[PATCH 0/5] x86/boot: Early boot cleanups

From: Brian Gerst

Date: Thu Jul 23 2026 - 23:03:39 EST


This series moves clearing BSS and copying boot parameters and the
command line to the early boot code. Clearing BSS early prevents using
unitialized data making the code more robust. Copying the boot
parameters early simplifies the code by not needing to pass around the
orignal source pointer and does not need special handling when
encryption is enabled.

Note: The memory encryption parts have only been compile tested due to
lack of access to capable hardware.

Brian Gerst (5):
x86/sme: Clear decrypted BSS separately
x86/boot/64: Clear BSS as early as possible
x86/boot: Remove hardcoded boot_param constants
x86/boot/64: Remove copy_bootdata() call
x86/boot/64: Copy boot parameters and command line earlier

arch/x86/boot/startup/map_kernel.c | 10 ++--
arch/x86/boot/startup/sme.c | 6 ++-
arch/x86/include/asm/mem_encrypt.h | 14 ++----
arch/x86/include/asm/setup.h | 11 ++---
arch/x86/kernel/asm-offsets.c | 3 ++
arch/x86/kernel/head64.c | 61 ++---------------------
arch/x86/kernel/head_32.S | 4 +-
arch/x86/kernel/head_64.S | 47 ++++++++++++++----
arch/x86/kernel/setup.c | 1 +
arch/x86/kernel/smpboot.c | 2 +-
arch/x86/kernel/vmlinux.lds.S | 2 +-
arch/x86/mm/mem_encrypt_amd.c | 64 ++-----------------------
arch/x86/xen/enlighten_pv.c | 4 +-
arch/x86/xen/xen-head.S | 5 +-
drivers/firmware/efi/libstub/x86-stub.c | 6 +--
15 files changed, 76 insertions(+), 164 deletions(-)


base-commit: 1b57632fa6f9ad161c2633a6df4c65e973790218
--
2.55.0