diff options
| author | Ard Biesheuvel <ardb@kernel.org> | 2022-11-22 17:10:11 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-03-06 14:45:13 +0000 |
| commit | 2e47116315a08bd5fa451bbeb66cb14ffc3f0de1 (patch) | |
| tree | dd14b34470c75a0dd688e9fe88824ad50546090e | |
| parent | 29134968f72da9337dff949bba0bdb0c5134ba0a (diff) | |
| download | linux-2e47116315a08bd5fa451bbeb66cb14ffc3f0de1.tar.gz | |
x86/boot/compressed: Move startup32_load_idt() into .text section
commit c6355995ba471d7ad574174e593192ce805c7e1a upstream.
Convert startup32_load_idt() into an ordinary function and move it into
the .text section. This involves turning the rva() immediates into ones
derived from a local label, and preserving/restoring the %ebp and %ebx
as per the calling convention.
Also move the #ifdef to the only existing call site. This makes it clear
that the function call does nothing if support for memory encryption is
not compiled in.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20221122161017.2426828-12-ardb@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/x86/boot/compressed/head_64.S | 31 |
1 files changed, 20 insertions, 11 deletions
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index 9d1e1ccab2566e..53f3f01f88af26 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -118,7 +118,9 @@ SYM_FUNC_START(startup_32) 1: /* Setup Exception handling for SEV-ES */ +#ifdef CONFIG_AMD_MEM_ENCRYPT call startup32_load_idt +#endif /* Make sure cpu supports long mode. */ call verify_cpu @@ -732,10 +734,8 @@ SYM_DATA_START(boot32_idt) .quad 0 .endr SYM_DATA_END_LABEL(boot32_idt, SYM_L_GLOBAL, boot32_idt_end) -#endif -#ifdef CONFIG_AMD_MEM_ENCRYPT - __HEAD + .text .code32 /* * Write an IDT entry into boot32_idt @@ -768,24 +768,32 @@ SYM_FUNC_START_LOCAL(startup32_set_idt_entry) RET SYM_FUNC_END(startup32_set_idt_entry) -#endif SYM_FUNC_START(startup32_load_idt) -#ifdef CONFIG_AMD_MEM_ENCRYPT - leal rva(boot32_idt)(%ebp), %ecx + push %ebp + push %ebx + + call 1f +1: pop %ebp + + leal (boot32_idt - 1b)(%ebp), %ebx /* #VC handler */ - leal rva(startup32_vc_handler)(%ebp), %eax + leal (startup32_vc_handler - 1b)(%ebp), %eax movl $X86_TRAP_VC, %edx + movl %ebx, %ecx call startup32_set_idt_entry /* Load IDT */ - leal rva(boot32_idt)(%ebp), %eax - movl %eax, rva(boot32_idt_desc+2)(%ebp) - lidt rva(boot32_idt_desc)(%ebp) -#endif + leal (boot32_idt_desc - 1b)(%ebp), %ecx + movl %ebx, 2(%ecx) + lidt (%ecx) + + pop %ebx + pop %ebp RET SYM_FUNC_END(startup32_load_idt) +#endif /* * Check for the correct C-bit position when the startup_32 boot-path is used. @@ -804,6 +812,7 @@ SYM_FUNC_END(startup32_load_idt) * succeed. An incorrect C-bit position will map all memory unencrypted, so that * the compare will use the encrypted random data and fail. */ + __HEAD SYM_FUNC_START(startup32_check_sev_cbit) #ifdef CONFIG_AMD_MEM_ENCRYPT pushl %eax |