphore to serialize access
to the EFI runtime services. This means that any calls to the arch
wrappers around the runtime services will also be serialized, removing
the need for redundant locking.
For robustness, add a facility that allows those arch wrappers to assert
that the semaphore was taken by the current task.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The efi_memattr_init() function's return values (0 and -ENOMEM) are never
checked by callers. Convert the function to return void since the return
status is unused.
Signed-off-by: Breno Leitao <leitao@debian.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Pull EFI updates from Ard Biesheuvel:
- Expose the OVMF firmware debug log via sysfs
- Lower the default log level for the EFI stub to avoid corrupting any
splash screens with unimportant diagnostic output
* tag 'efi-next-for-v6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
efi: add API doc entry for ovmf_debug_log
efistub: Lower default log level
efi: add ovmf debug log driver
GCC appears to have kind of fragile inlining heuristics, in the
sense that it can change whether or not it inlines something based on
optimizations. It looks like the kcov instrumentation being added (or in
this case, removed) from a function changes the optimization results,
and some functions marked "inline" are _not_ inlined. In that case,
we end up with __init code calling a function not marked __init, and we
get the build warnings I'm trying to eliminate in the coming patch that
adds __no_sanitize_coverage to __init functions:
WARNING: modpost: vmlinux: section mismatch in reference: xbc_exit+0x8 (section: .text.unlikely) -> _xbc_exit (section: .init.text)
WARNING: modpost: vmlinux: section mismatch in reference: real_mode_size_needed+0x15 (section: .text.unlikely) -> real_mode_blob_end (section: .init.data)
WARNING: modpost: vmlinux: section mismatch in reference: __set_percpu_decrypted+0x16 (section: .text.unlikely) -> early_set_memory_decrypted (section: .init.text)
WARNING: modpost: vmlinux: section mismatch in reference: memblock_alloc_from+0x26 (section: .text.unlikely) -> memblock_alloc_try_nid (section: .init.text)
WARNING: modpost: vmlinux: section mismatch in reference: acpi_arch_set_root_pointer+0xc (section: .text.unlikely) -> x86_init (section: .init.data)
WARNING: modpost: vmlinux: section mismatch in reference: acpi_arch_get_root_pointer+0x8 (section: .text.unlikely) -> x86_init (section: .init.data)
WARNING: modpost: vmlinux: section mismatch in reference: efi_config_table_is_usable+0x16 (section: .text.unlikely) -> xen_efi_config_table_is_usable (section: .init.text)
This problem is somewhat fragile (though using either __always_inline
or __init will deterministically solve it), but we've tripped over
this before with GCC and the solution has usually been to just use
__always_inline and move on.
For x86 this means forcing several functions to be inline with
__always_inline.
Link: https://lore.kernel.org/r/20250724055029.3623499-2-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
Recent OVMF versions (edk2-stable202508 + newer) can write their debug
log to a memory buffer. This driver exposes the log content via sysfs
(/sys/firmware/efi/ovmf_debug_log).
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
UEFI 2.11 introduced EFI_MEMORY_HOT_PLUGGABLE to annotate system memory
regions that are 'cold plugged' at boot, i.e., hot pluggable memory that
is available from early boot, and described as system RAM by the
firmware.
Existing loaders and EFI applications running in the boot context will
happily use this memory for allocating data structures that cannot be
freed or moved at runtime, and this prevents the memory from being
unplugged. Going forward, the new EFI_MEMORY_HOT_PLUGGABLE attribute
should be tested, and memory annotated as such should be avoided for
such allocations.
In the EFI stub, there are a couple of occurrences where, instead of the
high-level AllocatePages() UEFI boot service, a low-level code sequence
is used that traverses the EFI memory map and carves out the requested
number of pages from a free region. This is needed, e.g., for allocating
as low as possible, or for allocating pages at random.
While AllocatePages() should presumably avoid special purpose memory and
cold plugged regions, this manual approach needs to incorporate this
logic itself, in order to prevent the kernel itself from ending up in a
hot unpluggable region, preventing it from being unplugged.
So add the EFI_MEMORY_HOTPLUGGABLE macro definition, and check for it
where appropriate.
Cc: stable@vger.kernel.org
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
UGA is the EFI graphical output protocol that preceded GOP, and has been
long obsolete. Drop support for it from the x86 implementation of the
EFI stub - other architectures never bothered to implement it (save for
ia64)
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Drop support for the EFI_PROPERTIES_TABLE. It was a failed, short-lived
experiment that broke the boot both on Linux and Windows, and was
replaced by the EFI_MEMORY_ATTRIBUTES_TABLE shortly after.
Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Nicolas Saenz Julienne <nsaenz@amazon.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Since commit cf8e865810 ("arch: Remove Itanium (IA-64) architecture"),
this is not used anymore.
Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
While efi_memory_attributes_table_t::entry isn't used directly as an
array, it is used as a base for pointer arithmetic. The type is wrong
as it's not technically an array of efi_memory_desc_t's; they could be
larger. Regardless, leave the type unchanged and remove the old style
"0" array size. Additionally replace the open-coded entry offset code
with the existing efi_memdesc_ptr() helper.
