kernel/linux.git/drivers/firmware/efi, branch v6.13.6

efi: Don't map the entire mokvar table to determine its size

2025-03-07T17:27:15+00:00

commit 2b90e7ace79774a3540ce569e000388f8d22c9e0 upstream. Currently, when validating the mokvar table, we (re)map the entire table on each iteration of the loop, adding space as we discover new entries. If the table grows over a certain size, this fails due to limitations of early_memmap(), and we get a failure and traceback: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at mm/early_ioremap.c:139 __early_ioremap+0xef/0x220 ... Call Trace: ? __early_ioremap+0xef/0x220 ? __warn.cold+0x93/0xfa ? __early_ioremap+0xef/0x220 ? report_bug+0xff/0x140 ? early_fixup_exception+0x5d/0xb0 ? early_idt_handler_common+0x2f/0x3a ? __early_ioremap+0xef/0x220 ? efi_mokvar_table_init+0xce/0x1d0 ? setup_arch+0x864/0xc10 ? start_kernel+0x6b/0xa10 ? x86_64_start_reservations+0x24/0x30 ? x86_64_start_kernel+0xed/0xf0 ? common_startup_64+0x13e/0x141 ---[ end trace 0000000000000000 ]--- mokvar: Failed to map EFI MOKvar config table pa=0x7c4c3000, size=265187. Mapping the entire structure isn't actually necessary, as we don't ever need more than one entry header mapped at once. Changes efi_mokvar_table_init() to only map each entry header, not the entire table, when determining the table size. Since we're not mapping any data past the variable name, it also changes the code to enforce that each variable name is NUL terminated, rather than attempting to verify it in place. Cc: Signed-off-by: Peter Jones Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman

efi: Avoid cold plugged memory for placing the kernel

2025-02-21T13:11:05+00:00

commit ba69e0750b0362870294adab09339a0c39c3beaf upstream. 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 Signed-off-by: Greg Kroah-Hartman

efi: libstub: Use '-std=gnu11' to fix build with GCC 15

2025-02-17T10:36:24+00:00

commit 8ba14d9f490aef9fd535c04e9e62e1169eb7a055 upstream. GCC 15 changed the default C standard version to C23, which should not have impacted the kernel because it requests the gnu11 standard via '-std=' in the main Makefile. However, the EFI libstub Makefile uses its own set of KBUILD_CFLAGS for x86 without a '-std=' value (i.e., using the default), resulting in errors from the kernel's definitions of bool, true, and false in stddef.h, which are reserved keywords under C23. ./include/linux/stddef.h:11:9: error: expected identifier before ‘false’ 11 | false = 0, ./include/linux/types.h:35:33: error: two or more data types in declaration specifiers 35 | typedef _Bool bool; Set '-std=gnu11' in the x86 cflags to resolve the error and consistently use the same C standard version for the entire kernel. All other architectures reuse KBUILD_CFLAGS from the rest of the kernel, so this issue is not visible for them. Cc: stable@vger.kernel.org Reported-by: Kostadin Shishmanov Closes: https://lore.kernel.org/4OAhbllK7x4QJGpZjkYjtBYNLd_2whHx9oFiuZcGwtVR4hIzvduultkgfAIRZI3vQpZylu7Gl929HaYFRGeMEalWCpeMzCIIhLxxRhq4U-Y=@protonmail.com/ Reported-by: Jakub Jelinek Closes: https://lore.kernel.org/Z4467umXR2PZ0M1H@tucnak/ Signed-off-by: Nathan Chancellor Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman

efi: sysfb_efi: fix W=1 warnings when EFI is not set

2025-02-08T09:01:58+00:00

[ Upstream commit 19fdc68aa7b90b1d3d600e873a3e050a39e7663d ] A build with W=1 fails because there are code and data that are not needed or used when CONFIG_EFI is not set. Move the "#ifdef CONFIG_EFI" block to earlier in the source file so that the unused code/data are not built. drivers/firmware/efi/sysfb_efi.c:345:39: warning: ‘efifb_fwnode_ops’ defined but not used [-Wunused-const-variable=] 345 | static const struct fwnode_operations efifb_fwnode_ops = { | ^~~~~~~~~~~~~~~~ drivers/firmware/efi/sysfb_efi.c:238:35: warning: ‘efifb_dmi_swap_width_height’ defined but not used [-Wunused-const-variable=] 238 | static const struct dmi_system_id efifb_dmi_swap_width_height[] __initconst = { | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/firmware/efi/sysfb_efi.c:188:35: warning: ‘efifb_dmi_system_table’ defined but not used [-Wunused-const-variable=] 188 | static const struct dmi_system_id efifb_dmi_system_table[] __initconst = { | ^~~~~~~~~~~~~~~~~~~~~~ Fixes: 15d27b15de96 ("efi: sysfb_efi: fix build when EFI is not set") Signed-off-by: Randy Dunlap Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202501071933.20nlmJJt-lkp@intel.com/ Cc: David Rheinsberg Cc: Hans de Goede Cc: Javier Martinez Canillas Cc: Peter Jones Cc: Simona Vetter Cc: linux-fbdev@vger.kernel.org Cc: Ard Biesheuvel Cc: linux-efi@vger.kernel.org Reviewed-by: Thomas Zimmermann Reviewed-by: Javier Martinez Canillas Signed-off-by: Ard Biesheuvel Signed-off-by: Sasha Levin

