Hi Simon,
On Wed, Aug 10, 2016 at 2:16 AM, Simon Glass sjg@chromium.org wrote:
Hi Bin,
On 9 August 2016 at 00:49, Bin Meng bmeng.cn@gmail.com wrote:
Hi Simon,
On Sun, Aug 7, 2016 at 7:23 AM, Simon Glass sjg@chromium.org wrote:
Bring in these functions from Linux v4.4. They will be needed for EFI loader support.
Signed-off-by: Simon Glass sjg@chromium.org
arch/x86/cpu/Makefile | 2 +- arch/x86/cpu/setjmp.S | 71 +++++++++++++++++++++++++++++++++++++++++++ arch/x86/include/asm/setjmp.h | 24 +++++++++++++++ 3 files changed, 96 insertions(+), 1 deletion(-) create mode 100644 arch/x86/cpu/setjmp.S create mode 100644 arch/x86/include/asm/setjmp.h
diff --git a/arch/x86/cpu/Makefile b/arch/x86/cpu/Makefile index 2667e0b..f5b8c9e 100644 --- a/arch/x86/cpu/Makefile +++ b/arch/x86/cpu/Makefile @@ -10,7 +10,7 @@
extra-y = start.o obj-$(CONFIG_X86_RESET_VECTOR) += resetvec.o start16.o -obj-y += interrupts.o cpu.o cpu_x86.o call64.o +obj-y += interrupts.o cpu.o cpu_x86.o call64.o setjmp.o
AFLAGS_REMOVE_call32.o := -mregparm=3 \ $(if $(CONFIG_EFI_STUB_64BIT),-march=i386 -m32) diff --git a/arch/x86/cpu/setjmp.S b/arch/x86/cpu/setjmp.S new file mode 100644 index 0000000..24e7d8a --- /dev/null +++ b/arch/x86/cpu/setjmp.S @@ -0,0 +1,71 @@ +/*
- Written by H. Peter Anvin hpa@zytor.com
- Brought in from Linux v4.4 and modified for U-Boot
- From Linux arch/um/sys-i386/setjmp.S
- SPDX-License-Identifier: GPL-2.0
- */
+#include <asm/global_data.h> +#include <asm/msr-index.h> +#include <asm/processor-flags.h>
+#define _REGPARM
+/*
- The jmp_buf is assumed to contain the following, in order:
%ebx
%esp
%ebp
%esi
%edi
<return address>- */
/** rdi - 32-bit code segment selector* rsi - target address* rdx - table address (0 if none)*/The comment above looks irrelevant.
OK, will drop.
.text.align 4.globl setjmp.type setjmp, @function+setjmp: +#ifdef _REGPARM
movl %eax,%edxnits: needs space after ",". please fix this globally in this file.
+#else
movl 4(%esp),%edx+#endif
popl %ecx # Return address, and adjust the stackI believe # is deprecated. We should use /* */
OK
xorl %eax,%eax # Return valuemovl %ebx,(%edx)movl %esp,4(%edx) # Post-return %esp!pushl %ecx # Make the call/return stack happymovl %ebp,8(%edx)movl %esi,12(%edx)movl %edi,16(%edx)movl %ecx,20(%edx) # Return addressret.size setjmp,.-setjmpWhat is this .size for?
Size of the function code. It helps with nm --size-sort I think.
.textnits: not necessary
.align 4.globl longjmp.type longjmp, @function+longjmp: +#ifdef _REGPARM
xchgl %eax,%edx+#else
movl 4(%esp),%edx # jmp_ptr addressmovl 8(%esp),%eax # Return value+#endif
movl (%edx),%ebxmovl 4(%edx),%espmovl 8(%edx),%ebpmovl 12(%edx),%esimovl 16(%edx),%edijmp *20(%edx).size longjmp,.-longjmpdiff --git a/arch/x86/include/asm/setjmp.h b/arch/x86/include/asm/setjmp.h new file mode 100644 index 0000000..deef67e --- /dev/null +++ b/arch/x86/include/asm/setjmp.h @@ -0,0 +1,24 @@ +/*
- Written by H. Peter Anvin hpa@zytor.com
- Brought in from Linux v4.4 and modified for U-Boot
- From Linux arch/um/sys-i386/setjmp.S
- SPDX-License-Identifier: GPL-2.0
- */
+#ifndef __setjmp_h +#define __setjmp_h
+struct jmp_buf_data {
unsigned int __ebx;unsigned int __esp;unsigned int __ebp;unsigned int __esi;unsigned int __edi;unsigned int __eip;+};
+int setjmp(struct jmp_buf_data *jmp_buf); +void longjmp(struct jmp_buf_data *jmp_buf);
shouldn't it be void longjmp(struct jmp_buf_data *jmp_buf, int val)? I am wondering how EFI loader could work with this longjmp()?
efi_exit() seems to not need the extra parameter.
This does not look good to me. See efi_start_image(), there is a test against return value of setjmp(), but longjmp() does not provide a return value, which means the return value is undetermined.
if (setjmp(&info->exit_jmp)) { /* We returned from the child image */ return EFI_EXIT(info->exit_status); }
Regards, Bin