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
0c18184de9 ("platform/x86: apple-gmux: support MMIO gmux on T2 Macs")
brought support for T2 Macs in apple-gmux. But in order to use dual GPU,
the integrated GPU has to be enabled. On such dual GPU EFI Macs, the EFI
stub needs to report that it is booting macOS in order to prevent the
firmware from disabling the iGPU.
This patch is also applicable for some non T2 Intel Macs.
Based on this patch for GRUB by Andreas Heider <andreas@heider.io>:
https://lists.gnu.org/archive/html/grub-devel/2013-12/msg00442.html
Credits also goto Kerem Karabay <kekrby@gmail.com> for helping porting
the patch to the Linux kernel.
Cc: Orlando Chamberlain <orlandoch.dev@gmail.com>
Signed-off-by: Aditya Garg <gargaditya08@live.com>
[ardb: limit scope using list of DMI matches provided by Lukas and Orlando]
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Tested-by: Aditya Garg <gargaditya08@live.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
The smbios.c source file is not currently included in the x86 build, and
before we can do so, it needs some tweaks to build correctly in
combination with the EFI mixed mode support.
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
The UEFI specification does not make any mention of a maximum variable
name size, so the headers and implementation shouldn't claim that one
exists either.
Comments referring to this limit have been removed or rewritten, as this
is an implementation detail local to the Linux kernel.
Where appropriate, the magic value of 1024 has been replaced with
EFI_VAR_NAME_LEN, as this is used for the efi_variable struct
definition. This in itself does not change any behavior, but should
serve as points of interest when making future changes in the same area.
A related build-time check has been added to ensure that the special
512 byte sized buffer will not overflow with a potentially decreased
EFI_VAR_NAME_LEN.
Signed-off-by: Tim Schumacher <timschumi@gmx.de>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Pull MM updates from Andrew Morton:
- Sumanth Korikkar has taught s390 to allocate hotplug-time page frames
from hotplugged memory rather than only from main memory. Series
"implement "memmap on memory" feature on s390".
- More folio conversions from Matthew Wilcox in the series
"Convert memcontrol charge moving to use folios"
"mm: convert mm counter to take a folio"
- Chengming Zhou has optimized zswap's rbtree locking, providing
significant reductions in system time and modest but measurable
reductions in overall runtimes. The series is "mm/zswap: optimize the
scalability of zswap rb-tree".
- Chengming Zhou has also provided the series "mm/zswap: optimize zswap
lru list" which provides measurable runtime benefits in some
swap-intensive situations.
- And Chengming Zhou further optimizes zswap in the series "mm/zswap:
optimize for dynamic zswap_pools". Measured improvements are modest.
- zswap cleanups and simplifications from Yosry Ahmed in the series
"mm: zswap: simplify zswap_swapoff()".
- In the series "Add DAX ABI for memmap_on_memory", Vishal Verma has
contributed several DAX cleanups as well as adding a sysfs tunable to
control the memmap_on_memory setting when the dax device is
hotplugged as system memory.
- Johannes Weiner has added the large series "mm: zswap: cleanups",
which does that.
- More DAMON work from SeongJae Park in the series
"mm/damon: make DAMON debugfs interface deprecation unignorable"
"selftests/damon: add more tests for core functionalities and corner cases"
"Docs/mm/damon: misc readability improvements"
"mm/damon: let DAMOS feeds and tame/auto-tune itself"
- In the series "mm/mempolicy: weighted interleave mempolicy and sysfs
extension" Rakie Kim has developed a new mempolicy interleaving
policy wherein we allocate memory across nodes in a weighted fashion
rather than uniformly. This is beneficial in heterogeneous memory
environments appearing with CXL.
- Christophe Leroy has contributed some cleanup and consolidation work
against the ARM pagetable dumping code in the series "mm: ptdump:
Refactor CONFIG_DEBUG_WX and check_wx_pages debugfs attribute".
- Luis Chamberlain has added some additional xarray selftesting in the
series "test_xarray: advanced API multi-index tests".
- Muhammad Usama Anjum has reworked the selftest code to make its
human-readable output conform to the TAP ("Test Anything Protocol")
format. Amongst other things, this opens up the use of third-party
tools to parse and process out selftesting results.
- Ryan Roberts has added fork()-time PTE batching of THP ptes in the
series "mm/memory: optimize fork() with PTE-mapped THP". Mainly
targeted at arm64, this significantly speeds up fork() when the
process has a large number of pte-mapped folios.
- David Hildenbrand also gets in on the THP pte batching game in his
series "mm/memory: optimize unmap/zap with PTE-mapped THP". It
implements batching during munmap() and other pte teardown
situations. The microbenchmark improvements are nice.
- And in the series "Transparent Contiguous PTEs for User Mappings"
Ryan Roberts further utilizes arm's pte's contiguous bit ("contpte
mappings"). Kernel build times on arm64 improved nicely. Ryan's
series "Address some contpte nits" provides some followup work.
- In the series "mm/hugetlb: Restore the reservation" Breno Leitao has
fixed an obscure hugetlb race which was causing unnecessary page
faults. He has also added a reproducer under the selftest code.
