From 44f155b4b07b8293472c9797d5b39839b91041ca Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Fri, 19 Nov 2021 13:47:43 +0200 Subject: efi/libstub: x86/mixed: increase supported argument count Increase the number of arguments supported by mixed mode calls, so that we will be able to call into the TCG2 protocol to measure the initrd and extend the associated PCR. This involves the TCG2 protocol's hash_log_extend_event() method, which takes five arguments, three of which are u64 and need to be split, producing a total of 8 outgoing Signed-off-by: Ard Biesheuvel Signed-off-by: Ilias Apalodimas Link: https://lore.kernel.org/r/20211119114745.1560453-3-ilias.apalodimas@linaro.org Signed-off-by: Ard Biesheuvel --- arch/x86/platform/efi/efi_thunk_64.S | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'arch/x86/platform') diff --git a/arch/x86/platform/efi/efi_thunk_64.S b/arch/x86/platform/efi/efi_thunk_64.S index fd3dd1708eba..5b7c6e09954e 100644 --- a/arch/x86/platform/efi/efi_thunk_64.S +++ b/arch/x86/platform/efi/efi_thunk_64.S @@ -36,6 +36,17 @@ SYM_CODE_START(__efi64_thunk) movq efi_mixed_mode_stack_pa(%rip), %rsp push %rax + /* + * Copy args passed via the stack + */ + subq $0x24, %rsp + movq 0x18(%rax), %rbp + movq 0x20(%rax), %rbx + movq 0x28(%rax), %rax + movl %ebp, 0x18(%rsp) + movl %ebx, 0x1c(%rsp) + movl %eax, 0x20(%rsp) + /* * Calculate the physical address of the kernel text. */ @@ -47,7 +58,6 @@ SYM_CODE_START(__efi64_thunk) subq %rax, %rbp subq %rax, %rbx - subq $28, %rsp movl %ebx, 0x0(%rsp) /* return address */ movl %esi, 0x4(%rsp) movl %edx, 0x8(%rsp) @@ -60,7 +70,7 @@ SYM_CODE_START(__efi64_thunk) pushq %rdi /* EFI runtime service address */ lretq -1: movq 24(%rsp), %rsp +1: movq 0x20(%rsp), %rsp pop %rbx pop %rbp retq -- cgit v1.2.3