diff options
| author | Ard Biesheuvel <ardb@kernel.org> | 2022-11-22 17:10:11 +0100 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2022-11-24 08:57:41 +0100 |
| commit | c6355995ba471d7ad574174e593192ce805c7e1a (patch) | |
| tree | 169ca4498e04573ddd1d0ea37a97b0a3e8c326dc /arch/x86/boot | |
| parent | d73a257f7f86871c3aac24dc20538e3983096647 (diff) | |
x86/boot/compressed: Move startup32_load_idt() into .text section
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
Diffstat (limited to 'arch/x86/boot')
| -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 f9926b3931c2..7aa147f30a0f 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 @@ -716,10 +718,8 @@ 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 @@ -752,24 +752,32 @@ 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. @@ -788,6 +796,7 @@ 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 |