- In the series "selftests/mm: Output cleanups for the compaction
test", Mark Brown did what the title claims.
- Kinsey Ho has added the series "mm/mglru: code cleanup and
refactoring".
- Even more zswap material from Nhat Pham. The series "fix and extend
zswap kselftests" does as claimed.
- In the series "Introduce cpu_dcache_is_aliasing() to fix DAX
regression" Mathieu Desnoyers has cleaned up and fixed rather a mess
in our handling of DAX on archiecctures which have virtually aliasing
data caches. The arm architecture is the main beneficiary.
- Lokesh Gidra's series "per-vma locks in userfaultfd" provides
dramatic improvements in worst-case mmap_lock hold times during
certain userfaultfd operations.
- Some page_owner enhancements and maintenance work from Oscar Salvador
in his series
"page_owner: print stacks and their outstanding allocations"
"page_owner: Fixup and cleanup"
- Uladzislau Rezki has contributed some vmalloc scalability
improvements in his series "Mitigate a vmap lock contention". It
realizes a 12x improvement for a certain microbenchmark.
- Some kexec/crash cleanup work from Baoquan He in the series "Split
crash out from kexec and clean up related config items".
- Some zsmalloc maintenance work from Chengming Zhou in the series
"mm/zsmalloc: fix and optimize objects/page migration"
"mm/zsmalloc: some cleanup for get/set_zspage_mapping()"
- Zi Yan has taught the MM to perform compaction on folios larger than
order=0. This a step along the path to implementaton of the merging
of large anonymous folios. The series is named "Enable >0 order folio
memory compaction".
- Christoph Hellwig has done quite a lot of cleanup work in the
pagecache writeback code in his series "convert write_cache_pages()
to an iterator".
- Some modest hugetlb cleanups and speedups in Vishal Moola's series
"Handle hugetlb faults under the VMA lock".
- Zi Yan has changed the page splitting code so we can split huge pages
into sizes other than order-0 to better utilize large folios. The
series is named "Split a folio to any lower order folios".
- David Hildenbrand has contributed the series "mm: remove
total_mapcount()", a cleanup.
- Matthew Wilcox has sought to improve the performance of bulk memory
freeing in his series "Rearrange batched folio freeing".
- Gang Li's series "hugetlb: parallelize hugetlb page init on boot"
provides large improvements in bootup times on large machines which
are configured to use large numbers of hugetlb pages.
- Matthew Wilcox's series "PageFlags cleanups" does that.
- Qi Zheng's series "minor fixes and supplement for ptdesc" does that
also. S390 is affected.
- Cleanups to our pagemap utility functions from Peter Xu in his series
"mm/treewide: Replace pXd_large() with pXd_leaf()".
- Nico Pache has fixed a few things with our hugepage selftests in his
series "selftests/mm: Improve Hugepage Test Handling in MM
Selftests".
- Also, of course, many singleton patches to many things. Please see
the individual changelogs for details.
* tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (435 commits)
mm/zswap: remove the memcpy if acomp is not sleepable
crypto: introduce: acomp_is_async to expose if comp drivers might sleep
memtest: use {READ,WRITE}_ONCE in memory scanning
mm: prohibit the last subpage from reusing the entire large folio
mm: recover pud_leaf() definitions in nopmd case
selftests/mm: skip the hugetlb-madvise tests on unmet hugepage requirements
selftests/mm: skip uffd hugetlb tests with insufficient hugepages
selftests/mm: dont fail testsuite due to a lack of hugepages
mm/huge_memory: skip invalid debugfs new_order input for folio split
mm/huge_memory: check new folio order when split a folio
mm, vmscan: retry kswapd's priority loop with cache_trim_mode off on failure
mm: add an explicit smp_wmb() to UFFDIO_CONTINUE
mm: fix list corruption in put_pages_list
mm: remove folio from deferred split list before uncharging it
filemap: avoid unnecessary major faults in filemap_fault()
mm,page_owner: drop unnecessary check
mm,page_owner: check for null stack_record before bumping its refcount
mm: swap: fix race between free_swap_and_cache() and swapoff()
mm/treewide: align up pXd_leaf() retval across archs
mm/treewide: drop pXd_large()
...
If the virtual firmware implements TPM support, TCG2 protocol will be
used for kernel measurements and event logging support. But in CC
environment, not all platforms support or enable the TPM feature. UEFI
specification [1] exposes protocol and interfaces used for kernel
measurements in CC platforms without TPM support.
More details about the EFI CC measurements and logging can be found
in [1].
Link: https://uefi.org/specs/UEFI/2.10/38_Confidential_Computing.html#efi-cc-measurement-protocol [1]
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
[ardb: Drop code changes, keep typedefs and #define's only]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
The LINUX_EFI_ GUID identifiers are only intended to be used to refer to
GUIDs that are part of the Linux implementation, and are not considered
external ABI. (Famous last words).
GUIDs that already have a symbolic name in the spec should use that
name, to avoid confusion between firmware components. So use the
official name EFI_TCG2_FINAL_EVENTS_TABLE_GUID for the TCG2 'final
events' configuration table.
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
