kernel/git/stable/linux.git/arch/x86/boot, branch master

Merge tag 'liveupdate-v7.3-rc1-20260823' of git://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linux

2026-08-23T16:17:38+00:00

Pull more liveupdate updates from Mike Rapoport: "Make boot time huge page allocation work nicely with kexec handover. Today allocation of gigantic pages in HugeTLB cannot work reliably with kexec handover (KHO): - HugeTLB allocates gigantic pages using memblock and autoscaling of KHO scratch accounts for these allocations. When gigantic pages occupy half of the memory of more, KHO fails to allocate its scratch memory. - After kexec handover, memblock allocations exclusively use KHO scratch that is not supposed to contain preserved memory. This essentially blocks preservation of HugeTLB with gigantic pages. Extend early memory pools available for KHO kernel with areas that are guaranteed not to contain preserved memory" * tag 'liveupdate-v7.3-rc1-20260823' of git://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linux: (21 commits) kho: exclude hugetlb memory from scratch size calculation memblock: add memblock_reserved_hugetlb_size() memblock: make HugeTLB bootmem allocation work with KHO memblock: always include KHO headers kho: extend scratch mm/mm_init: don't rely on memblock to get KHO scratch migratetype kho: initialize preserved memory map radix tree earlier kho: initialize kho_scratch pointer earlier in boot kho: expose kho_scratch_overlap() to kexec_handover.h kho: add kho_radix_init_tree() kho: allow destroying KHO radix tree kho: allow early-boot usage of the KHO radix tree kho: add data argument to radix walk callback kho: add callback for table pages kho: add a struct for radix callbacks kho: move all memory retrieval logic to kho_mem_retrieve() kho: store incoming radix tree in kho_in kho: disallow wide keys in radix tree kho: make radix max key width more obvious kho: generalize radix tree APIs ...

Merge tag 'x86_cleanups_for_v7.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2026-08-19T01:34:58+00:00

Pull x86 cleanups from Borislav Petkov: - The usual pile of smallish cleanups and fixlets all over the place * tag 'x86_cleanups_for_v7.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu: Remove unnecessary __maybe_unused annotations x86/msr: Document the I/O-like write semantics in the msr driver x86/apic: Ensure ICR register write value is handled as 32 bits x86/boot/compressed/head_64.S: Clean up SEV-related comments Documentation/arch/x86/amd-memory-encryption.rst: Fix typo x86/platform/quark: Fix kernel-doc warnings in imr.c x86/ras: Move contents from arch/x86/ras/Kconfig into drivers/ras/Kconfig x86/cpu: Move intel_get_platform_id() to cpu/intel.c x86/mm: Fix typo in comment x86/fpu: Fix kernel-doc formatting above fpu_enable_guest_xfd_features() x86/cfi: Use symmetric SYM_START and SYM_END in __CFI_TYPE() x86/cfi: Add __init_or_module annotations for fineibt

Merge tag 'x86-boot-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2026-08-18T21:04:48+00:00

Pull x86 boot updates from Ingo Molnar: - Misc simplifications and cleanups (Thorsten Blum) * tag 'x86-boot-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot: Use bool and IS_ENABLED() to simplify query_edd() x86/boot: Use IS_ENABLED() to simplify built-in-or-module checks x86/purgatory: Return bool from verify_sha256_digest()

x86/boot: Use bool and IS_ENABLED() to simplify query_edd()

2026-08-04T17:45:55+00:00

In query_edd(), use bool for do_edd and initialize it directly from CONFIG_EDD_OFF via IS_ENABLED(). Also use bool for do_mbr and be_quiet. No change in functionality intended. Signed-off-by: Thorsten Blum Signed-off-by: Ingo Molnar Link: https://patch.msgid.link/20260804115227.62158-5-thorsten.blum@linux.dev

x86/boot: Use IS_ENABLED() to simplify built-in-or-module checks

2026-08-04T17:45:55+00:00

Replace open-coded built-in-or-module checks for CONFIG_APM, CONFIG_EDD, and CONFIG_X86_SPEEDSTEP_SMI with IS_ENABLED(). No change in functionality intended. Signed-off-by: Thorsten Blum Signed-off-by: Ingo Molnar Link: https://patch.msgid.link/20260804115227.62158-4-thorsten.blum@linux.dev

Merge branch 'mm-stable-6d098029de09' of https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm into kho-scratch

2026-07-30T07:53:28+00:00

x86/boot: Add volatile, clobbers and zero-length test in memcmp()

