[PATCH v6 00/10] x86: Confine early 1:1 mapped startup code

Ard Biesheuvel
2024-02-26T14:30:00Z

This is a resend of v5 [0] with some touchups applied.

Changes since v5:
- drop patches that have been merged
- rebase onto latest tip/x86/boot
- fix comment regarding CR4.PGE wrt flushing of global TLB entries
- avoid adding startup code to .noinstr.text as it triggers objtool
warnings

[0] https://lore.kernel.org/all/20240221113506.2565718-18-ardb+git@google.com/

Cc: Kevin Loughlin <kevinloughlin@google.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Dionna Glaze <dionnaglaze@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>

Ard Biesheuvel (10):
x86/startup_64: Simplify CR4 handling in startup code
x86/startup_64: Defer assignment of 5-level paging global variables
x86/startup_64: Simplify calculation of initial page table address
x86/startup_64: Simplify virtual switch on primary boot
x86/sme: Avoid SME/SVE related checks on non-SME/SVE platforms
efi/libstub: Add generic support for parsing mem_encrypt=
x86/boot: Move mem_encrypt= parsing to the decompressor
x86/sme: Move early SME kernel encryption handling into .head.text
x86/sev: Move early startup code into .head.text section
x86/startup_64: Drop global variables keeping track of LA57 state

arch/x86/boot/compressed/misc.c | 15 ++++
arch/x86/boot/compressed/misc.h | 4 -
arch/x86/boot/compressed/pgtable_64.c | 12 ---
arch/x86/boot/compressed/sev.c | 3 +
arch/x86/boot/compressed/vmlinux.lds.S | 1 +
arch/x86/include/asm/mem_encrypt.h | 8 +-
arch/x86/include/asm/pgtable_64_types.h | 43 ++++-----
arch/x86/include/asm/sev.h | 10 +--
arch/x86/include/uapi/asm/bootparam.h | 1 +
arch/x86/kernel/cpu/common.c | 2 -
arch/x86/kernel/head64.c | 67 +++-----------
arch/x86/kernel/head_64.S | 93 ++++++++------------
arch/x86/kernel/sev-shared.c | 23 +++--
arch/x86/kernel/sev.c | 14 +--
arch/x86/lib/Makefile | 13 ---
arch/x86/mm/kasan_init_64.c | 3 -
arch/x86/mm/mem_encrypt_identity.c | 89 +++++--------------
drivers/firmware/efi/libstub/efi-stub-helper.c | 8 ++
drivers/firmware/efi/libstub/efistub.h | 2 +-
drivers/firmware/efi/libstub/x86-stub.c | 3 +
20 files changed, 152 insertions(+), 262 deletions(-)

--
2.44.0.rc0.258.g7320e95886-goog