Merge tag 'efi-fixes-for-v6.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi

2024-12-15T23:33:41+00:00

Pull EFI fixes from Ard Biesheuvel: - Limit EFI zboot to GZIP and ZSTD before it comes in wider use - Fix inconsistent error when looking up a non-existent file in efivarfs with a name that does not adhere to the NAME-GUID format - Drop some unused code * tag 'efi-fixes-for-v6.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: efi/esrt: remove esre_attribute::store() efivarfs: Fix error on non-existent file efi/zboot: Limit compression options to GZIP and ZSTD

efi/esrt: remove esre_attribute::store()

2024-12-13T07:43:58+00:00

esre_attribute::store() is not needed since commit af97a77bc01c (efi: Move some sysfs files to be read-only by root). Drop it. Found by https://github.com/jirislaby/clang-struct. Signed-off-by: Jiri Slaby (SUSE) Cc: Ard Biesheuvel Cc: linux-efi@vger.kernel.org Signed-off-by: Ard Biesheuvel

efi/zboot: Limit compression options to GZIP and ZSTD

2024-12-06T15:59:56+00:00

For historical reasons, the legacy decompressor code on various architectures supports 7 different compression types for the compressed kernel image. EFI zboot is not a compression library museum, and so the options can be limited to what is likely to be useful in practice: - GZIP is tried and tested, and is still one of the fastest at decompression time, although the compression ratio is not very high; moreover, Fedora is already shipping EFI zboot kernels for arm64 that use GZIP, and QEMU implements direct support for it when booting a kernel without firmware loaded; - ZSTD has a very high compression ratio (although not the highest), and is almost as fast as GZIP at decompression time. Reducing the number of options makes it less of a hassle for other consumers of the EFI zboot format (such as QEMU today, and kexec in the future) to support it transparently without having to carry 7 different decompression libraries. Acked-by: Gerd Hoffmann Signed-off-by: Ard Biesheuvel

module: Convert symbol namespace to string literal

2024-12-02T19:34:44+00:00

Clean up the existing export namespace code along the same lines of commit 33def8498fdd ("treewide: Convert macro and uses of __section(foo) to __section("foo")") and for the same reason, it is not desired for the namespace argument to be a macro expansion itself. Scripted using git grep -l -e MODULE_IMPORT_NS -e EXPORT_SYMBOL_NS | while read file; do awk -i inplace ' /^#define EXPORT_SYMBOL_NS/ { gsub(/__stringify$ns$/, "ns"); print; next; } /^#define MODULE_IMPORT_NS/ { gsub(/__stringify$ns$/, "ns"); print; next; } /MODULE_IMPORT_NS/ { $0 = gensub(/MODULE_IMPORT_NS$([^)]*)$/, "MODULE_IMPORT_NS(\"\\1\")", "g"); } /EXPORT_SYMBOL_NS/ { if ($0 ~ /(EXPORT_SYMBOL_NS[^(]*)$([^,]+),/) { if ($0 !~ /(EXPORT_SYMBOL_NS[^(]*)\(([^,]+), ([^)]+)$/ && $0 !~ /(EXPORT_SYMBOL_NS[^(]*)/ && $0 !~ /^my/) { getline line; gsub(/[[:space:]]*\\$/, ""); gsub(/[[:space:]]/, "", line); $0 = $0 " " line; } $0 = gensub(/(EXPORT_SYMBOL_NS[^(]*)$([^,]+), ([^)]+)$/, "\\1(\\2, \"\\3\")", "g"); } } { print }' $file; done Requested-by: Masahiro Yamada Signed-off-by: Peter Zijlstra (Intel) Link: https://mail.google.com/mail/u/2/#inbox/FMfcgzQXKWgMmjdFwwdsfgxzKpVHWPlc Acked-by: Greg KH Signed-off-by: Linus Torvalds

efi: Fix memory leak in efivar_ssdt_load

2024-11-17T07:54:02+00:00

When we load SSDT from efi variable (specified with efivar_ssdt=boot command line argument) a name for the variable is allocated dynamically because we traverse all EFI variables. Unlike ACPI table data, which is later used by ACPI engine, the name is no longer needed once traverse is complete -- don't forget to free this memory. Same time we silently ignore any errors happened here let's print a message if something went wrong (but do not exit since this is not a critical error and the system should continue to boot). Also while here -- add a note why we keep SSDT table on success. Signed-off-by: Cyrill Gorcunov Signed-off-by: Ard Biesheuvel

efi/libstub: Take command line overrides into account for loaded files

2024-11-17T07:54:01+00:00

When CONFIG_CMDLINE_OVERRIDE or CONFIG_CMDLINE_FORCE are configured, the command line provided by the boot stack should be ignored, and only the built-in command line should be taken into account. Add the required handling of this when dealing with initrd= or dtb= command line options in the EFI stub. Signed-off-by: Ard Biesheuvel