2026-07-28T23:32:44+00:00

Add the volatile qualifier and clobbers parameter to prevent bugs with instruction reordering and optimization. Also add TEST for the zero-length case to set ZF, as, if the count register is zero, the REPE prefix does not run the CMPSB instruction, leaving the ZF flag undetermined. [ bp: Add a comment about the len==0 case. ] Fixes: 62bd0337d0c4 ("Top header file for new x86 setup code") Closes: https://sashiko.dev/#/patchset/20260701-pvh-kasan-inline-v6-0-ba99045dfa9f%40igalia.com Suggested-by: Borislav Petkov Signed-off-by: Mauricio Faria de Oliveira Signed-off-by: Borislav Petkov (AMD) Link: https://lore.kernel.org/all/20260721-pvh-kasan-inline-v7-2-38979a50cef0@igalia.com

x86/boot/compressed: Disable jump tables

2026-07-23T08:06:58+00:00

After a recent upstream LLVM change to start generating jump and lookup tables in switch statements in more instances [1], linking the compressed x86 boot image when CONFIG_KERNEL_ZSTD is enabled fails with: ld.lld: error: Unexpected run-time relocations (.rela) detected! Dumping the relocations in misc.o, which is the only file influenced by CONFIG_KERNEL_ZSTD in the decompressor, shows dynamic relocations to some string constants, which correspond to the string literals in the switch statement in handle_zstd_error(): Relocation section '.rela.data.rel.ro' at offset 0x277b0 contains 31 entries: Offset Info Type Symbol's Value Symbol's Name + Addend 0000000000000000 0000006600000001 R_X86_64_64 0000000000000000 .rodata.str1.1 + 73a 0000000000000008 0000006600000001 R_X86_64_64 0000000000000000 .rodata.str1.1 + 78e 0000000000000010 0000006600000001 R_X86_64_64 0000000000000000 .rodata.str1.1 + 78e 0000000000000018 0000006600000001 R_X86_64_64 0000000000000000 .rodata.str1.1 + 78e ... This optimization is problematic for the decompressor environment, as it is built as -fPIE without any explicit absolute references (as described at the top of misc.c) while not applying any dynamic relocations, hence the linker assertion. To opt out of this optimization, which is of little value in this special early boot code, and to mirror the other x86 startup code in arch/x86/boot/startup, disable jump tables in the decompressor. Signed-off-by: Nathan Chancellor Signed-off-by: Ingo Molnar Acked-by: Ard Biesheuvel Cc: Bill Wendling Cc: Justin Stitt Cc: Nick Desaulniers Cc: "H. Peter Anvin" Cc: Peter Zijlstra Cc: stable@vger.kernel.org Link: https://github.com/llvm/llvm-project/commit/fa02a6ed66b1700c996b49c96c6bc0eb014c9518 [1] Link: https://patch.msgid.link/20260722-x86-boot-compressed-disable-jt-clang-v2-1-7373d38482fb@kernel.org Closes: https://github.com/ClangBuiltLinux/linux/issues/2165

x86/boot: Validate console=uart8250 baud rate to fix early boot hang

2026-07-14T09:01:33+00:00

When the baud rate is empty, 0, invalid, or overflows to 0 when stored as an int, the system will hang during early boot because of a division by zero in early_serial_init(). Fall back to DEFAULT_BAUD when the resulting baud rate is 0 to prevent an early system hang. Fixes: ce0aa5dd20e4 ("x86, setup: Make the setup code also accept console=uart8250") Signed-off-by: Thorsten Blum Signed-off-by: Ingo Molnar Cc: "H. Peter Anvin" Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260713194924.126472-3-thorsten.blum@linux.dev

x86/boot: Reject too long acpi_rsdp= values

2026-07-12T02:25:26+00:00

cmdline_find_option() returns the full length of the parsed acpi_rsdp= value. get_cmdline_acpi_rsdp() then silently truncates values which do not fit in the val[] buffer. Prevent boot_kstrtoul() from parsing a truncated value and then the kernel from silently using the wrong RSDP address, see discussion in Link:. Issue a warning so that the user is aware that s/he supplied a malformed value and can get feedback instead of silent crashes. [ bp: Make commit message more precise. ] Fixes: 3c98e71b42a7 ("x86/boot: Add "acpi_rsdp=" early parsing") Signed-off-by: Thorsten Blum Signed-off-by: Borislav Petkov (AMD) Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20260617130417.36651-4-thorsten.blum@linux.dev